Genoa

Definition and key measurements

The genoa extends aft of the mast, increasing projected area beyond the foretriangle.

Standard dimensions:

I = forestay height (deck to hounds)

J = foretriangle base (mast to stem)

LP = perpendicular from luff to clew (> 100 %)

Area = (I × J × LP%) ÷ 2

Overlap = (LP – J) ÷ J × 100 %

Genoa categories

#1 light-air genoa

LP 130–155 %

Maximum area for 5–12 kn

5.5–6.5 oz cross-cut Dacron or tri-radial laminate

Foam luff pad for reefed shape

Optimal pointing 32–35° AWA

#2 medium genoa

LP 110–130 %

All-purpose sail for 12–20 kn

6.5–7.5 oz Dacron or hydranet radial

Moderate draft; balanced helm

Standard inventory sail on 30–45 ft boats

#3 heavy-weather genoa

LP 100–115 % (barely overlapping)

Built for 20–30 kn; replaces furled #1

8–9 oz Dacron or spectra/Dacron grid

Reinforced clew and tack; heavy UV strip

Often used partially furled on roller

Roller-reefing genoa

Single sail covering 5–30 kn via furling

LP 135–145 % with foam luff and vertical battens

6.5–8 oz cross-cut Dacron

Shape retention to 50 % furled

UV strip on both leech and foot

Selection criteria

1. Measure I and J from rig plan.
2. Match LP to typical conditions:
   • Light-air lake → 145 % #1
   • Coastal mixed → 135 % roller-reefing
   • Offshore → 120 % #2 + #3
3. Furling vs hanks: convenience vs durability.
4. Cloth: laminate for racing, Dacron for cruising longevity.

Maintenance protocol

• Rinse with fresh water after every sail.
• Flake or roll carefully; avoid foot creases.
• UV strip facing sun when furled.
• Inspect foam luff, telltales and leech line monthly.
• Re-stitch UV strip every 3–4 years.

End-of-life upcycling

When draft aft exceeds 20 % or UV strip fails, retire the genoa. Resail repurposes the large panels into:

• 50 L waterproof duffels with original sail numbers
• Boom tents and spray dodgers
• Cockpit enclosures (10,000 mm HH)
• Reversible sun awnings

Each genoa diverted = 12–18 m² of premium sailcloth reused.

Procurement and upcycling

Send I and J measurements to info@resail.org for a matched second-hand genoa or to schedule free collection of your retired sail. Every exchange keeps 15 m² of high-performance cloth in circulation