Back to Search
Seaforth 24
Designer: Stephen Seaton  ·  Builder: Capson Marine/Precision Boat Works (Usa)  ·  First built: 1977
+ Add to Compare
About the Seaforth 24

Designed by Stephen Seaton and launched in 1977, this compact cruiser represents classic late-1970s sailboat design philosophy with its traditional long keel and transom-hung rudder configuration. Built by Capson Marine and later Precision Boat Works, the Seaforth 24 offers surprising accommodation and seaworthiness in a trailerable package. The boat's substantial displacement of 4,200 pounds and generous ballast-to-displacement ratio create impressive stability for coastal cruising and weekend adventures. Her long keel design provides excellent directional stability and predictable handling characteristics, though at the expense of quick tacking performance. The masthead sloop rig with 208 square feet of sail area delivers adequate power while remaining manageable for small crews. With a comfort ratio of 23.92, the Seaforth 24 leans toward the comfortable end of the spectrum, making her well-suited for relaxed coastal cruising rather than spirited daysailing. Her capsize screening value of 1.82 indicates good initial stability and resistance to knockdown. The hull's theoretical speed of 5.52 knots reflects her cruising-oriented nature rather than racing pedigree. This fiberglass design appeals to sailors seeking traditional sailing characteristics and coastal cruising capability in an affordable, transportable package ideal for exploring protected waters and nearby anchorages.

Core Dimensions
LOA (Length Overall) 24.00 ft / 7.32 m
LWL (Waterline Length) 17.00 ft / 5.18 m
Beam 7.33 ft / 2.23 m
Max Draft 2.50 ft / 0.76 m
Displacement 4,200.00 lb / 1,905 kg
Ballast 1,600.00 lb / 726 kg
Sail Area (Reported) 208.00 ft² / 19.32 m²
Design & Construction
Hull Type Long keel w/trans. hung rudder
Rigging Type Masthead Sloop
Construction FG
Designer Stephen Seaton
Builder Capson Marine/Precision Boat Works (USA)
First Built 1977
Owner Reviews

No owner reviews yet — be the first to share your experience with this boat.

Performance Ratios
SA/Displacement Sail Area to Displacement ratio measures how much sail power a boat has relative to its weight. Higher values mean more performance and speed.
Under 14 — Heavy cruiser, slow14–18 — Cruising sailboat18–22 — Cruiser/racerOver 22 — Performance racer
12.82
Ballast/Displacement Ballast to Displacement ratio shows what percentage of the boat's total weight is ballast. Higher values generally mean better initial stability and stiffer sail carrying.
30–35% — Typical cruiser35–45% — Stiff performance boatOver 45% — Racing oriented
38.1
Displacement/Length Displacement to Length ratio measures how heavy a boat is relative to its waterline length. Lower values mean a lighter, faster boat.
Under 100 — Ultralight racer100–200 — Light cruiser/racer200–300 — Moderate cruiser300–400 — Heavy cruiserOver 400 — Very heavy
381.64
Comfort Ratio Ted Brewer's Comfort Ratio predicts how comfortable a boat will feel in offshore conditions. Higher values mean a steadier, more comfortable motion in a seaway.
Under 20 — Uncomfortably rough20–30 — Acceptable coastal30–40 — Good offshore comfortOver 40 — Very comfortable offshore
23.92
Capsize Screening Formula The USHS Capsize Screening Formula estimates offshore capsize risk. Lower is safer — values under 2.0 are considered acceptable for offshore sailing.
Under 2.0 — Safe for offshore2.0–2.2 — Borderline offshoreOver 2.2 — Coastal use recommended
1.82
Hull Speed Hull Speed is the theoretical maximum speed of a displacement hull, calculated from waterline length. Most cruising sailboats reach this speed in moderate conditions. 5.52 kn
S# (Speed Number) The Speed Number (S#) is a quick performance index. Higher values indicate a faster, more powerful design relative to its size.
Under 3.0 — Slow cruiser3.0–5.0 — Average cruiser5.0–7.0 — Performance cruiserOver 7.0 — Racer
0.98
Pounds/Inch Immersion Pounds per Inch Immersion (PPI) tells you how much weight is needed to sink the boat one inch. Useful for calculating how additional gear and stores affect waterline. 445.25 pounds/inch
SA/Displacement (Calc) Calculated Sail Area to Displacement ratio using actual measured sail dimensions rather than reported values. More precise than the reported SA/Disp figure. 12.84
Rig Dimensions
I (Foretriangle Height) 24.50 ft / 7.47 m
J (Foretriangle Base) 7.50 ft / 2.29 m
P (Mainsail Luff) 21.82 ft / 6.65 m
E (Mainsail Foot) 10.67 ft / 3.25 m
SA Fore 91.88 ft² / 8.54 m²
SA Main 116.41 ft² / 10.81 m²
SA Total (100%) 208.29 ft² / 19.35 m²
Est. Forestay Length 25.62 ft / 7.81 m
Engine & Accommodations
Engine Make Renault
Engine Model RC8D
Engine Type Diesel
How It Compares

vs. Cal 2 24, Neptune 24 Fk, San Juan 24

This boat Similar boats
Dimensions
LOA
Seaforth 24 ★
24.0 ft
Cal 2 24
24.0 ft
Neptune 24 Fk
24.0 ft
San Juan 24
24.0 ft
LWL
Seaforth 24 ★
17.0 ft
Cal 2 24
19.2 ft
Neptune 24 Fk
21.0 ft
San Juan 24
19.5 ft
Beam
Seaforth 24 ★
7.3 ft
Cal 2 24
7.8 ft
Neptune 24 Fk
8.0 ft
San Juan 24
8.0 ft
Displacement
Seaforth 24 ★
4 lbs
Cal 2 24
3 lbs
Neptune 24 Fk
3 lbs
San Juan 24
3 lbs
Ballast
Seaforth 24 ★
1 lbs
Cal 2 24
1 lbs
Neptune 24 Fk
1 lbs
San Juan 24
1 lbs
Sail Area
Seaforth 24 ★
208 sq ft
Cal 2 24
271 sq ft
Neptune 24 Fk
250 sq ft
San Juan 24
246 sq ft
Performance
PHRF Rating (lower = faster)
Seaforth 24 ★
Cal 2 24
Neptune 24 Fk
222 s/nm
San Juan 24
222 s/nm
SA / Displacement (higher = more powerful)
Seaforth 24 ★
12.8
Cal 2 24
18.2
Neptune 24 Fk
18.5
San Juan 24
18.2
Ballast / Disp (higher = stiffer)
Seaforth 24 ★
38.1 %
Cal 2 24
37.8 %
Neptune 24 Fk
San Juan 24
51.6 %
Comfort Ratio (higher = more comfortable offshore)
Seaforth 24 ★
23.9
Cal 2 24
18.1
Neptune 24 Fk
14.2
San Juan 24
14.9
Capsize Screening (lower = safer)
Seaforth 24 ★
1.82
Cal 2 24
2.01
Neptune 24 Fk
2.17
San Juan 24
2.17
Displacement / Length (lower = lighter)
Seaforth 24 ★
381
Cal 2 24
234
Neptune 24 Fk
San Juan 24
192
Hull Speed
Seaforth 24 ★
5.5 kts
Cal 2 24
5.9 kts
Neptune 24 Fk
6.1 kts
San Juan 24
5.9 kts
Speed Number (higher = faster)
Seaforth 24 ★
1.0
Cal 2 24
2.4
Neptune 24 Fk
3.3
San Juan 24
2.9
Find a Seaforth 24 For Sale