The decision of what size catamaran to buy is an important one, and also a surprisingly difficult one. The best size catamaran will depend a lot on your needs for the boat – how you plan to use it, how many people you’ll typically have onboard, and what your expectations are for boating liveaboard life.
A larger boat will be more spacious and comfortable for living onboard, capable of comfortably housing more people, but has higher costs for purchase and maintenance – and a larger catamaran can also require more skill (or crew) to safely sail. Choosing what size catamaran to look for is the first key step in your purchasing process because it will narrow down the field of options, and can have a big impact on how happy you end up with your decision.
The biggest factor that typically comes into play is cost – the larger the catamaran, the more it will cost to purchase and maintain. The increase in cost from increased boat length comes from many sources:
- Higher purchase price due to the larger boat and more complex systems
- Moorage (long-term or transient) is typically priced per foot
- Maintenance costs are often priced per foot (haul-out, bottom paint, etc)
- Fuel costs will be higher when motoring
- Larger boats usually have greater electrical system needs, which means more expensive power generation requirements (larger batteries and power generation systems).
Even just increasing in length by 2 feet or 5 feet can make a significant difference in costs. In some areas of the world, marina slips aren’t available in odd sizes, and the marina may charge for the total slip length even if your boat is shorter than that. So in a marina that has 40’ and 45’ slips, increasing in boat length from 40’ to 42’ will have the same moorage costs as a 45’ boat.
Many people say to buy the biggest boat you can afford. But it’s also easy to underestimate the maintenance costs involved, and the more money you spend on the purchase, the less you’ll have for a cruising budget. So another oft stated advice is to buy the smallest boat you can be happy living on.
Catamarans in the 35-40’ size range will typically include 2 or 3 berths, for up to 4 people to live onboard comfortably, or perhaps 6 for shorter durations. As you move up into the 40-50’ range that may increase to 3 or 4 berths, with one of them being a large master suite holding a queen sized bed. Larger catamarans are likely to have greater bridgedeck clearance, so if you’re tall that may be a consideration for the under 40’ boats. Families with children may want to consider a catamaran with more staterooms while a cruising couple can get by with fewer.
Bigger catamarans will have more storage for things like extra sails, water toys (inflatable paddleboard, kayaks, scuba gear) and provisions. They’re likely to have a larger galley for meal prep and more entertaining space where you can easily host large groups of friends. Generally they’ll have more heads as well, which provides redundancy if one head clogs or breaks (and more privacy when hosting guests) but additional maintenance work.
They’ll also have larger tankage (fuel, water, holding) which helps accommodate the larger crew expected with a larger catamaran, or if sailing as a couple, helps extend the time you can go between ports.
The longer the boat, the faster it sails, in general. The maximum speed of the boat is related to the waterline length, and larger catamarans will have longer waterlines. So one consideration in choosing a catamaran size is whether you have a need for speed and faster passages. However, many factors can affect performance, such as the weight and design of the catamaran, so if performance is important you may be better served by focusing on models known for their sailing performance.
As catamaran size increases above 45’, the loads on the rig and control lines can be quite high, so you may find you need additional crew (or electric assist devices like electric winches) at those sizes. As a boat’s sail area increases, the force on the sails tends to increase exponentially – so a boat that is seemingly only slightly larger (50’ vs 45’) can actually have substantially higher loads, which means more work when it comes time to reef in a squall.
Most performance catamarans will have faster downwind speeds than a monohull, so if sailing performance is important to you it would be a good idea to check how well the catamaran points when going upwind (how close to the wind it can sail).
Finding the Catamaran Size Sweet Point
If there’s a sweet point to choosing a catamaran size, it would probably be around 40 feet. 40-feet is where the breakpoint begins where the salon gets small and it doesn’t have as much galley space as one would hope for – and 50 feet gets kind of big to the point where you might need a 3rd crew member.
The best size for you will depend a lot on your needs – how many people you plan to have onboard, how far you plan to cruise, and how much space you’re used to on previous boats or land homes. For the typical couple cruising the Caribbean or Mediterrean, around 40’ will probably provide the best bang for the buck in terms of affordable options while ensuring spacious living accommodations.
With larger catamarans it can be difficult to find a marina with moorage available that fits the boat, so if your plan depends on moorage in a particular area it would be good to check what’s available in the size range you’re considering.
Ultimately the right catamaran will depend on your plans and needs – if you intend to sail around the world, your requirements will be very different from cruising the ICW or vacation cruising for 2 or 3 weeks a year. Start by honestly assessing your goals and then determining the size range that best meets those needs, considering the trade-offs between size of vessel, cost and ease of handling with your typical crew size.