IW IW-31 Sailboat Review, Specs, and Listings
Builder drawing- Hull Type
- Monohull · fin
- Rig
- Masthead Sloop
- LOA
- 30.33' · 9.24 m
- Disp.
- 7,800 lbs · 3,538 kg
- First year
- 1968
The IW-31 stands as a quintessential example of a classic cruiser-racer, renowned for its robust construction, balanced performance, and comfortable accommodations. Designed by the esteemed American naval architecture firm Sparkman & Stephens (specifically design #1899C), this 30-foot vessel was brought to life by the Swedish builder IW-Varvet, located on the boat-building island of Orust. With approximately 350 hulls produced between 1968 and 1985, the IW-31 carved out a significant niche as a popular "Half Tonner" and remains a highly sought-after classic within the sailing community today.
Measurements
Dimensions 01
- Length Overall
- 30.33 ft
- Length on deck
- —
- Waterline Length
- 22 ft
- Beam
- 8.83 ft
- Draft
- 5.42 ft
- Maximum Headroom
- —
- Air Draft
- —
Construction & hull 02
- Construction
- Fiberglass
- Hull Type
- Monohull
- Keel Type
- Fin
- Rudder
- 1× Skeg-Hung
- Ballast
- 3,400 lbs (Iron)
- Displacement
- 7,800 lbs
- Water Capacity
- —
- Fuel Capacity
- —
Rig & sails 03
- Rigging Type
- Masthead Sloop
- Mainsail luff
- 31.5 ft
- Mainsail foot
- 9.35 ft
- Foretriangle height
- 36.74 ft
- Foretriangle base
- 11.42 ft
- Forestay Length (estimated)
- 38.47 ft
- Sail Area
- 357 sqft
Calculations 04
- Sail Area to Displacement Ratio
- 14.52
- Ballast to Displacement Ratio
- 43.59
- Displacement to Length Ratio
- 327.02
- Comfort Ratio
- 27.03
- Capsize Screening Ratio
- 1.78
- Hull Speed
- 6.29 kn