From time to time we hear the question asked: What’s the difference between monohull and multihull sailboats anyway? Aside from the obvious difference in the number of hulls, there are several very real ways in which monohull and multihull sailboats provide unique sailing experiences. As the makers of trimarans in particular, we here at WindRider admit we may be a littlebiased – but let us show you why, to us, multihulls win every time.
Stability
Because of the stability having two or more hulls creates, catamarans and trimarans are noticeably more level than comparable monohulls when sailing. Even when powered up, multihull sailboats will rarely heel more than 5-10 degrees before it’s time to reef, compared to monohulls which can often reach up to 20+ degrees at high speeds. For a more relaxing and comfortable sail in terms of stability, multihulls win out over monohulls easily.
An added benefit of multihulls gaining their stability from the beam and hulls is that there is no need for ballast or a substantial keel – so exploring shallow waters that may be off-limits to monohulls is no problem for a cat or tri. You can even pull your multihull right up onto that perfect beach if you want with very little difficulty – try that with a monohull and, well, good luck.
Speed/Performance
If speed is what you’re looking for, monohulls have nothing on multihulls. Cruising catamarans are typically 25-30% faster than a cruising monohull of the same length, while trimarans can regularly double monohull sailing speeds on nearly any point of sail. Of course, these comparisons change a fair amount when the boats are loaded for cruising. Monohulls are much less affected by load than catamarans and trimarans and can maintain much of their performance when loaded for cruising, whereas multihulls are much more sensitive to load and experience reduced speeds when weighed down.
The speed of multihulls also serves as a valuable safety feature. With decent weather information, it’s relatively easy in a cat or tri to simply sail around rough weather to avoid it altogether. A slower monohull may have a bit more trouble doing the same.
Safety
Though it’s true that any boat – mono or multihull – can capsize in rough enough conditions, the fact is that it’s much more difficult to flip a catamaran or trimaran than it is to flip any monohull. It takes very high winds, too much sail, and large breaking waves to flip a modern cruising cat or tri. Large ballasted monohulls are not only easier to capsize, but once they have, they’re much more likely to end up on the bottom of the sea with the crew bobbing in the water. When you compare this to a cat or tri that is much more likely to stay afloat as a big liferaft and spotting target (whether upright or not), there’s no question of which situation you’d rather be in.
Living Space
As far as living aboard goes, catamarans and trimarans vary a bit more than on other subjects. Catamarans, with their two widely-spaced hulls, are ideal live-aboard crafts as they typically have space below equivalent to a monohull 10+ feet larger. When combined with added cockpit space, possibly a flybridge, and more than doubling the deck space, it becomes a whole different ball game. Trimarans, on the other hand, generally have a bit less space below when compared to monohulls of the same length. Though they do provide additional storage in the amas and added net space that may make up for some of the small size, the fact is that trimarans are always going to have smaller living spaces than monohulls of the same length, and catamarans reign supreme in this category by a long shot.