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Definition of catamaran

Illustration of catamaran, examples of catamaran in a sentence.

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'catamaran.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Tamil kaṭṭumaram , from kaṭṭu to tie + maram tree, wood

1673, in the meaning defined above

Dictionary Entries Near catamaran

Cite this entry.

“Catamaran.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/catamaran. Accessed 31 Aug. 2024.

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A Complete Catamaran Guide

• Post Written By: Boater Jer
• Published: January 26, 2020
• Updated: November 27, 2020

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There you are, out on the water when a strange craft approaches.  Is it a sailboat? It sure looks like one until it turns to face you.  That’s when you notice this boat doesn’t have just one hull. It has two hulls and it’s called a catamaran.

Catamarans are unique, and highly stable watercraft.  We’ll explore all the ins and outs of sailing the waters in one of these weird, and awesome multi-hulled craft.  Join me as we explore the wild world of sailing catamarans.

A History Of The Catamaran

It is believed that the first people to use a catamaran design were those living in Australasia.

The succession of boat design in this region was actually very interesting.  The beginning of boats in the area was simple, albeit conventional rafts. These were fashioned from logs strewn together with plant fiber lashings such as those formed using bamboo fiber.  

Catamaran Evolution

The conventional raft gave way to a minimal raft.  This design was basically a conventional raft with two cross beams added in the form of logs.  These would be eventually hollowed out to improve buoyancy.

The next step in the evolution of boats in the Australasian region was the double canoe.  This proved to be the first real catamarans.  

After some time, the form evolved further into the asymmetrical double canoe design.  In this design, one canoe was large and the other attached canoe was smaller.

The asymmetrical design quickly evolved into the single-outrigger boat like the one shown in the photo below.

The final stage of the evolution of the catamaran in the region was to gain a second outrigger.  This in effect created the trimaran with the single central hull and dual outriggers.

Eye Witness Accounts Of Catamarans

In 1697, William Dampier wrote of witnessing a type of seafaring vessel off the coast of Coromandel.  He noted how the locals called the type of boat a catamaran. He also noted that it had multiple hulls (logs) and that they were small vessels that the person operating would have to hang partway into the water, straddling the hull (log).

The name catamaran came from the Tamil.  And yet, it was easily applied by the European visitors to the two hulled sailing vessels that sped across the water in the region.

Although Dampier may have described the catamaran in the 1690s, the type of boat was actually used as early as the 5th century by the Tamil Chola dynasty.  They used boats to move their troops from one island to another. Using this design of boat allowed them to travel heavy, travel quickly and was partially responsible for the conquering of neighboring Burma, Malaysia, and Indonesia.

Building A Boat – Basics Of Catamaran Construction

A boat is usually thought of as being a single-hulled vessel that travels along the surface of the water.  It can have multiple types, shapes, and designs of the hull. However, it is often only thought of as having a single hull.  But, what if it had two hulls? Would that be like taking two separate boats, and making a raft over both of them? In essence, that is exactly what a catamaran is:  two boats made into one.

Advantages Of Multiple Hulls

• More stability than a monohull
• Wide supporting base allows for larger sails than monohull craft of the same length
• Hull does not require the deep-running keel of a standard monohull sailboat
• Less hull drag in the water than a monohull
• Less power required to drive a catamaran forward than a monohull boat

Disadvantages Of Multiple Hulls 

• Due to multiple hulls, construction is more expensive than a monohull design
• Catamaran speed relies on lightweight materials to make a lightweight craft.  This also drives up the cost of construction.
• Extra engineering requirements for multi-hull craft also increase the cost of construction.

Conclusion?  Well, it looks to me like everything about catamarans points towards superiority over monohulls in nearly every way.  But, you get what you pay for. I think the same thing likely applies to cars too. For instance, I have a performance car that cost me about 10k more than the equivalent non-sports car within the same class. 

Yet to drive the vehicle, it performs so much better than the normal version of the car, it really speaks volumes to the difference between a common vehicle, and a performance one.

Speaking of performance vehicles, let’s take a look now at the different kinds and uses of a catamaran.

Catamaran Types

Commercial catamarans – ferries.

One of the most common uses for a catamaran is the commercial use of the vehicle design when it comes to ferries.  This is likely due to the wide, flat deck possibilities of a catamaran versus a monohulled boat. Not only that, but the catamaran is also a much more stable bodied vessel.  This again makes it a superior design for transporting larger land vessels like trucks and so forth. They can easily drive on the ferry without fear of the ferry tipping over.

Some ferries are designed for taking vehicles, like the one you might find in the city of Toronto.  Where it transports cars from the mainland to Toronto Island. Others are designed specifically with the sole purpose of transporting people. I took a look at one such ferry that operates in Germany.  Take a look at the following case study.

Commercial Use Case Study – The Ferry

The FRS Helgoline is a ferry catamaran operating out of Flensburg, Germany, close to the Danish border.

According to the ferry company’s website, the ferry runs using four main engines which are run to a capacity of 12,182 hp combined.  This blasts this ferry at a speed of 35 knots or 65 km/hour. This is equivalent to 40 miles per hour. That’s pretty good considering the size and weight of the ship body this catamaran can carry.

Speaking of capacity, the ship can carry 680 passengers. At 56.4 meters long (185 feet) by 14 meters wide (45.9 feet), that’s a decent passenger capacity. 

Catamaran Passenger Capacity Versus Monohull Boat Passenger Capacity 

The general rule for calculating passenger capacity for a boat is as follows.

Length x Width / 15 = Passenger Capacity

Therefore, the FRS Helgoline should have a calculated capacity calculated as follows.

185 x 45.9 / 15 = 566  

But it actually has a capacity of 680 which is a 20% increase in capacity over a standard monohull.

For comparison, let’s look at a superyacht.  A 48.5m (159 feet) long by 10.7m (35 feet) beam (width of the boat) Palmer Johnson Supersport 48 (valued at about $28.5 million dollars) should have a capacity calculated as follows.

159 x 35 / 15 = 371

In short, 26 feet of difference in length equates to 309 fewer passengers.  It is almost half of the capacity of the catamaran at 26 feet longer length.

Photo courtesy of https://sysyachtsales.com/

Commercial Catamarans – Service Vehicles

Although Catamarans are typically used as ferries due to their stability and ability to carry wide loads on their flat decks, there are many different service catamarans out there as well.  From a support vessel to a crew transfer or search and rescue, catamarans are a solid and stable platform to build a ship on.

This is the Ardea which is a 20 meter (65.6 feet) catamaran to be used for crew transport and as a support ship.  This ship was built by the Echo Marine Group and delivered to Western Australia in early 2019. This particular vessel is in the service of the Cape Preston Sino Iron Project.  

Catamarans are used all around the world, for a variety of tasks, not just ferries or support craft.

Commercial Catamarans – Cruise Lines

Now these are the catamarans we all want to be aboard, aren’t they?  Due to the wide stance, these ships can feature massive halls and wide-open interior areas.  These ships are stable, and some would say even more stable and safer than monohull design ships.  

There are many cruise ship catamarans in use today around the world.  Some of the more ‘famous’ catamaran cruises are those which investigate the Galapagos Islands.  There are several high-end, small fleet, cruise lines operating to the Galapagos which utilize catamaran design vessels as their primary ship type. 

These ships can be extremely comfortable and stable and often offer some reprieve to those who may otherwise feel seasick. It won’t stop the feeling, but the more stable the hull, the less the boat rocks around.

Military Catamarans

Catamarans make excellent military transport vessels.  They are stable and the potential to have a large, flat and wide deck for transporting land craft, troops or acting as a landing pad for vertical take-off aerial craft.  The stability of the two hulls makes the vessel an excellent candidate for military use, and thus it is used for said purpose.

As you can clearly see in the image of the USNS Spearhead, the rear of the vessel has a moveable ramp that can be used for loading and unloading land vehicles.  The interior bay of the craft is visible in the image as well, a large area for storage of vehicles, supplies and more. The crane arm on the back of the ship also shows how it is a versatile craft, set up to act as an excellent support craft with a helicopter landing pad and ample storage and freight capacity.

Recreational Catamarans

Catamaran Personal WatercraftThe wind is in your hair, the warm spray from the hull cutting over the edge of each wave as you skip over the water.  That is life, let me tell you. Personal watercraft have come a long way over the years and the small one, two, three and four-person catamarans have come a long way as well. 

Depending on the options, you can get a small one or two-person catamaran for as little as $1500 new.  That might be an inflatable though. There are some very nice, rigid hull designed catamarans for 1-4 people that range from $3500 to $15000.  And these are basically open, personal watercraft like that shown in the image below.

Using a small catamaran can be quite challenging to learn at first.  Sailing is not for the faint of heart. It requires skill, technique, knowledge of the wind and sea, and a bit of hard work.  But it can be fun, rewarding and a great way to catch some sun and fresh air out on the water. It’s a relatively GREEN sport as well.   Given the use of sails over gas-powered motors that is.

‘Sailing Cats’ – Sailing Catamarans – Yacht & Luxury Class

Here’s where we get into the dreamy boats of the rich and famous.  I priced out a small 43’ luxury Leopard 40 sailing catamaran. Even before I added any extras at all, the base price was $399,000 USD.  I imagine if I added a few of the multiple extras available, and some tax, freight and that sort of thing, I’m easily in half a million dollars.  And that’s the smallest base model.

There are all kinds of luxury catamaran shipbuilders across the world.  From Asia to Europe and The Americas, it seems any major boating country has at least one company building luxury catamarans.  It’s weird that you don’t see more of them on the water though, don’t you think?

Being sailing vessels, these luxury cats require some training in sailing before you get behind the wheel.  And considering the price point, I would definitely want to be at least a semi-decent sailor with some good few years experience under my belt before I would comfortable at the helm of a half-million-dollar sailing cat.  It’s all relative I suppose. I imagine a billionaire might bat an eye at the prospect of wrecking a half-million-dollar boat. But to me, and most of you reading this, that’s likely a lot of money.

‘Power Cats’ – Powered Catamarans

The powered catamaran is one of my favorite boats.  They have sort of a muscle car appearance with the wide and often tall front end of the boats.  I find it to be reminiscent of a large air intake on the front hood of a rally race car like the Subaru WRX, for instance.  These boats are fast, they are stable and handle very well. Catamarans are often considered the boat of choice for long sea voyages due to their stability.  

A powered catamaran will definitely cost more than a powered monohull boat of the same length.  Why? Well, the powered catamaran has one crucial downside. That is, it needs two engines. One for each of the two hulls.  Otherwise, it’s off balance for propulsion. These two engines or motors have to be in sync with each other or again, the propulsion will be off-balance.  Because they have two motors, they have double the maintenance when it comes to maintaining the propulsion system.

More components also means a greater chance of things breaking down.  In essence, it doubles the chances of the ship having a motor break down. The saving grace is that should one motor break, they have a backup, even if it does mean very unbalanced propulsion.  In contrast, a monohull vessel of the same length may only have half the chance of motor failure due to only having one motor, but if that one motor breaks, then what? Call for help, that’s what.  A cat would have a struggling chance to get itself back to port. A monohull would be dead in the water unless it was carrying spare parts or another motor onboard somewhere.

Catamaran Frequently Asked Questions

What is a catamaran cruise.

A catamaran cruise is simply a cruise on a dual hull design boat.  Often used for river cruises, the catamaran which is used as cruise ships are often considerably smaller than their giant monohulled counterparts.

What is the purpose of a catamaran?

A catamaran is a design for a boat that utilizes two hulls.  Due to the flat, platform-like-potential for the deck of the boat, the catamaran is often purposed with transporting materials, vehicles, and people.  For instance, catamarans are quite often used as ferries.

Is catamaran safe?

Catamaran are very safe water craft.   The design of riding on two hulls separated by a gap in between, in essence is like giving a car a double-wide wheel base.  The wider the stance, the more stable the craft, from side to side anyway. And if the length of the boat is proportional to the width, then it becomes an extremely stable craft.  That is why catamarans are often considered the best to be used for long voyages. Yes, catamaran are safe.

What is the difference between a catamaran and a sailboat?

A traditional sailboat is a deep, monohull vessel that has at least one mast extending high into the air above the deck to hold sails.  A catamaran refers to the design of a dual-hull boat and really has nothing to do with sails. Although, catamaran do make excellent sailing boats as well, they are quite capable of acting as power boats and do not require sails if they have the correct amount of powered motors to propel them.  Sailboats, although also able to be powered if a motor is provided, are traditionally monohull and wind-powered exclusively.

Do catamarans have small interiors?

The size of an interior cabin on a boat is typically proportional to the size of the boat itself.  If a catamaran has above-deck cabins, they will likely be able to be of a larger design than those you would find on deck of a monohull boat.  This is because a catamaran has a much wider footprint than a monohull boat of the same length. This extra width would allow for larger on deck cabins.  

How much does a catamaran cost?

A personal watercraft (1-2 person) inflatable catamaran will run you anywhere from $1500-$12000 USD, depending on the quality and features.  The rigid hull catamarans of the same size start at about $4500 USD.

A small cabin cruiser type of catamaran will typically start at about $60000 for a small base model and the price just goes up and up depending on size and features.

For Instance, a 40’, 3 cabin with 1 washroom cat will cost you about $500,000 USD for the base model.  They are considerably more expensive that a monohull of the same length. However, the trade-off is greater stability and a smoother, more comfortable ride.

Is a catamaran more work to maintain?

Technically yes.  Due to having two hulls and if powered, two motors and likely also water jets, this means you have double the oil changes of a boat that would have a single motor.  Once you get past the basic engine and hull maintenance, a catamaran is not that much more work than a monohull ship of the same length.  

The trouble with catamarans in terms of maintenance, is that once they reach a certain length, the width becomes more than a standard lane on the road.  That being said, if you ever need to transport the boat via land, it can be quite the challenge. Especially if you need to pay to have a police escort for an extra-wide trailer.  And special licensing might be involved as well.

What is the difference between a catamaran and a trimaran?

A catamaran is a dual hull boat.  In other words, it has two hulls. A trimaran has three hulls.  

Is a catamaran considered a yacht?

According to Oxford dictionary, a yacht is a medium-sized sailboat equipped for cruising or racing.  A catamaran, on the other hand, is a boat with two hulls. Therefore, a catamaran can most certainly also be a yacht.  And likewise, if a yacht has two hulls, then it is a catamaran as well.

Can you get seasick on a catamaran?

Seasickness occurs when a person feels nauseous from the swaying motion of a rocking ship.  These feelings may be lessened on a catamaran, due to their extra stability. However, a catamaran may be slightly more stable than a monohull of the same length, but it is still a boat.  And it will still make someone who experiences seasickness continue to feel the ill effects.

Are catamarans more stable in rough seas?

Catamarans are known to be more stable than monohull ships of the same length.  This is why catamarans are often the ship type of choice for long sea voyages due to their stability.

Why do catamarans capsize?

Catamarans are not known for capsizing.  The larger vessels that is anyway. But, it does happen from time to time.  Catamarans are known for their stability, so typically if a capsize event should occur, it is typical for them to be extreme circumstances.  

Personal watercraft catamarans are a different story though.  These are in fact known for tipping over. Not because they are less stable than their monohull counterparts of the same length.  But instead, because they are able to go considerably faster than monohull personal watercraft of the same length (not including powered craft though).  This is due to the sailing cats being able to have a larger sail than a small monohull sailboat of the same length.

Due to the extra sail, they are able to travel faster than monohull sailboats of the same length.  This allows them to whip around on the water and at higher speeds, whipping your cat about quick can easily send it over sideways. Extra speed means fast turns carry momentum in the direction of travel and that extra speed equates to tipping over if turned too fast.  To sum up, they capsize due to user error or extreme events.

Which is safer, a catamaran or a monohull?

Due to the extra stability of having a wider footprint than a monohull, a catamaran of the same length is the safer vessel.

Are catamarans safer than sailboats?

The same rule applies to stability versus the length of the hull.  A cat will always be the more stable length for length. However, due to their ability to go much faster than a monohull sailboat, this kind of cancels out some of the added safety due to stability.  With that in mind, they may just be about the same but there is one generalization we can make when comparing the safety of catamarans vs sailboats: At the same speed, and of equal length, sailing or power catamaran will be safer than a monohull sailboat.

How fast can catamarans go?

The speed a catamaran can go is entirely dependent upon the hull design, weight of the vessel, the strength of propulsion (be it wind or powered) and so on.  The general rule is that in terms of sailing cats vs monohull sailboats, a cat of equal length can typically go faster than a sailboat.  

In terms of powered cats vs powerboats, a powered catamaran will typically require less energy to move forward than a monohull of the same sort of hull design (but monohull of course) and thus a cat should, in theory, be able to go faster than a monohull when both are using propulsion that is equal in power.

Bibliography

• Wikipedia – Catamarans
• Mahdi, Waruno (1999). “The Dispersal of Austronesian boat forms in the Indian Ocean”. In Blench, Roger; Spriggs, Matthew (eds.). Archaeology and Language III: Artefacts languages, and texts . One World Archaeology. 34 . Routledge. pp. 144–179. ISBN 0415100542 .
• Wikipedia – Spearhead -class expeditionary fast transport
• https://www.tiki-toki.com/timeline/entry/169516/Origin-of-the-catamaran/#vars!panel=1620923!
• https://www.austal.com/ships/passenger-express-56
• https://www.adventure-life.com/galapagos/galapagos-catamaran-cruises

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What Is a Catamaran?

If you’re thinking of chartering a catamaran on your next trip, read through our guide and get up to speed on two hulled yachts! We offer Catamarans for charter in over 60 countries and the entire selection can be seen on our Catamaran charter page.

A Catamaran is a sail or engine-powered boat with a double hull, a distinct feature that makes it immediately recognizable once you're aware of the design. People often question whether a catamaran is a yacht, and due to the sleek style, versatility, speed capabilities, and comfort, a catamaran definitely earns the yacht stamp of approval. Due to these same characteristics, catamarans are becoming an increasingly popular choice among avid leisure and sport sailors.

The elegant and unique catamaran style isn't a new development - it's actually a centuries-old design that's been modified and built upon to become what it is today.

The first Catamaran was created in India, borrowing its modern name from the original Tamil word kattumaram, meaning "logs bound together". The first design was simply a raft made of tree trunks, built in the fishing communities of Tamil Nadu in southern India and used to invade several Southeast Asian countries as early as the 5th century. The kattumaram quickly became the favoured vessel style throughout Polynesia and Micronesia.

Evolved by American Nathanael Herreshoff in the 1870s and further developed in the 1950s, the catamaran concept really took off in the 20th century. It was soon functioning as a full-fledged yacht, able to compete in the racing arena with mono-hulled boats without compromising luxury. Nowadays, catamarans attract both sport and leisure boaters with its versatility, speed, and comfort.

What are the Characteristics of a Catamaran Hull?

The most obvious characteristic of a catamaran is the twin hull, but there are more benefits to the cleverly crafted underside. When compared to a monohull yacht of the same size, the catamaran hull has several big advantages. Catamaran hulls are noted for having less volume, lighter displacement, and shallower draft (ie less of the boat is below water) when compared to monohull vessels. The shallow draft is especially appealing, allowing for use in shallow water and giving the captain the option to pull the boat right up to shore without worry.

Additionally, because of the hull design, catamarans boast a smaller hydrodynamic resistance, ultimately making them more economic since they don't need as much fuel to propel them forward. And for those sailors still strengthening their sea legs, the double hull increases the catamaran's overall balance and stability by reducing the amount of wave-induced motion. So long seasickness!

Catamarans have a lot of space. The living area in between the two hulls offers a dining and lounging area as well as a spacious kitchen. You also find outside lounging areas at the back and in the front of the yacht. The various places to relax mean a lot of privacy on board. The two hulls further increase the privacy aspect because the cabins are separated by the central living area and each hull has their separate entrance in most cases. This makes the Catamaran the ideal yacht to charter for two couples, two families, a group of friends or a large family. The cabins in the hulls are spacious and comfortable and their sizes vary with the exact Catamaran model.

So in summary, catamarans:

• have two hulls, usually connected by a bridgedeck
• can be sailed in shallow water
• use less fuel, because they have low hydrodynamic resistance
• tend to be very stable
• have a lot of space for dining and lounging and preparing food
• offer greater privacy than monohull yachts

To give you an idea of the space and amenities on board a Catamaran, do have a look at the many pictures of our Fountain Pajot Alegria 67 for charter in the British Virgin Islands .

How to Sail a Catamaran

You're sold on the idea of a catamaran, but now comes the question, how hard is it to sail a catamaran? Learning how to sail a catamaran is relatively straight forward if you're already trained in the basics of sailing. Although it does differ from monohull vessels, the idea is the same. Be prepared to tweak your sail trimming skills and get used to the difference in motion (or lack thereof) with the catamaran.

The catamaran is gaining popularity because the better-balanced hull and twin engines make it arguably easier to operate than a monohull yacht. Fluid maneuverability means that even one person can sail a catamaran as long as they've built up enough sail experience. Still, it's never a bad idea to get some formal training; the ASA and RYA both offer catamaran sailing courses to help enhance your skills.

How Fast Can a Catamaran Sail?

Catamaran's can cruise! Their speed is just another reason why the boat has become so sought-after in recent years. A sailing catamaran can typically perform 25% - 30% faster than a monohull of the same size.

So just how fast can they go? Cats average about 10 knots with top speeds reaching around 15 knots. Just keep your weight in mind - catamarans respond sensitively to heavy loads and will perform slower if overweight.

Why Charter a Catamaran?

When compared to a monohull boat of the same size, a catamaran has a tendency to be a bit more expensive to charter. However, your trip itinerary might require certain criteria that make spending a bit more worth it. For example, the flat plane and stability of a catamaran are ideally suited for a family to enjoy their holidays in a lot of comfort. It is also ideal for a scuba diving holiday , allowing divers to gear up and enter/exit the water with ease. Additionally, big parties usually find catamarans better suited for their needs in terms of deck space and overall comfort.

A Catamaran is the ideal yacht for a relaxing vacation as it boasts a lot of space, stability and living spaces - it truly is your floating hotel. But note that a catamaran holiday does not need to break the bank and is very affordable in comparison to a vacation in a hotel or a villa depending on the type and size of a catamaran you decide to go for. 

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Catamarans are a fun alternative to the traditional sailing yacht and the value for money is unrivalled for a yacht holiay. They provide comfort, flexibility and a lot of space to spend your time on the sea. You can also check out this Comprehensive guide to chartering a yacht for more information.

Curious? Check out Boataffair's huge choice of catamarans to charter in the world's most sought after destinations.

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Catamarans: A Complete Guide to Multihull Boats

Catamarans have been a part of sailing history for centuries and continue to be popular for their stability, spaciousness, and performance. Developed by various cultures around the world, the principles of catamaran design have evolved over time to become optimized for both pleasure cruising and racing. This complete guide will help you understand the essentials of catamarans, their unique characteristics, and how to choose the right one for your needs.

From the basic concepts of multihull design, performance, and handling, we will explore the advantages and benefits of a catamaran in terms of safety and comfort on board.

Along the way, we will discuss maintenance considerations, distinctive catamaran brands and models, and how a catamaran lifestyle can compare to more traditional sailing options .

Finally, we will provide learning resources and frequently asked questions tailored to both seasoned sailors and newcomers to the world of catamarans.

Key Takeaways

• Catamarans are known for their stability, spaciousness, and performance
• This guide covers aspects like design, handling, safety, and choosing the right catamaran
• Resources and frequently asked questions provide additional insights for potential catamaran owners

Understanding Catamarans

Design Characteristics

Catamarans are known for their unique design, which features two parallel hulls connected by a deck. This design provides several advantages over traditional monohull boats, such as stability and speed.

With their wide beam, catamarans have a reduced risk of capsizing and can access shallow waters due to their shallow drafts 1 .

One of the notable aspects of a catamaran is its twin hulls, which offer increased living space and comfort compared to a monohull. Additionally, catamarans are often favored by recreational and competitive sailors for their excellent maneuverability 2 .

The materials used for constructing catamarans range from wood to fiberglass, and even aluminum for high-performance vessels. Aluminum catamarans are known for their strength, lightweight structure, and resistance to corrosion 3 .

Hulls and Construction

The hulls in a catamaran are crucial to its stability and performance. These hulls help distribute the weight evenly across the water surface, minimizing drag and allowing for smoother sailing.

In general, the hulls can be categorized into two types:

• Symmetrical Hulls : The hull shape is similar on both sides, which enhances balance and stability in various sailing conditions.
• Asymmetrical Hulls : One side of the hull is designed differently than the other, which can be advantageous when sailing upwind.

The construction materials used in building catamaran hulls also play a vital role in the boat's performance and durability. Common materials include:

• Fiberglass : A popular choice due to its lightweight, strength, and ease of maintenance.
• Wood : Traditional material that offers a classic look, but requires more maintenance than fiberglass or aluminum.
• Aluminum : Lightweight and strong, aluminum is an excellent choice for high-performance catamarans 4 .

Multihulls vs Monohulls

There's often a debate between the benefits of multihull boats, such as catamarans or trimarans, and monohull boats. Here are some key differences between the two:

• Stability : Due to their wide beam and reduced heeling, catamarans offer improved stability compared to monohulls. This makes them an attractive option for those who want to avoid seasickness or feel more comfortable on the water 5 .
• Speed : Multihull boats are known for their speed, which results from their ability to minimize drag and maintain a level sail.
• Living Space : Catamarans and other multihulls generally have more living space, as both the hulls and the connecting deck can be utilized for accommodation and storage.
• Maneuverability : While monohulls are known for their agility and ability to point close to the wind, catamarans can still offer exceptional maneuverability when properly sailed 6 .

Performance and Handling

Speed and Efficiency

Power catamarans have gained popularity for offering a unique combination of speed, efficiency, and stability. Their dual-hull design allows for less water resistance, which directly translates to higher speeds and better fuel efficiency compared to traditional monohull boats.

In addition, the wide beam provided by the two hulls ensures a stable ride even at higher speeds. This makes power catamarans ideal for cruising, fishing, and watersports ( Boating Beast ).

Sailing Dynamics

When it comes to sailing catamarans , the performance is affected by factors such as keel, rudders, mast, and sails.

Their wide beam and dual-hull design provide inherent stability and reduced heeling effect, making them less likely to capsize compared to monohulls.

I should also note that catamarans have a shallow draft, which gives them the ability to access shallow waters that may be off-limits to other boats ( Navigating the Waters ).

In my experience, the lighter weight of a catamaran and its aerodynamic design can contribute to remarkable sailing performance under different wind conditions.

The larger sail area relative to hull weight allows them to harness more wind power, further enhancing their speed and agility on the water.

Maneuvering and Docking

Maneuvering and docking a power catamaran involves understanding its unique handling characteristics.

The presence of two engines in separate hulls allows for more precise control in confined spaces such as marinas.

The maneuverability of these boats is typically improved by the use of dual rudders that are located close to each powered hull for efficient steering ( BoatUS ).

When docking under power, I find it helpful to carefully assess the wind and current conditions beforehand.

This is because catamarans can be more sensitive to windage due to their larger surface area above the waterline.

By understanding how these forces may affect the boat, I can make adjustments to my approach and successfully dock the catamaran without any incidents.

Safety and Comfort on Board

Safety Features

Safety is a top priority when sailing any type of vessel, including catamarans. A well-built catamaran offers several features aimed at ensuring the safety of those onboard.

First, catamarans have inherent stability due to their wide beam and twin hull design . This makes them less prone to capsizing than monohull boats. This stability allows me to confidently navigate various water conditions .

In addition to stability, catamarans are designed with positive buoyancy, making them almost unsinkable . Of course, safety equipment such as lifejackets, flares, and first aid kits should always be onboard and well-maintained.

Furthermore, you should also stay updated on weather conditions, avoid sailing in high-risk areas, and learn your boat's safe sail limits.

Living Spaces and Comfort

When it comes to living spaces, I value comfort and practicality as essential features for my time on the water. Catamarans offer a unique advantage in this regard, as their dual hulls create spacious living areas.

Most catamarans are designed with separate cabins in each hull, allowing for privacy and comfort when sleeping. Additionally, these boats typically feature shallow drafts , which means I can access shallow waters and anchor close to shore.

The main living area, or salon, is situated on the bridge deck between the hulls. It usually includes a seating area, a dining table, and a galley (kitchen). Large windows provide ample natural light and panoramic views, making the space feel open and bright. Some catamarans even have the option for an additional living area on the upper deck where you can enjoy the sun and breeze.

One aspect of catamaran living I truly appreciate is the ample storage available. Each cabin typically has built-in storage spaces for clothes, gear, and personal items. There are also designated areas for equipment such as spare sails, tools, and water toys. This makes it easy for me to keep my belongings organized and make the most of my time on the water.

Maintaining a Catamaran

Routine Maintenance

In order to keep my catamaran in the best possible shape, I make sure to perform routine maintenance tasks. These tasks are essential to extend the life of the components and ensure smooth sailing:

• Cleaning : Regularly cleaning the deck, hulls, and sails prevents buildup of dirt, algae, and other debris that could affect performance.
• Inspection : Periodically inspecting my catamaran allows me to detect any potential issues before they become significant problems. I pay close attention to the rigging, sails, and lines on my boat.
• Lubrication : Keeping all moving parts lubricated is vital to prevent friction and wear on components such as winches and pulleys.
• Antifouling : Applying antifouling paint to the hulls of my catamaran helps prevent the growth of marine organisms that can damage the boat and reduce its speed. Make sure to do this at least once a year.

Dealing with Wear and Tear

Despite my best efforts to keep my catamaran well-maintained, wear and tear is inevitable. Here's how I deal with common issues that could arise from regular use:

• Repairs : When I notice signs of wear on sails, lines, or rigging components, I make it a priority to repair or replace them promptly. Neglecting these issues can lead to more significant problems and affect the boat's performance.
• Hull maintenance : If I find dents, scratches, or stiff rudders on my catamaran's hulls, I address them immediately. Repairing any damage not only ensures smooth sailing but also prevents further issues from developing.
• Sail care : Over time, my sails can become stretched, torn, or damaged due to exposure to sun, wind, and saltwater. Regularly inspecting them for signs of wear and making any necessary repairs or replacements helps maintain optimal performance.
• Rust and corrosion prevention : Since my catamaran is made of various metal components, I need to protect them from rust and corrosion. I routinely check for signs of corrosion and apply anti-corrosive treatments when needed.

Catamaran Brands and Models

High-Performance Models

In recent years, there has been a growing interest in high-performance catamarans. I have seen a variety of brands and models that have impressed me with their performance capabilities. One notable brand is Fountaine Pajot , which has a long history of producing a range of sailing catamarans and power catamarans. Some of their popular models include the Tanna 47 and the Bali 4.4 .

Another high-performance catamaran I've come across is the Leopard 40 . Known for their speed and exceptional handling in various conditions, the Leopard brand started with sailing catamarans and has since expanded to include power catamarans. Their models range from 40 to 53 feet long, offering both power and luxury for those looking for a thrilling experience on the water.

Cruising Catamarans

When it comes to cruising catamarans, the Lagoon brand is synonymous with luxury and comfort. With a range of sailing catamarans from 40 to 70 feet long, Lagoon offers spacious catamarans for extended bluewater cruising. Their 60- and 70-foot power catamarans are equally impressive, providing ample living space and smooth sailing experiences.

I've also found the Aquila 42 PC to be a remarkable cruising catamaran. With a focus on design and innovation, Aquila has produced catamarans perfect for exploring the open sea with friends and family. Their spacious, stable designs allow for a more enjoyable and serene journey, ensuring you arrive at your destination comfortably.

The Catamaran Lifestyle

Anchoring and Cruising

I find catamarans to be a fantastic choice for cruising and anchoring , which is a critical part of living the catamaran lifestyle . Catamarans have several advantages when it comes to anchoring and cruising, such as:

• Stability : Due to their wide beam and twin hulls, catamarans remain stable during anchoring, which reduces the risk of seasickness.
• Shallow draft : Thanks to their shallow draft , catamarans can anchor close to shore, enabling better access to protected coves and more beautiful beaches.
• Speed : Despite their large size for cruising vessels , catamarans are generally faster than monohulls. This is a result of their slim hulls and reduced water resistance.

When it comes to anchoring, catamarans can make use of their shallow draft to anchor in locations that other boats cannot. This allows for a greater range of cruising spots, which makes the overall experience much more enjoyable and unique.

Living on a Catamaran Full-time

For many catamaran enthusiasts, the dream of living full-time on a catamaran is entirely possible. While not without challenges, there are several factors that make living aboard a catamaran an enjoyable experience:

• Spacious living areas : Catamarans generally have more living area compared to monohulls, providing ample space for the whole crew.
• Privacy : The separate hulls allow for private cabins, ensuring that everyone on board has their space.
• Stability : As mentioned earlier, catamarans are stable vessels, making living on them more comfortable than monohulls.

Choosing Your Catamaran

Comparing Models and Features

When I start to look for the perfect catamaran, the first thing I focus on is comparing various models and features .

I determine the key factors that are essential for my needs, such as size, passenger comfort, and performance. By doing so, I can identify which catamaran models are most suitable for me.

For example, if I plan to sail with a large group, I would look for a catamaran that offers ample space both inside and out.

To help me with my comparisons, I usually create a table or list of the different models and their features:

This visual aid makes it easier for me to sort the options and prioritize my considerations, such as price, yacht type, and brand.

New vs. Second-Hand

Another critical aspect of choosing a catamaran is deciding between a new or second-hand boat.

Both options have their pros and cons, and ultimately it depends on my preferences and budget.

If I can afford a new catamaran, I get the advantage of the latest design , features, and technology. Plus, I typically receive better warranty coverage and support from the manufacturer.

However, new catamarans are more expensive and can have long wait times due to high demand.

On the other hand, purchasing a second-hand catamaran can save me a significant amount of money, and I might find a high-quality boat with low mileage or well-maintained by the previous owner.

However, this option carries more risks, as I need to be knowledgeable about potential maintenance issues and conduct a thorough inspection before purchase.

Learning Resources

Books and Manuals

When it comes to learning about catamarans, there are plenty of books and manuals available.

One of the highly recommended books is Multihull Voyaging by Thomas Firth Jones. This book provides a comprehensive understanding of multihulls, including catamarans, and is an essential guide for any beginner sailor.

Another great book to check out is Catamarans: The Complete Guide for Cruising Sailors by Gregor Tarjan.

With a foreword by Charles K. Chiodi, publisher of Multihulls Magazine, this book covers all aspects of cruising catamarans. It includes detailed information on design, construction, and maintenance, as well as tips and tricks for sailing a catamaran.

Here are a few more books that I find valuable:

• The Catamaran Book by Tim Bartlett, an excellent resource for both beginners and experienced sailors
• Catamaran Sailing: From Start to Finish by Phil Berman and Lenny Rudow, a comprehensive guide to both catamaran racing and cruising

Online Content and Photography

In addition to books, you can find plenty of online content and photography about catamarans.

Websites like Sailaway Blog and Boating Guide offer tips, techniques, and how-to articles for sailing catamarans.

Many of these sites also include stunning photography, showcasing these beautiful vessels in action.

For those who prefer Kindle or e-books, many of these resources are available in digital format.

This makes it easier for you to access them anytime, anywhere, allowing you to keep learning and improving your catamaran sailing skills.

To further enhance your knowledge, you can also join online forums and communities dedicated to catamarans.

These platforms provide invaluable advice and first-hand experiences shared by fellow sailors, as well as recommendations for additional learning resources.

Frequently Asked Questions

What factors should be considered when choosing a catamaran for full-time living?

When choosing a catamaran for full-time living, consider its space and layout , as it will become your home.

Look for a design with a comfortable living area , ample storage, and sufficient berths for the number of people living aboard.

Also, consider fuel efficiency , ease of maintenance, and the catamaran's cruising range .

Lastly, the overall cost of ownership , including insurance and mooring fees, should be considered.

How do catamarans perform in rough sea conditions?

In general, catamarans are known for their stability, which is primarily due to their wide beams. This makes them less prone to capsizing when compared to monohulls.

However, their performance in rough sea conditions will depend on the specific model and design of the catamaran. Some may perform better in certain conditions than others, so researching and selecting the right design is essential.

What are the key differences between sailing a catamaran and a monohull?

One of the main differences between catamarans and monohulls is stability.

Catamarans have a wider beam , which makes them more stable and minimizes the risk of capsizing.

They also have shallower drafts, which allow them to access more shallow waters compared to monohulls.

Additionally, catamarans often have larger living spaces, making them more comfortable and suitable for cruising and full-time living.

What are the advantages of catamarans for long-distance cruising?

Catamarans offer several advantages for long-distance cruising.

Their wide, stable design provides a comfortable ride and reduces the risk of seasickness.

They can also attain higher speeds due to their reduced drag and generally sail faster than monohulls on certain points of sail.

The shallow draft allows them to explore more coastal areas and anchor closer to shore. Lastly, their spacious interiors make them ideal for extended cruises and living aboard.

How does one assess the value of a used catamaran on the market?

Assessing the value of a used catamaran requires thorough research and inspection.

Start by comparing the age, model, and condition of the catamaran to similar listings on the market.

Take note of any upgrades or additions made to the boat, as these can affect the price.

It's essential to inspect the boat in person or hire a professional surveyor to ensure there are no hidden issues that could affect its value.

What essential features should be looked for in a catamaran intended for ocean voyages?

For ocean voyages, look for a catamaran with a strong, well-built hull designed to handle rough conditions.

Safety features such as liferafts, adequate flotation, and sturdy deck hardware are crucial.

A reliable engine and well-maintained rigging and sails are also essential.

In terms of living space, opt for a catamaran with a comfortable, spacious interior and ample storage.

Last but not least, good navigation and communication systems are necessary for long-distance ocean voyages.

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What Is A Catamaran? Does It Have Engines Or Can It Only Sail?

Catamarans are a type of boat that has two hulls connected by a platform. They offer many advantages over traditional monohull boats, including increased stability and improved speed. This article will explore what exactly catamarans are and how they can be powered. We’ll also look at the differences between sailing and motor-powered catamarans to help you decide which one is right for you.

What Is A Catamaran?

A catamaran is a type of boat with two hulls connected by beams. It is usually powered by sails, although all modern catamarans come with inboard motors for propulsion. Catamarans are traditionally used for sailing, fishing, and leisure activities . They can be used in both fresh and salt water, and their light weight allows them to travel at high speeds without using much fuel.

Catamarans are known for their stability and durability due to their wide beam and shallow draft. This makes them ideal for traversing shallow waters or areas where the sea is choppy and unpredictable. They also have the advantage of being able to turn quickly and maneuver easily in tight spaces. Additionally, they provide a smooth ride despite rough seas since the two hulls help to reduce wave impact on the boat itself.

Advantages Of Catamarans

Catamarans offer many advantages to sailors and other seafaring travelers. The primary benefit of catamarans is their stability, due to the fact that they have two hulls that are connected by a platform. This design makes them much more resistant to waves than monohull vessels, which makes them ideal for activities such as fishing or leisurely cruises near shore. Catamarans also tend to be lighter, faster and more fuel efficient than monohulls, making them an attractive choice for sportier outings such as racing or overnight trips. In addition, catamarans can either be powered by engines or sails, giving you the flexibility to choose whatever type of propulsion suits your needs best.

Types Of Catamarans

Catamarans come in a variety of shapes and sizes, from luxurious yachts to fast-moving racing boats. They offer a unique sailing experience, with their twin hulls providing stability and comfort while still able to reach high speeds. Catamarans can be powered by engines or sail, enabling them to move swiftly through the water. Some are designed for serious racing, while others are equipped for leisurely cruising on the open waters. With so many options available, there is sure to be a catamaran that will fit any sailor’s needs. Whether it’s speed or comfort that you’re after, a catamaran can provide an unforgettable experience on the seas.

Sailing Vs. Motor-Powered Catamarans

Catamarans offer many advantages over monohulls and have become a popular choice for many reasons.. They are lightweight, stable, and provide ample space onboard. However, there is one major decision to make when purchasing a catamaran: whether to choose a sailing or motor-powered version.

Sailing catamarans have the traditional look of a boat with two hulls and tall sails, while motor-powered catamarans come equipped with engines and resemble more of a powerboat. Both types of catamarans offer their own unique benefits and drawbacks. Sailing versions are cheaper to purchase but require the sailor to be knowledgeable in sailing tactics in order to navigate easily. Motor-powered versions are more expensive but can be easier to operate in certain conditions due to their greater speed and maneuverability. In the end, it comes down to personal preference as both types can provide an enjoyable experience on the water.

Benefits Of Chartering A Catamaran

Catamarans are a type of sailing vessel with two hulls that are connected with a frame. They are typically very stable and have plenty of deck space for passengers and amenities. Catamarans also come equipped with two engines, so they can travel in calm waters even when there’s no wind to power the sails. The engine also allows them to get back quickly against strong winds or tides, making them great for long trips and passages.

The major benefit of chartering a catamaran is the amount of space it provides compared to traditional monohulls (a boat with one hull). This makes them ideal for larger groups, as they can accommodate more people without feeling cramped. Additionally, catamarans offer great stability in the water – even in choppy conditions – allowing you to feel safe and secure while onboard. Plus, since they don’t require as much maintenance as other boats, they’re perfect for longer periods of time on the water. All these factors make catamarans a great choice for any travel vacation with friends and family.

Frequently Asked Questions

Are catamarans suitable for excursions.

Catamarans are a popular choice for those looking to charter one for an excursion due to their spaciousness and stability. They provide more than enough room for comfortable traveling as well as plenty of storage space, making them an ideal option for extended cruising. Additionally, all catamarans are equipped with engines, allowing for easy navigation and maneuverability when needed. All in all, catamarans make great vessels for vacations and traveling and can be a great way to explore the waters.

What Is The Best Type Of Catamaran For Ocean Voyaging?

When it comes to ocean voyaging, the best type of catamaran is a modern performance cruiser. These vessels are designed to combine speed and comfort, with a shallow draft for navigating in and out of shallow waters. Modern performance cruising catamarans feature two hulls connected by an open deck, often with engines that give them greater maneuverability. They also generally have larger living spaces than traditional monohulls, so they can provide more comfortable accommodations during long voyages.

How Many People Can Typically Fit On A Catamaran?

A catamaran is a type of boat with two parallel hulls. Depending on the size, it can typically fit anywhere from 4-12 people plus crew. It’s important to note that the number of passengers will depend on the size and design of the boat, so it’s best to check with a manufacturer for more specific details.

A catamaran is a great choice for those looking to explore the ocean in style. They’re spacious and versatile, making them suitable for all sorts of travel plans and excursions. Plus, they can be powered by either engines and/or sails, so you can decide which works best for your needs. Charter prices can vary depending on your vacation needs. All in all, a catamaran is an excellent choice for anyone wanting to explore the open seas!

If you’re considering renting a catamaran, it’s important to do some research first. There are many different kinds to choose from depending on what your entire party has on their travel wish list – and make sure that you have a safe and fun voyage!

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The Illustrated Guide To Boat Hull Types (11 Examples)

I didn't understand anything about boat hull types. So I've researched what hulls I need for different conditions. Here's a complete list of the most common hulls.

What are the different boat hull types? There are three boat hull categories: displacement hulls, which displace water when moving; planing hulls, which create lift at high speeds; and semi-displacement hulls, which displace water and generate lift at low speeds. The most common hull types are round-bottomed, flat-bottomed, multi, V-shaped, and pontoon hulls.

But that's all pretty abstract if you ask me, so below I'll give a simple overview of what it all means. After that, I'll give a list with pictures of all the different designs.

A Simple Overview of Boat Hull Types

Your boat hull will be the biggest factor in how your boat handles or sails, how wet it is, how bumpy - absolutely everything is determined by the hull shape. So it's important to understand what different hulls will do for you, and what each hull is best for. First, let's slice it up into rough categories.

Roughly, you can divide boat hulls into three categories:

• Displacement hulls - Lie inside the water and push it away when they move
• Planing hulls - Lie on top of the water and don't push it away
• Semi-displacement hulls - Lie inside the water and push it away, but can generate lift

Everything I'll be mentioning below is one of those three, or something in between.

There are five common boat hull types:

• Round-bottomed hulls - handle well in rough water: sailboats
• Flat-bottomed hulls - very stable for calm inland waters: fishing boats
• Multihulls - very stable and buoyant: catamarans
• V-Shaped Hulls - fast and comfortable in chop: powerboats
• Pontoon hulls - fast and stable: pontoon boats

And then there's everything in-between.

Here's a quick and handy overview of the different hull types

In each category, we find different designs and styles that have different characteristics. There isn't a real clear distinction between categories and styles: there are semi-displacement hulls and so on. So I thought the best way to learn you the different hull types is by simply creating a list with lots of pictures, instead of getting all theoretical about it.

So below I've listed all the different hull styles I could possibly think of, mention what category and type it is, the pros and cons of each one, and give you examples and illustrations for each one.

On this page:

Displacement hulls, round-bottom hull, catamaran hull, trimaran hull, planing hulls, flat-bottom hull, deep v-hull, modified-v hull, stepped hull, pontoon hull, semi-displacement hulls.

Examples: Sailboats, trawlers, fishing boats

Displacement hulls displace water when moving. These hulls lie in the water, instead of on top of it. The amount of water they displace is equal to the boat's weight. Displacement hulls handle way better in rough waters than flat-bottom hulls. That's why most cruisers have some sort of displacement hulls. There are actually all kinds, shapes, and forms of the displacement hull design, which we'll go over later.

The most important thing to understand about the displacement hull, is that it operates on buoyancy. This means that most of the boat's weight is supported by its capacity to float . Planing hulls, on the other hand, operate on lift instead, but we'll dive into that later.

Sailboats typically have displacement hulls, but also fishing boats, trawlers and crabbers. All in all, it's used for each boat that needs to handle well in rough conditions.

Learn everything there is to know about displacement hulls in this article . It lists all the pros and cons and really goes into detail on the nitty-gritty about how displacement hulls actually work .

But they are also slower than flat and planing hulls because the boat creates more resistance when moving. It has to push the water aside. In fact, this type of hull has a built-in upper-speed limit.

This upper-speed limit is called maximum hull speed . It means that the length of a displacement hull directly determines the maximum speed. It can't go faster, because the water-resistance increases with the boat's speed. To learn everything about calculating maximum hull speed , please check out my previous article here.

A round-bottomed hull is a type of displacement hull - it lies in the water and has to power through it. But since it's rounded, it creates little resistance and is effortless to move through the water. It's a very smooth ride and typical for any sailboat that sort of glides through the waves. In contrast, powerboats really have to eat their way through the water.

Examples: Canoes, sailboats

They are also one of the least stable. Since the bottom is rounded, your boat or canoe will rock plenty when boarding or moving around. They are also easy to capsize. That's why pro canoers learn to do a 360 in their canoes. I've never did a roll myself but came close enough a couple of times.

Almost all sailboats use a round bilge as well. This provides it its buoyancy and makes sure it handles well in waves. But since a rounded bilge is easy to capsize, a lot of sailboats have some sort of keel, which stabilizes the roll.

Nearly all ocean-going vessels use some sort of displacement hull, and the round bottom is the most common one. But our next guest is very popular as well.

The catamaran is similar to the pontoon hull (read on to learn more on that one), but it is a displacement multihull instead of a planing one. So it has two hulls, that lie inside the water and displace it. Like the pontoon, you will have to try really hard to capsize this design (and it won't work).

Examples: well, catamaran sailboats. But also this cool catamaran trawler:

Catamarans are extremely popular ocean cruisers. Their biggest pro is their extreme stability and buoyancy. And they have a very shallow draft for a displacement hull, making them very popular for sailing reefs and shallow waters, like the Caribbean.

Some cons for the catamaran are less agile than monohulls. They have a large turning radius, making them less maneuverable. Also, expect to pay high marina fees with this one.

Speaking of marina fees, our next one can go either way.

I think trimarans are incredibly cool, and especially the second type.

There are two types of trimarans:

• a catamaran with three hulls instead of two,
• or a displacement monohull with two floaters.

The first has the same characteristics as the catamaran: it's a displacement multihull, but now with three hulls:

The second can be a regular displacement monohull, with two pontoon-type floaters that provide extra buoyancy, making the total thing a hybrid between pontoon and displacement:

This last one has all the pros of a catamaran in terms of stability, but: you can simply wheel in those floaters whenever you head for port. That saves you a lot of money. And you can trailer her! Imagine that, a towing a trimaran home.

So those were the most common displacement hulls, aka what lives in the water. Let's move on to the planing hulls, aka what lives on the water.

Planing hulls are a hybrid between the flat-bottom and displacement hulls. Planing hulls displace water at low speeds , but create lift at higher speeds . The shape of their hull + speed lifts them out of the water, making them glide on top of the water. Most powerboats look like flat-bottom boats but use a shallow V-shape that helps the boat to handle better at higher speeds.

Examples: Water sports boat, powerboats

The most important thing to understand about planing hulls is that they operate mainly on lift instead of buoyancy. This means the weight of the boat is mainly supported by dynamic forces 1 . With the right amount of power, this design generates lift, which results in less resistance. This is why they are a lot faster than boats with displacement hulls, but also a lot rougher, even with mild chop.

A lot of powerboats use some sort of planing hull. Again, there are many designs and variations on the planing hull, and I'll try to mention as many as I can below.

Because the wedge of the hull runs into the water, it is much easier to handle at high speeds. At lower speeds, it is able to keep its course, even with a bit of wind. However, whenever the boat starts planing, it is prone to wind gusts, since the wedge shape no longer stabilizes the boat.

The flatter the hull, the faster it will go, but also the more poorly it will handle. Other powerboats use deep V-hulls, which I'll discuss below. But first, let's take a look at the flattest hulls you'll ever see.

A flat-bottom hull lies on top of the water and doesn't displace water (okay, very little) as it moves. Since there is no displacement, there is also little to no friction when moving. This makes it potentially fast, but it handles pretty poorly. It is one of the most stable hull design.

Examples: rowboats, (old) high-performance powerboats, small skiffs, small fishing boats, tug boats

They aren't just incredibly stable, they're also very practical. Because the bottom is practically flat, they maximize boat surface. But they are also extremely choppy in rough weather and waves. They will handle very poorly with stiff winds, as the wind can simply catch them and blow them across the water surface. That's why this design is almost exclusively used for calm, small, inland waters.

This type of hull operates mainly on buoyancy , like the displacement hull, but it doesn't require the same amount of power to propel, which is why it's faster.

Because of the uncomfortable ride, not a lot of boats use a perfectly flat bottom. Most boats nowadays use some sort of v-hull or hybrid design, like a semi-displacement hull; especially larger boats. So not a lot of boats have a real flat bottom. However, we do call a lot of boats flat-bottomed. How come?

There are two types of hulls we call flat-bottoms:

• Of course boats with an actual flat bottom
• Boats with almost no deadrise

What is the hull's deadrise? The deadrise is the angle of the front of the hull to the horizontal waterline.

As you can see, the green sailing dinghy in the picture above has a deadrise that's barely noticeable.

Let's move on to other variations of the planing hull. One of the most popular hull design for modern-day powerboats is the Deep Vee hull. And that's as cool as it sounds.

This is a type of planing hull that combines the best of both worlds.

These types of hulls are very popular on modern-day powerboats, and no wonder. With a V-shape that runs from bow to stern, deep into the water, you can handle this boat even in offshore conditions. It handles a lot better than flat-bottomed hulls, while it's at the same time extremely fast.

Examples: Most modern powerboats.

The Deep V-shape acts as a tiny keel of sorts, stabilizing the boat and making it more reliable and maneuverable. The rest of the hull acts as a planing hull, giving the boat its fast edge. Even at high speeds, the Deep V will cut into the water, making it more handleable.

The deep-V design is just one of many variants on the V-hull. Below we'll talk over another, the modified V hull.

The modified V hull is the ultimate crossover of all planing hull types. It's a mix of the flat-bottom and Deep V hull. It is one of the most popular hull designs for small motorboats. It's flat in the back and then runs into a narrow V-shape to the front. The flat back makes it more stable, and adds a little speed, while the V-shape front ensures good handling.

It is, in short, kind of the compromise-family-sedan of boat hulls. It's the fastest design that's also stable, that's also safe, and that also handles well. But it's not the best in any of those things.

Most powerboats you've seen will have some sort of Vee or Modified-V hull.

Stepped hulls are used on high-performance powerboats. It's a type of planing hull that reduces the hull surface by adding steps, or indents in the hull below the waterline. It looks something like this:

It is said to work extremely well at high speed (60 knots and up) and adds up to 10 knots to your top speed.

On to our next design. There are also planing multihulls, and they might even look like catamarans to you. Meet the pontoon hull.

Pontoon hulls float on top of the water using pontoons or floaters that create lift. It's a type of planing multihull that doesn't lie in the water, so it doesn't displace a lot of water. They don't really handle well. As with any multihull, they aren't agile - they're not great at maneuvering. They also have a very large turning radius. But they are extremely stable: there's no chance you'll capsize this.

Examples: Cruisers, modern trawlers, motor yachts, Maine lobster boats

Semi-displacement hulls are smack bang in the center of planning and displacement hulls. They are a bit better for speed than displacement hulls are. They are a bit better for handling rough waters than planing hulls are. This makes them very versatile.

You can see these a bit like being 'half-planing' hulls. These hulls are designed to plane at lower speeds than normal planing hulls - somewhere in the range of 15 - 20 knots, depending on the length of the boat. It also requires less power. When the hull lifts, it reduces drag (water resistance), making it faster and more efficient.

Semi-displacement hulls are perfect for boats that need to be steady and seaworthy but fast at the same time.

For more information about semi-displacement hulls, please check out my in-depth guide to semi-displacement hulls here . It has a diagram and lists all the pros and cons.

So those were my 11 examples, and my step by step explanation of the different types of boat hulls and functions. You now have a solid basic understanding of boat hulls, and can recognize the most common ones. I hope it was helpful, and if you want more good sailing information, be sure to check out my other articles below.

https://www.soundingsonline.com/boats/how-different-hull-types-react-in-rough-water .  ↩

I was wondering what your opinion would be on the ship uss Texas as far as hull type and bow type. I think it has a plumb bow and it looks to have a displacement or flat bottom hull. Im doing some research and a better trained eye would be of great help. I used images “bb-35 dry dock” to help see the hull shape. Thank you

Shawn Buckles

Hi Kirk, I don’t know about trained but here we go. I’ve checked the picture, it’s definitely a displacement hull I’d also say it’s a plumb bow.

Hahahahaa imagine liking boats hehehehehe Extremely stable & faster Handles well in rough water Extremely stable & faster Handles well in rough water Extremely stable & faster Handles well in rough water Extremely stable & faster Handles well in rough water Extremely stable & faster Handles well in rough water Extremely stable & faster Handles well in rough water Extremely stable & faster Handles well in rough water Extremely stable & faster Handles well in rough water Extremely stable & faster Handles well in rough water

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You may also like, a complete guide to displacement hulls (illustrated).

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What Are Catamarans And Their History?

Catamarans are boats with two connected hulls that are joined by a bridge. Because they are faster, more stable, and capable of carrying larger cargo than their monohull counterparts, catamarans are growing in popularity.

As a result, designers and owners have greater freedom to accommodate space needs in terms of size and usefulness than they would with single-hulled vessels.

The name catamaran came from the Tamil word “kattumaram” which basically meant “logs which were bound together”. These traditional watercraft were basically used on the south coast of India and Srilanka. They were dated back to as early as the 5th century when they were used to transport troops from one island to another.

Let us get into more details to learn more about the different types of catamarans and their functions.

What are the different types of catamarans?

Catamarans are mainly divided into two categories: sailing and power catamarans, however, both categories can be split into smaller groups by their size and use.

Sailing catamarans

These types of catamarans are mainly propelled with help of sails. The sails act as wings with which the vessel moves forward with the help of wind energy. The sailing catamarans have advanced significantly in recent years in terms of both design and performance attributes. Sailing catamarans are further subdivided based on their dimensions and functions and are classified into,

Small, mini, or sports catamarans

Depending on the size, these are also known as leisure catamarans and can carry a load of 6 persons on average. You’ve definitely seen some of them speeding through your local beach waters on hot, sunny weekends; some of them are made to be driven by one person. Those designed for use in sports have a trapeze that enables one to hike out and serve as a counterweight.

Small-day sailing cats are well-liked because they offer a secure and straightforward learning environment, and you can see fleets of them in resorts where guests with little to no sailing experience utilize them. These little cats are often made of roto-molded plastic or fiberglass, and as they frequently lack auxiliary motors, sails are their only means of propulsion

A trampoline that spans the two hulls of the sports catamarans acts as a bridge so that individuals can move from one to the other without falling into the water. They may be launched and landed from a beach as opposed to a dock because of their modest size. They have a rotating mast and a mainsail with full-length battens.

Cruising Catamarans

In the worlds of long-distance cruising and bareboat chartering, larger cruising cats have dominated. These are more stable than their monohull competitors, allowing them to securely transport people across continents. These are more stable than their monohull competitors, allowing them to securely transport people across continents.

For maneuverability, charter cats frequently have two engines—one in each hull—as well as a mast that holds a mainsail and at least one headsail.

Nowadays, cruising catamarans are more widely available than monohulls at bareboat charter firms with tropical bases, and those numbers are rising in places like the Mediterranean.

Power catamarans

Power catamarans, often known as “multi-hull powerboats” or “power cats,” are vessels without masts or sails but with larger and more powerful engines. They can be the most perfect choice for your first boat if you enjoy offshore fishing or other water sports. You get a great balance of performance, stability, and maneuverability with these powerboats. Power cats come in a range of different sizes and shapes. In terms of dimensions and functions, they are also divided into,

Center console fishing catamarans

The fishing industry is flooded with smaller power cat brands, while bareboat charter and cruise platforms are seeing the emergence of larger ones. The multi-hull performance boat frequently has a center console driver layout.  They can reach higher top speeds thanks to their higher horsepower, but these cats also need to be strengthened hulls to support the weight and power of these engines.

When used for fishing, normally lesser than 50 ft, there are several options available for live wells, rod holders, gear storage, and built-in coolers for both fish and beverages. Depending on the length and design elements of the boat, certain consoles may locate closer to the bow or aft of the vessel.

Offshore powerboat racing catamarans

Offshore powerboat racing is the aquatic equivalent of off-road auto racing. Since its inception in the late 1960s, offshore racing has changed drastically.

Though V-bottom powerboat classes still exist, twin-engine catamarans with top speeds of 170 MPH in the most powerful classes dominate the sport.

The offshore race course may be the most dynamic setting in all of the motorsports because of the constant fluctuations in a swell, wind, tide, current, and other factors. The track might abruptly change from being friendly to antagonistic.

These boats are designed and built such that they are both lightweight but extremely strong using the most advanced materials like carbon fiber and Kevlar . Manufacturing methods such as infusion are adopted to make sure the properties of the materials are not lost during the production stages.

Motor yachts and ferries

For their roominess and speed, catamaran designs have also become popular among motor yachts and commercial passenger ferries. These cruise-centric yachts offer homelike livability for avid travelers, are fuel efficient, and are fairly intuitive to run.

Motor yacht catamarans have been designed with larger living spaces in mind, as well as more outdoor recreation places. The huge fly bridges provide additional space for relaxing and socializing, and electric boat davits make lifting the dinghy simple. Daily tasks like cooking can be done with ease because catamarans don’t heel.

Why Is There A Shift In Trend From Monohulls To Catamarans?

Recently, more and more often you can find catamarans in the harbors of large cities and small resorts. It can be unequivocally argued that catamarans are gaining popularity among both beginners and experienced sailors and even celebrities. But what makes them gain this popularity?

Catamarans In Terms Of Function And Utility

The enormous interior space expansion can provide the owners considerably more freedom to select furnishings without regard to size limits and more room for additional appliances like washers and dryers, which can make life on board much easier.

Due to their broader decks and roomier interiors, catamarans are frequently employed as party boats. The deck can accommodate more people without giving them the impression of being crammed into a small space.

In terms of storage, catamarans offer more alternatives than monohulls because both hulls can serve a variety of purposes, increasing the vessel’s overall capacity as well.

Catamarans are typically utilized as party boats since they have bigger deck spaces and greater room for movement. The deck can also accommodate more people without giving them the impression of being confined in a small space.

If any equipment breaks down, there is always a backup. For instance, if one of the engines on the port hull fails, we can always use the starboard engine to re-enter landfall. Likewise, if a generator breaks down, there is always a second generator that can be utilized as a backup.

Catamarans In Terms Of Performance And Stability

Due to the narrow hulls of catamarans, which serve to reduce drag forces, they frequently outperform monohulls. On performance power catamarans, the area in between the two hulls known as the “Tunnel” is built in a similar way to an aerofoil so that it behaves like a wing, boosting the aerodynamic lift forces and enhancing the overall effectiveness and top-end speeds of the craft.

Due to their stronger lift forces and lower water friction than monohulls, catamarans typically have a better fuel economy. This is because the strain placed on the engines as a whole is reduced, resulting in less fuel being used.

In terms of roll stability, catamarans are often more stable than monohulls. This offers them an advantage in terms of comfort and the ability to carry out various activities onboard the vessel with ease, as well as lowering the possibility of passengers falling on board. Because they are less likely to make passengers seasick, catamarans are typically used as ferries or passenger ships.

Catamarans provide a more comfortable ride whether they are in shallow water, deep water, or at anchor; they have a decreased chance of keeling over or capsizing in heavy winds.

Also, catamarans have a much lower draft when compared to their mono hull counterpart’s allowing them to easily ply over shallower waters.

What Are The Potential Drawbacks Of Catamarans?

Catamarans have a few minor limitations, much like any other kind of boat:

Finding dock space is frequently challenging and expensive for catamarans because they take up more room.

Power and sailing cats can both smash into the bridge deck when heading to the weather because of the way that they are built.

Additionally, because they have two hulls instead of one, sailing cats can’t necessarily aim as high into the wind as monohulls can.

Overall, a catamaran allows for greater speeds, but at the expense of much-reduced vessel control. Knowing when to accelerate and when to slow down is difficult when sailing a catamaran. A catamaran can be readily overturned in sea conditions that a monohull can maneuver securely in.

Finally, while it may be alluring to add more weight in a catamaran due to the space it provides, doing so will almost certainly degrade the performance of either power or sailing cat—something that is less of an issue on their monohull counterparts.

Catamarans are a growing trend due to their better advantages over their monohull counterparts. Despite having an ancient fundamental design, catamarans are a modern boating alternative that can be used by any boater for both commercial and leisure uses.

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About the author

I worked as an officer in the deck department on various types of vessels, including oil and chemical tankers, LPG carriers, and even reefer and TSHD in the early years. Currently employed as Marine Surveyor carrying cargo, draft, bunker, and warranty survey.

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How Many Hulls Does A Catamaran Have?

Last Updated by

Daniel Wade

August 30, 2022

‍ Catamarans are some of the most well-regarded sailboats on the water, and they offer numerous handling advantages over monohulls. But how many hulls can a catamaran have?

All catamarans have two hulls arranged side-by-side. Catamaran hulls are separated by a gap that is many times wider than the hulls themselves. Outriggers, which have a large primary hull and a small outer hull, or sometimes considered catamarans as well.

In this article, we'll go over how many hulls a catamaran has, how they're configured, and how they compare to other common single and multihull boats. Additionally, we'll cover why catamarans are designed the way they are and go over the advantages and disadvantages of the catamaran design. We will also cover common lookalike vessels and how to distinguish them from catamarans.

We sourced this information from widely used sailboat design and identification guides, along with our own experience in the sailing community.

Table of contents

‍ Catamaran Hull Configuration

The hull configuration of a catamaran is simple and easy to identify. Catamarans Have a wide stance and consist of two identically shaped narrow hulls connected at the tops. The hulls are an exact mirror of each other, and there's a large space or platform in between them that provides room for a cockpit, living spaces, and even a trampoline.

Catamarans vary widely in shape, size, and configuration. However, it's easy to spot a catamaran by simply counting the hulls. Any sailboat with two identical hulls side-by-side is a catamaran. A sailboat with a large primary hull in a small outer hull is likely an outrigger, which is a rare type of catamaran.

Why Do Catamarans Have Multiple Hulls?

Catamarans have multiple hulls for speed and stability. The stability advantages of incorporating two narrow hulls and spacing them widely apart are easy to identify. This wide stance makes it very difficult to tip a catamaran in either direction, which increases sailing comfort and significantly reduces rolling in heavy seas.

Speed is another reason why catamarans have two hulls. Catamarans can travel at much faster speeds than monohulls because they're not bound by the rules of hull speed. When a monohull travels through the water and creates a wake, the bow and stern waves will synchronize and interfere with the speed of the boat. When these waves synchronize, the monohull has great difficulty traveling any faster.

Catamaran hulls also generate wakes, but the two side-by-side hulls effectively cancel out the synchronous interference that slows monohulls down. Additionally, the narrow design of the hulls allows them to pierce through waves instead of riding over them, which reduces travel distances and increases efficiency.

Another reason why catamarans have two hulls is that the design reduces draft. The draft is a measurement of how deep in the water the hull extends, and catamarans have some of the shallowest draft-to-length ratios in the sailboat design world. That means that a comparatively large catamaran can travel in much shallower water more safely than a monohull.

Are There Other Multihull Sailboats?

Catamarans are the most common multihull sailboat design, but there are several others available as well. The most common multihull other than the catamaran is the trimaran. As the name suggests, trimarans have three hulls instead of just two. The trimaran usually has two narrow hulls and a larger hull in the center, as the primary purpose of the outer hulls is to provide stability.

Catamarans and trimarans are known for speed. And while catamarans can double or even triple the speed of an equivalently-sized monohull, trimarans can go even faster. This is because trimarans are not bound by the rules of hull speed either, and they create less drag-inducing hydrodynamic interference than catamarans.

Catamaran vs Monohull

Catamarans have a number of distinct advantages over monohull sailboats. The most obvious benefit to experienced sailors is the increased stability of the multihull design. Picture it like a table. A table with wide legs is going to be more stable than a table with narrow legs. Leaning on it won't knock it over as easily—and the same is true out on the water.

Catamarans can also be more spacious than monohulls, without additional size in terms of length. The catamaran is a very old design, as even ancient boatbuilders knew of its advantages. However, there are some downsides to catamarans and other multihull designs, which is why monohulls are still the most common kind of sailboat on the water.

Monohulls are easy to construct. Unlike a catamaran, which must have a carefully designed load-bearing structure connecting the hulls, monohull sailboats derive all of their strength from the hull itself. In other words, there aren't as many weak points, and it's easier to build. Additionally, it's also a lot cheaper to build a monohull, in the design doesn't have to be quite as precise.

Another advantage of a monohull sailboat is that it's easy to configure the interior. If you need more space for accommodations, engineers can simply widen the hull during the design phase. Catamarans have very narrow hulls comparatively and can be hard to effectively utilize space without unnecessary redundancy or cramped quarters. Monohulls are also much more efficient for transporting cargo, as the hulls are wide enough to fit a vast amount of material.

Catamaran Hull Size

Catamarans come in all shapes and sizes. And unlike monohulls, overall length is not the primary deciding factor when it comes to performance. When you picture a catamaran, you're probably thinking about one of the large glossy cruising sailboats that often dot coastal anchorages across the world. These vessels usually range in size from 35 to 55 feet in length.

There are different types of catamarans. The most common kind, known as cruising catamarans, or usually around 45 feet in length. The smallest cruising catamaran is around 30 feet long, as catamarans don't have enough hull for comfortable accommodations at a size smaller than this. Cruising catamarans can reach astounding sizes, often exceeding 50 or 60 feet in length.

The beam, or width, of catamarans, is usually much more significant than monohulls of the same length. This is despite the fact that catamaran hulls are significantly more narrow than other types of vessels. For example, a 40-foot monohull likely has a beam between 10 and 14 feet, whereas a 40-foot catamaran can have a beam of 20 feet or more.

These factors have a positive effect on seaworthiness, as catamarans don't heel over under heavy sail and are extremely difficult to capsize. Additionally, they will float just as well upside down as they do right side up.

However, this additional beam can make docking a catamaran challenging. Marinas that can normally accommodate two large monohulls in a slip can only fit one catamaran in the same space, leading to increased mooring fees.

What Are Catamaran Hulls Made Of?

Catamaran hulls are made from all sorts of materials. The most common catamaran designs use fiberglass, which is a moldable mixture of hard glass fiber and waterproof resin. Fiberglass has been the primary recreational boat building material across the world for more than 60 years, and the technology is better than ever. Fiberglass catamaran hulls can theoretically last forever, they can be molded into any shape at the factory, and they're easy to repair.

The finest custom cruising catamarans are made from aluminum. Aluminum is an extremely costly but highly desirable catamaran building material, as it reduces weight and allows these vessels to reach extremely high speeds. Due to the cost and technical experience required to build an aluminum catamaran, the vast majority of boats are fiberglass.

Wood is occasionally used to build catamaran hulls. Today, most wooden catamarans are made from marine plywood and sheathed in a layer of fiberglass for strength and waterproofing. Traditional wooden construction is only found on outriggers, as it is costly and very time-consuming.

What Are Outriggers?

Outriggers are a type of catamaran that traces its roots all the way back to 3000 BC. An outrigger is a simple open boat with a stabilizing hull mounted off to one side. Some outriggers, especially canoes, have two stabilizing hulls.

Outriggers, while technically catamarans, are not widely used in the 21st-century due to their lack of space and one-sided stability. However, these vessels are an important part of catamaran history and a great demonstration of how multihull designs can add great stability to a boat.

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I've personally had thousands of questions about sailing and sailboats over the years. As I learn and experience sailing, and the community, I share the answers that work and make sense to me, here on Life of Sailing.

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Catamaran Or Monohull? 27 Important Facts (Explained)

Catamarans and monohull boats are two very different kinds of vessels.  Each craft offers distinct advantages and disadvantages that you’ll want to consider before choosing between the two.

In this post, we’ll go over some of the important things to consider when choosing between catamarans and monohull boats:

Table of Contents

Cost & Availability

Both catamarans and monohull boats come in small recreational sailing versions, larger motorboat versions, and larger sailing models.  In all cases, the catamarans will cost more and will be harder to find.

The reason catamarans are harder to find because there are not as many of them, and they’re mostly made overseas.

Also, there aren’t as many catamaran manufacturers, so sailors have fewer options when buying them.

On top of this, catamarans have only recently become popular in the United States and other areas of the developed world.  This means the used market for boats doesn’t have as many catamarans on it.  You might find that you have fewer options when making a used catamaran purchase, which could bring costs up to a premium.

Two Times The Fun with Catamarans

Another reason that catamarans are more expensive than monohulls is the fact that catamaran buyers have to purchase two hulls, two engines, and two of all of the components that help make an engine work.

Traditional sailboats and large powerboats with one engine don’t have this cost issue.

On top of this, a catamaran is much wider than a monohull, and thus you have more space to build and equip.

On the other hand, once you’ve purchased the boat, you do get to enjoy the benefits of having two of everything.  We’ll talk about the advantages of this further down in this post.

Maintenance Cost Makes A Difference

The maintenance on a catamaran is also more expensive than the maintenance on a monohull boat.  This goes back to the fact that there is twice as much of everything to maintain.

Catamaran owners will need to do preventative maintenance on two different engines, and they’ll have two hulls and a large deck area to clean and maintain as well.  If they’re getting the bottom of the boat treated, they’ll have to do this twice (once for each hull).

Even the interior components can usually be found twice.

Each cabin will usually have a head in it, so you’ll have at least two toilets and sinks to maintain, which obviously has its plusses and minuses.

One positive aspect of this is that catamaran owners do have the option of deferring some of their maintenance.  For example, if one head is no longer functioning properly, you always have the second one that you can use.

It also adds a bit of safety as well.

This is because while the catamaran does have two engines to maintain, the owner does have power even if one of the engines happens to go down.

Some catamaran owners also like to point out that maintenance may not have to be done as frequently.  This is because the engines don’t have to work quite as hard, and other items like additional bathrooms and sinks might only be used half as much.

How Much Space Do You Need?

A catamaran has more space than a monohull.  This is because the boat is wider, and it has a much larger deck area.  It also has twice as many hulls, so you have more overall space between the two of them.

The additional space is great for people looking to throw parties on their boats.

Most boat owners would agree that the catamaran is usually the party boat of choice at the docks.

Even if you aren’t into throwing parties, the extra space can still be nice for relaxing on the deck or getting a suntan.  The wide-open space also makes it easy to use the boat as a fishing platform.

Additionally, you have more space for stuff like surfboards, rafts, and other items that can easily clutter up the deck of a monohull.  Even fishing can be easier from a catamaran as the deck provides plenty of space between different anglers.

Catamaran owners also have additional space for carrying fresh water and adding generators and solar panels.

Interior space is generally more plentiful on a catamaran, and luxury catamarans have an easier time fitting large items like washers and dryers inside of them.  You can have these on larger monohulls as well, but it will be harder to make them fit than it is in a catamaran.

On the other hand, all of the additional space means the catamaran owner has more space to maintain and clean.  Also, all of the additional items that can be brought onto the boat will make it heavier.  A heavier boat will use more fuel, and it will travel more slowly.

Living Quarters Vary Between The Two

The living quarters on a catamaran are much different than they are on a monohull.  Most people would agree that the berths in a monohull are much more spacious than in a catamaran.

A monohull offers people the opportunity to have a large bed with space on either side to walk around it.  This is great for couples who want to get out of bed without waking up their partner.

Catamarans, on the other hand, have the advantage of being able to offer large above-deck salon areas.  The galleys, the dining areas, and the living areas can all be above-deck, while the two hulls can provide heads and berths.

Some boat owners say that living in a monohull is akin to living in a basement apartment .  Other boat owners prefer the monohull because it brings them closer to the water and gives them the feeling of being at sea.

Privacy Can Be Prioritized On Catamarans

A catamaran offers up many different living areas that people can take advantage of.  For example, each hull will typically have its own bathroom and bedroom.

This gives each sleeping area complete privacy from the other.

The living quarters are usually up on the deck, so early risers can wake up and move to these quarters without waking up the others.

The same holds for night owls.  A night owl can stay up late without bothering the people who want to retire to their beds earlier.

With two hulls, large catamaran owners can hire a crew and give them their own hull to live in so that there is separation between the cruisers and the crew.  This is a wonderful advantage for honeymooners looking to have their own space.

The downside to all of this, of course, is that sometimes a family may not want the additional privacy.  For example, a family with small children might not want their children in a different hull than they are.

Additionally, the extra privacy can make it hard for people on the boat to communicate.  This could become a big problem in the event of an emergency.

For this reason, it is often recommended that each hull have a radio in it so that the occupants can quickly communicate with each other.  Remember, even in inland areas, cell phone reception may not be very good inside the boat hulls.

Recreation In a Monohull vs. a Catamaran

Most sailors agree that sailing a monohull boat is much more exhilarating than sailing a catamaran.  Traditional sailboats heel, and sailors get instant feedback while they’re sailing.  For the most part, catamarans stay stable, and you don’t get the same feeling with the movement of the wind and the water.

When it comes to monohull powerboats, you have the advantage of being able to pull water skiers, kneeboarders, and tubers with ease, as long as the boat has the power and a planing hull.  A power catamaran usually doesn’t have the speed or maneuverability to pull off these recreational opportunities because they are displacement hull designs.

Catamarans excel in more leisurely recreational activities.  A catamaran makes a great party deck as well as a great cruising deck.  Catamaran owners can comfortably walk around a catamaran without having to worry that the boat might knock them over the next time it decides to heel.  This allows boaters to sit and talk with one another comfortably.

A catamaran can also be used as a beaching vessel.  This makes it a great platform for people looking to go swimming or fishing around sand bars and other shallow water areas.  It also makes it a great boat for sailors looking to sail a larger boat on a river or lake known for having shallow areas.

Swimming and Diving

Swimming and diving off of a catamaran are usually much easier than doing the same from a monohull.  The wide stance of the two hulls offers boat designers the option to put in staircases at the back of both hulls.

In between these staircases, some boats will have an additional diving platform and/or a dedicated frame for pieces of equipment and dinghy storage.  This makes catamarans great for swimmers, snorkelers, and divers.

On the other hand, modern monohull sailboats can also have good transom stairs for easy access to the dinghy and swimming.  Both types of boats can easily travel far out to sea, giving boaters the option of diving in areas that can’t be accessed from beaches and developed areas.

Boat Draft In Shallow Waters

For the uninitiated, the boat’s draft refers to how deep the boat’s hull sits within the water.

A monohull typically sits deep within the water, while a catamaran sits much higher on the water.  This is why we stated that a catamaran is good for shallow waters.

The advantage of having a boat that can go into shallow waters isn’t restricted to just recreational activities like swimming and fishing.  A boat that can go into shallow water is safer to operate in areas where a boat with a deeper draft might become damaged.

Additionally, a catamaran has more stability on calm waters.  This helps make a catamaran more comfortable to relax or sleep on while at anchor or the dock.

The deeper draft of a monohull boat has its advantages as well.  A deeper draft provides more stability in rough waters and allows a boat to go further into the sea.

For this reason, many coastal cruisers will prefer catamarans, while many ocean voyagers will prefer monohull boats.  In fact, some areas of the Caribbean and the Florida Keys can be off-limits to boats with deep drafts as it simply isn’t safe for the boat to navigate these waters.

This isn’t to say that you can’t navigate these waters in a monohull boat, but you will have to be cautious depending on how deep your monohull’s boat draft is.  You wouldn’t have this issue in a catamaran.

Stability On The Sea

A catamaran offers a lot more stability in shallow waters, in calm waters, at the dock, and anchorage.  This makes the boat great for cruising and for relaxing in port.

A monohull offers a lot more stability in rough waters.

This makes this boat great for heading out to sea and for navigating vast distances.

Safety Issues To Consider

Both catamarans and monohulls can be built to navigate the waters they were made for safely.  This will be determined more by the boat’s category designation rather than the type of boat.

However, each boat deals with unsafe situations in different ways.  For instance, a monohull boat is likely to right itself if it is capsized.

This means that even in rough seas, you’re unlikely to find yourself permanently capsized.

The downside to this is that should you become completely swamped from a capsize in a monohull boat, you are much more likely to sink.  In fact, if there is a hull breach on a monohull boat, your boat could sink.

Catamarans are said to be unsinkable.  This isn’t completely true, but it is very unlikely that a catamaran will sink.  Even if a hull is breached, you still have a second hull to keep the catamaran afloat.

However, a catamaran can’t right itself.  If you capsize your catamaran, it will stay capsized.

One other safety concern to consider is that a monohull sailboat will heel while a catamaran will not.  This increases the chances that someone could fall off the boat or onto the deck in a monohull boat.

Catamarans Are Faster Than Monohull Boats

A catamaran is faster than the average monohull boat.

This is because they face less water resistance, and their narrow hulls don’t have to deal with their own bow waves as a monohull does.

Of course, catamarans aren’t always faster.  Old cruising catamarans may not go faster than 8 knots, and modern monohulls can exceed 10 knots.

Monohull boats tend to sail downwind and in choppy seas better than catamarans.  This gives them a speed advantage during ocean voyages.

We have a separate post with complete average speeds per type of catemaran . It’s a must read if you are at all concerned about speed!

Fuel Consumption Considerations

Catamarans have two engines to burn fuel, which can drive up fuel costs.

However, a catamaran is lighter on the water, so it usually takes less energy to move a catamaran.  This means you’ll end up using less fuel in a catamaran than you would in a monohull.

On top of this, catamarans can decide to use just one engine in low wind areas.  This further decreases the amount of fuel that a catamaran consumes.

These rules only apply to calm waters.

A monohull navigates waters with high waves and strong winds much more efficiently than a catamaran.  In this case, you’ll use less fuel in a monohull than you would in a catamaran.

Sailing Differences To Notice

Sailing a monohull boat can be exhilarating.  These boats can glide through choppy waters, and you get to feel the motion of the boat as the sea rushes by the cockpit and the wind causes you to heel.

This type of sailing also provides instant feedback as you’ll know what you need to do with the sails as you’ll feel what is going on through the boat’s motion.

Sailors all over the world have been using monohull sailboats for years, and you’ll find plenty of outlets for recreational sailing with a monohull sailboat.

Sailing catamarans do not heel like a monohull sailboat.

These boats, therefore, do not provide the sailor with instant feedback.  Also, if you incorrectly sail a catamaran, you do risk capsizing the boat more easily.

Training Can Be Quite Hard

Sailing a catamaran and sailing a monohull boat are two different experiences.  People looking to sail either should probably get professional training.

Obtaining this training will always be easier with a monohull boat.

This is because monohulls are more popular, so you’ll have more instructors available to you.

Do You (Or Your Friends) Get Seasick?

People who are prone to getting seasick easily might want to consider a catamaran.  A catamaran provides much more stability in calm waters, and you get a lot less movement.

On the other hand, people who are not prone to getting seasick might prefer a monohull in choppy waters.

This is because a monohull will deal with deep and choppy waters with high waves much better than a catamaran will.

As a result, a catamarans movement can seem extreme under these types of conditions.  People who have never gotten seasick before can end up sick under these conditions.

Here’s a separate article we wrote with everything you should know about seasickness on Catamarans . There are some things you can do and some things you should know!

Docking Is (Usually) Easier With A Monohull Boat

Docking a catamaran can be a difficult endeavor.

This is because catamarans are often too wide to be docked within the slips located in central areas of a marina.

Because of this, they need to be docked at the end of the dock.  This leaves them with fewer spots to dock.  It also makes docking more expensive.

Catamaran owners traveling through areas that are unlikely to have many catamarans in them may find it difficult to find a dock at all.  This is true in areas of the northern Atlantic where monohulls are much more popular than catamarans.

Storage Issues To Consider

Even storing a catamaran can be more difficult.  This is because storage facilities often do not have the equipment to get a catamaran out of the water.

The wide width of these boats requires special lifts, and not all boat marinas will have them.

Storage facilities that do get the catamaran out of the water will often charge more money for it.  They’ll charge additional fees for taking the catamaran out of the water, and they’ll charge additional fees for the actual storage of the boat as well.

Redundancy And Backup Equipment

We touched upon this earlier, but it is worth repeating that catamarans have many redundancy built into them.  This can be a big advantage when it comes to safety.

For example, if one rudder becomes inoperable, the boat can still be steered with the other one.  If one engine becomes inoperable, the boat can still be driven with the other one.

In extreme cases, a hull could become damaged, and you could still stay afloat because the other hull will keep the boat safely above water.  These safety advantages can save lives and keep people from becoming stranded out at sea.

The primary downside is the maintenance issue that we mentioned earlier.  All of these redundant components will need to be maintained.  As a result, maintenance costs will be close to twice as expensive in a catamaran.

Cooking Is Easier On Catamarans

Cooking on a catamaran is usually easier than it is on a monohull.  The main reason for this is that a catamaran doesn’t heel like a monohull, so you don’t have to worry as much about things falling over.

This not only makes cooking easier, but it makes cooking safer as well.

Additionally, catamaran galleys tend to have more space in them to move around.  Also, they are often up on the deck, so you don’t have to climb in and out of the hull with your dinner in hand.

Dinghy Storage

Monohulls and catamarans can both hold dinghies.  The larger the boat, the larger the dinghy can be.

However, catamarans have a wide area at the rear of the boat that is perfect for holding dinghies.

This makes getting in and out of the dinghy easier.  Also, people can often have larger dinghies on their catamarans because the boat’s stern is so accommodating.

Power Generation Is Easy On A Catamaran

A catamaran has a lot of space for solar panels and wind turbines.  Rigid panels can be placed in areas that won’t be walked on, like overtop of the bimini, and flexible panels can be placed in areas where the panels might end up getting stepped on.

The width of a catamaran even gives them more opportunities to put hydro generators into the water.

This means catamarans can generate more power than the average monohull boat can generate.

On the other hand, a monohull usually has less powered items to worry about.  Monohulls need less power to operate at full capacity, so you may not need all of the additional space for generating power.

Ventilation Issues To Think About

Some people feel that monohull boats don’t offer enough ventilation.  This is especially true in warmer areas of the world.

Catamarans also lack ventilation within their hulls, but fortunately for them, much of the living space is located up on deck.  This gives catamarans an edge when it comes to cruising in warm weather.

On the other hand, monohull owners aren’t exposed to the cold winds that you might find up on deck in harsher climates. 

This lack of airflow may actually be of benefit in this instance.

Some people find monohulls to be better looking than catamarans and vice versa.

This all comes down to personal preference, so you’ll have to decide for yourself which type of boat has the advantage in this case.

Some people think catamarans are the most elegant thing in the world while others prefer monohull boats as they look more classic.

Resale Value Is An Important Factor

If you read our extensive guide to boat depreciation per boat type , you know that no matter what boat you buy, it will always go down in value.  This is just a sad fact of boat ownership that people need to consider before buying a boat.

Many factors go into how much you’ll be able to get for your boat when you resell it.  These factors are the condition of the boat, the age of the boat, and the economy in general.  For example, people are less likely to want to buy boats during a recession.  This is especially true when it comes to smaller boats.

However, one additional factor that catamaran owners need to consider when thinking about resale value is the value of the dollar. 

People from the United States don’t have many American catamarans to choose from and will usually need to buy these overseas.

This means that a catamaran will be less expensive to buy when the dollar is strong compared to the Euro and more expensive to buy when the dollar is weaker in comparison.  This will affect the used market as well because higher values on new catamarans can help to bring up the value on the used market.

With a monohull boat, you may not have to consider situations like this as there are makers of monohull boats all over the world.

Don’t Let The Length Trick You!

One thought to keep in mind when comparing monohull boats and catamarans is that their different shapes account for different space advantages.

For example, a 40-foot long catamaran will have much more cubic space than a 40-foot long monohull.

Because of this, when comparing boats, you should look at the cubic space rather than the length. In this case, you may be comparing a 48-foot long monohull with a 40-foot long catamaran.

When you compare the two types of boats in this manner, the price differences aren’t quite as large, and the comparison is fairer.  It also may make the operating and maintenance costs more similar.

This is an important distinction to make because the length of the boats can trick you!

Consider Trying Both (Before Buying)

Boats can be an expensive purchase, so it makes sense to try them out before you decide to make your purchase.

Rent each type of boat and use it on the types of waters that you intend to cruise on the most.

Try the boat out in different weather conditions as well, and don’t be afraid to do multiple rentals before you make your final choice.  The time and money invested into making sure you get the boat you really want will be more than worth it in the end.

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Catamaran Beam to Length Ratios Explained: For Beginners

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Starting my sailing career something that struck me was the wast number of weird words and strange terminology, no longer was a rope just a rope, it’s a halyard or a sheet. In this article, I will explain one concept that is important to understand for anyone trying to buy a boat or for someone who wants to better understand the limitations of the vessel they already have.

Catamaran beam-to-length ratios are mathematical representations of the difference between the length of a sailing vessel and its width. There are multiple beam to length ratios, some impacts stability (Bcl/Lwl), and the amount of sail the vessel is able to carry. Others are used to calculate exterior space (B/L). In general, a narrow boat will be less stable but weigh less and cheaper to build.

Most modern catamarans have a beam to length ratio of >50%. You can easily calculate this on your own by following the steps below. But first, let’s check out some more terminology to make sure we really understand this ratio.

Table of Contents

Nautical Terminology

No matter how much you love the ocean, you will have limited success if you are unfamiliar with the words that go with adventuring out on it. I need to clarify some nomenclature before we delve into the ins and outs of ratios and catamarans (and monohulls).

• Beam overall (Boa): is the width of a boat at its widest point. The wider a ship’s beam, the more interior and exterior space. this allows for more gear and and better living accomodations.
• Draft: sometimes spelled “draught,” is the measure of how deep your vessel “sits” in the water. Catamarans have shallower drafts than monohulls, meaning they can sail in shallower waters and some can even be sail all the way up onto the beach, called beaching a cat .
• Catamaran: is a boat with twin hulls positioned parallel to each other. This design lends stability to the craft, and since there are two hulls, each can be narrower than a monohull without giving up stability. 
• Monohulls: boats with one hull. They derive their stability from a heavy keel and a wide hull, in comparison to a catamaran with two thin hulls separated far apart.
• Length over all (Loa): is measured from the aft to the bows including all gear such as bowsprits etc. To be compared with Length on waterline LWL.
• Length on waterline (Lwl) is the boats length measured on the surface of the water.

If you want to better understand catamaran construction and the impact of hull shape on performance and safety I suggest you read the book Catamarans; The complete guide for cruisers . It has helped me to better understand multihull dynamics in a more structured way than just googling. Gabo

Different Beam to Length Ratios

Hull centerline beam to waterline length (bcl/lwl) :.

The distance between the centerlines of the hulls divided by the waterline length on one hull is a good indicator of performance. It measures the points of the boat that interacts with the water. A higher ratio will give a higher resistance to capsizing and a lower ratio will increase drag due to wave interactions under the bridge deck.

Compared to the beam overall to length overall (Boa/Loa) that more or less only gives you an understanding of whether or not the boat will fit in a certain slip or what you will pay for a canal passage.

Hull Fineness Ratio (HFR)

Hull Fineness Ratio (HFR) is another name for Hull length-to-beam ratio . This is basically the same as the ratio mentioned above but only measures one of the hulls instead of the entire boat. And “fineness,” essentially, means “thinness.” Most cats have a ratio between 8:8 and 10:1 .

Boat Overall Beam (Boa) to Length Overall (Loa)

These are the exterior measurements of the boat. This ratio will not offer much other information than estimating marina fees and general boat size. To understand catamaran stability the two above ratios are much better since they show how the boat interacts with the water. It is in theory possible to have a very high Boa/Loa ratio but still have a boat that is very unstable due to having a low Bcl/Lwl ratio.

General Rules When Calculating Ratios

Ratios are exercises in long division. Since you remember your rules from math in school, you know that the order of the numbers in the equation makes a difference. 

Make sure you divide Beam by Length (B/L) and not the opposite!

If you mix them up you will get the wrong result and you might assess the stability of the boat incorrectly. And remember to stick to either meter or feet.

The formula looks like this:

B/L = Beam (in ft or meter) to length (in ft or meter) ratio

But how do you measure and from where to where? With those questions in mind, we add even more terminology to all this ciphering.

If, for instance, you have a bowsprit (the railing at the bow that extends past the deck), including this in your length measurement will skew your ratio. The extra length added by the largely cosmetic feature will not contribute to the stability or lack thereof of the craft, mainly because it does not touch the water.

So we look, then, at the measurements at the waterline .

Why Ratios Matters

If your Bcl/Lwl is too low, you will have an unstable craft. Adding a sail to the mix makes it even more so – if you have a ridiculous ratio of something like 1:18, wind in the sails at the correct angle will very likely capsize it. A wave of moderate size could do it, too.

If you want to know why catamarans capsize i suggest you read my other article ! Gabo

But a 1:1 Bcl/Lwl will make for a floating square with the maneuvering ability of a brick. A floating brick, sure, but it’s still a brick. This ratio is something you only see on really fast racing trimarans, since trimarans lift the windward hull the actual ratio when turning is half of that.

The fineness of a hull determines its speed and stability, which means that with every increase to one of those factors comes a decrease in the other. 3:1 seems to be the Goldilocks Zone for most monohulls. But since catamarans have two hulls separated wide apart the cat will be able to have thinner hulls while still maintaining high stability, a ratio around 8-12:1 is common on catamaran cruisers.

Final Thoughts

Casual sailors may never calculate Bcl/Lwl, B/L, or hull fineness ratio. But if you’re looking to buy a boat and want to better understand its sailing capabilities then these numbers will give you the ability to objectively compare different boats.

Speed and stability are the main factors governed by these ratios, and a change in one of them changes the other in the opposite direction. Generally speaking, the wider the beam, the more stable a ship is.

• Boat Building: Catamaran Design Guide – Catamarans Guide
• Marine Link: What Hull Shape Is Best?
• MB Marsh Marine Design: Length-beam ratio
• Multihull Dynamics: Six Kinds of Cats and Two Kinds of Trisi
• Ocean Navigator: Beam and Draft

Owner of CatamaranFreedom.com. A minimalist that has lived in a caravan in Sweden, 35ft Monohull in the Bahamas, and right now in his self-built Van. He just started the next adventure, to circumnavigate the world on a Catamaran!

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