Mark Smaalders Yacht Designs

Designs for seaworthy, affordable cruising boats, sail and power
Specializing in wood and wood/epoxy construction

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North Sea 29

Long cabin version of the NS 29. A short cabin version is also available.

LOA (includes bowsprit & rudder)

37’ – 4”

Long. Center of Buoyancy

15.28’ aft


Length on deck

28’ –11”

Center of Gravity

.35’ below DWL



25’ – 4”

Prismatic Coeff.




10’ – 3”

Pounds/inch imm.



Beam at WL

9’ – 2”

Dellenbaugh Angle

13.53 (stiff)

Draft (cb up)

– 8.5”

Wind pressure coeff.

1.30 (stiff)


Draft (cb down)

6’ – 1”

Moment to trim 1”

1022 lbs



13,500 lbs

Wetted surface

232 ft²



4800 lbs

Maximum righting moment

28180 ft lbs at 70 degrees


Ballast/Disp. ratio


Limit of positive stability (hull only)

130 degrees


Sail Area

644 ft²

Tankage (water)

57 gallons


Sail Area / Disp.

16.28 (gaff rig, working sail)


23 gallons


25 gallons

(Weight calculation includes an additional 20 gallons of water or fuel in jerry cans)

Disp. / Length


The North Sea 29 is a centerboard boat, originally designed for sailing in the rough North Sea. She's a substantial boat that should prove a very capable ocean cruiser.

She offers excellent stability and the promise of good performance, while the centerboard will make it easy to escape crowded anchorages or explore shallow cruising grounds. 

Plans for the North Sea 29 include computer generated offsets with no lofting needed. No building molds are used — four laminated ring frames plus bulkheads provide the mold over which the strip planking is fastened. The strips are then covered by two layers of 1/8"/3mm veneer.

A Bermudan rig is available as an option.

A steel ballast box that simplifies the ballast pour is available as an option.  Two boats are under construction, one in the US (Montana) and one in Belgium.

Study plans include a copy of the detailed construction key. Click here for plan prices and ordering information

NS 29 under construction in Montana

NS 29 under construction in Montana

NS 29 under construction in Montana


4-5 berth layout with short cabin trunk and forward head

4 berth layout with long cabin trunk and forward stateroom