Designed by Jim Brown


Searunner Trimarans were designed by Jim Brown and are offered in 5 sizes; from a folding, trailerable 25-footer up to the 40-footer. They are sophisticated plywood vessels, sheathed with fiberglass and epoxy. These boats are well-known in cruising circles and have been built in many countries around the world. All of them feature central cockpits, centerboards, walk-through main bulkheads, and cutter rigs to distinguish them from other designers’ work. Their slightly compound-curved plywood-sheet topsides and clipper bows give these boats a distinctive look.

When designed in the 1960s, Searunner trimarans were a step ahead of other designs in the simplicity of their construction and the high quality of their plans. Since then, we have made improvements and updated the plans to include new methods and materials. All plans feature detailed working drawings of all parts, and full-sized patterns for all frames and bulkheads. The original Searunner Construction book, out of print for many years, is now available as a free download here.

The series starts with the Searunner 25, which is a trailerable, coastal cruiser. This design accommodates two persons in a very compact interior. The next size up is the Searunner 31, available in either demountable A-frame or fixed wing configuration. Both of these configurations have accommodations for up to four persons and are capable of offshore passages. The A-frame version is designed for highway transport under 8 feet wide, whereas the fixed wing version has more useable deck area. Next up the line is the Searunner 34, a true offshore design with accommodations for up to 5 persons. It is available in full-wing and vented-wing versions. The Searunner 37, has berths for up to 8 persons in 2 cabins. This is a popular, extended cruising design. Top of the line is the Searunner 40, with a similar interior to the 37 but greater payload capacity.


Jim Brown's letter to Searunner Owners

The following is the reprinted introduction from the Searunner Catalog, written and printed by Jim Brown in 1975.


Dear Reader,

Multihulls are developmental boats. For many of us, this development is very attractive because it allows us to really make a difference in our boats, and in our lives as sailors. I believe that Searunner trimarans exemplify this difference. Their development has stabilized, and their accomplishments suggest that they are worthy of your consideration for serious ocean cruising—especially if you intend to build your own boat.

Selecting a design is no simple process because much of the analysis is obscure. You must try to weigh such factors as: the skills required of the builder compared to the end resultant quality and appearance; and the designer’s choice of materials and construction method as relates to known performance and longevity of his boats. You must appraise the cost of the finished boat as it relates to value received and value resold; and examine the sea-keeping qualities and forgiveness aspects of the real boat in the real ocean. Think of the safety and performance of your vehicle, and the on-the-go comfort of your home, all at once.

This is a complex analysis, I admit, and weighing-out quantities against qualities tends to blind us from the basic quest … which is to find a boat we like! A serious sailor must appreciate his boat on an aesthetic, emotional level or else the two of them will never be safe and happy together. This is a very personal choice you are making.

Let me tell you of my own appraisal of Searunners. First of all, these boats satisfy me personally. Of course my opinion is biased because I designed the Searunners. But second, it appears that they also satisfy the diverse requirements mentioned above, and for lots of other people besides myself. There are more than a thousand of us who have chosen to build our own boats from among the five Searunner sizes, and there are probably two-to-three hundred of us who have completed our project and moved into the realm of ocean cruising. It is widely agreed among us that our boats meet the real cruising needs.

>Three main factors explain Searunner acceptance: design, safety, and service. The first one—design—I was involved in myself, but safety and service were largely brought about by other people. All of yacht design is said to be a compromise, and yet the current trend is toward great divergence between racing and cruising; between super speed and super comfort.

I am against the divergence. Experience has taught me that a cruising boat must be good for something besides just going fast, and besides just living aboard. If it is really used for ocean travel, it needs to have performance and accommodations in about equal measure. The real virtue of the multihull is that, if it is well designed, it can provide more of both in the same boat.

Relative to other multihulls, or to any other sailing boats of comparable size, I believe that Searunners combine more of these two prime features—very good performance for an easily-handled cruising multihull, and very comfortable “seamanlike” accommodations for that performance.

I feel secure in my attempt to match real requirements with real boats because I am one of few designers who has subjected himself to his own treatment. I have built from my own plans and cruised extensively in my own boat. Together with my wife and sons—four of us in a thirty-one foot windship—have traveled for several years [in a Searunner 31], on two oceans, and mostly under sail alone—for we have just a 4-hp outboard auxiliary.

Of this experience we can say for sure that real full-time family cruising isn’t easy, but it’s good … if you’ve got a good boat. Whatever kind it is, it had better be capable of making progress to windward under strong trade-wind conditions, be easy to reef and steer in a blow, be a good ghoster in the calms, be maneuverable in a crowded harbor—all of this with a reasonable payload and without dependence on an engine. In her cabins, she needs to be commodious and functional, especially while under way, without reliance on a bunch of sophisticated gadgetry. Those are the real requirements.

In our cruising we have never come across another boat that was used for this purpose and that could out-sail our SCRIMSHAW, and that had such livable accommodations in the same length [of just 31’], and that I could have built myself for anything like the same price. That is where Searunners fit in, right in the convergence of those diverse requirements. If those are your requirements then it is my firmly held opinion that a Searunner design will meet your needs.

Surely the boats themselves are not altogether responsible. Searunner sailors have earned this remarkable record by careful building and good seamanship. Nonetheless, when compared with any other sailors, in any other boats, for any other fifteen-year period, and any other several hundred thousand sea miles, I think we can conclude that Searunners are safe boats. A certain factor for luck must be considered, but no amount of controversy can distort long-term results in the full-size test tank!  Are there any other boats of any type with such a safety record?

Regardless of your eventual choice of a design I wish you good luck in your search, and good cruising in your boat. Thank you for considering a Searunner.

Jim Brown (1975)



25 31 34 37 40
Length overall 25'0″ 31'2″ 34'4″ 37'4″ 40'10″
Waterline length 23'1″ 28'1″ 31'7″ 34'4″ 37'3″
Beam of main hull under the wing 3'9″ 5'0″ 5'5″ 5'10″ 6'2″
Extreme beam, outside the rubrails 16'7″ 18'8″ 20'11″ 22'3″ 23'11″
Draft, hull only 1'4″ 1'11″ 2'4″ 2'1″ 2'4″
Draft, centerboard down 4'6″ 5'9″ 6'5″ 6'4″ 6'9″
Displacement, full load (in lbs.) 2,500 7,000 9,000 11,000 13,800
Displacement, dry 2,000 5,500 7,000 8,500 10,000
Payload 500 1,500 2,000 2,500 3,800
Sail area, main 122 195 215 268 336
Sail area, max (main and genoa) 332 552 646 760 948
Mast length from trunk 28'0″ 35'0″ 43'6″ 45'0″ 50'0″
Bridge clearance 32'3″ 41'0″ 45'3″ 48'6″ 54'0″
Engine, maximum horsepower 5 OB 20 25 30 40
Engine, standard tankage (gallons) 10 25 40 45 60
Standard water tankage (gallons) 10 25 40 45 60
Cruising speed under power (knots) 5 6 7 7 8
Crew, min-max 1-2 1-4 1-4 1-5 1-6
Berths, min-max 0-2 2-4 2-6 2-8 2-9
Headroom 4'1″ 6'4″ 6'4″ 6'4″ 6'4″
Study Plans (2015) $20 $20 $20 $20 $20
Design Fee (2015) $600 $800 $900 $1,000 $1,200
Shipping in USA (2015) $10 $10 $10 $10 $10
Shipping International (2015) $15 $15 $15 $15 $15