Short answer: Begin with the rig designer’s intended sail plan. If an overlapping genoa is supported, specify it around shroud clearance, wide sheeting geometry and high righting-moment loads—not monohull assumptions.
Buying a genoa for a catamaran starts with a written brief, not a material label. Use the same dimensions, sailing program and inclusions for every quote so price differences represent real choices rather than missing details.
Useful terms: crossover, draft and LP.
Define the sail’s exact job
A catamaran sails quickly into its own apparent wind, so the useful angle range of a headsail can be narrower than buyers expect. Decide whether the missing performance is close-hauled drive, reaching power or simple manoeuvring. A Code Zero or screecher may solve a reaching gap more cleanly than increasing jib overlap.
List the conditions in which the existing sail works, the point where it becomes difficult and the result you want to change. Include typical crew numbers, annual sailing, storage and whether delivery, racing or offshore use is expected. These details affect design load, finishing and handling choices.
Shape, area and measurements
Measure forestay length, foretriangle, track or self-tacker geometry, mast rotation limits and all shroud contact points. Wide beam changes sheet angles and barber-hauler requirements. On a self-tacking system, the clew board and traveller geometry are central structural and trim decisions, not minor hardware options.
Do not order from a model name or an old sail’s edge lengths alone. Rig tune, rake, replacement spars and deck hardware can change fit. A loft should either measure the boat or give a documented measurement protocol with responsibility for checking every number before cutting.
Cloth and construction
High righting moment can load cloth and corners heavily even on cruising cats. Ask how fibre direction, patch layout and leech control reflect those loads. UV exposure is significant because furling headsails may remain rigged year-round; protective covers and thread should be specified with the same care as the body cloth.
Request manufacturer, product code, nominal weight and panel layout in writing. Ask what is included at corners, reefs, spreader patches and hardware interfaces. The useful comparison is shape retention and service life for your sailing—not “premium” versus “standard” marketing language.
Handling, reefing and hardware
Confirm furler working load, torsional requirements, halyard lock or swivel geometry and bowsprit limitations. A short-handed crew needs a sail that furls consistently and can be controlled from a safe position. Document safe deployment angles and maximum wind rather than relying on trial and error.
Hardware should be named by type and size, with any owner-supplied components listed. Confirm how the sail is hoisted, changed, furled, reefed, dropped and stored. Where loads are uncertain, involve a qualified rigger before ordering rather than treating the sail as an isolated component.
Ask the designer for a simple inventory crossover chart showing jib, genoa or screecher, Code Zero and asymmetric coverage. The chart exposes costly overlap before the sails are built.
Quote checklist
- Original rig and sail-plan limits
- Forestay, track and self-tacker geometry
- Expected sheet, tack and halyard loads
- Apparent-wind range and inventory crossover
- Furler or continuous-line system specification
- UV cover, chafe points and safe operating limits
Also compare GST, freight, measurement, fitting, commissioning, adjustment, warranty exclusions and lead time. Keep the accepted drawing and specification with the invoice so future service or replacement does not begin from zero.
Frequently asked questions
Can every catamaran carry an overlapping genoa?
No. Shrouds, mast position, spreaders, coachroof and sheeting geometry may prevent useful overlap. Confirm the design with the boat builder, rigger and sailmaker.
Is a screecher the same as a genoa?
Terminology varies, but a screecher is generally a larger furling reaching sail flown from a forward tack point. Its structure, furler and safe range can differ materially from a forestay headsail.
Why are catamaran sail loads high?
Wide beam and high righting moment resist heel, allowing the rig to retain more load. Sail and hardware specifications must reflect the actual platform rather than length alone.
Reviewed 20 September 2026. General educational information only; verify boat-specific loads and dimensions with qualified professionals.