Irish Class 20 Information, Review, Specs

Sailing Performance & Handling

The Irish Class 20 is frequently noted for its "stiff" sailing characteristics, a result of its significant lead ballast—roughly 550 pounds—situated low in the hull. This ballast-to-displacement ratio of approximately 36% provides a higher degree of secondary stability than many contemporary trailer sailers of the same era. While it lacks the raw acceleration of modern sportboats, the Class 20 tracks well and handles gusty conditions with more composure than lighter, unballasted dinghies.

With a Sail Area/Displacement (SA/D) ratio in the range of 22, the boat is surprisingly lively in moderate breezes. Owners often report that the boat finds its rhythm in 10 to 15 knots of wind, where its moderate displacement helps it punch through a typical coastal chop rather than bouncing over it. The swing-keel design, while excellent for reaching shallow anchorages, requires attention to the winch and cable system to ensure the foil is properly seated to prevent "clunking" or vibration at higher speeds. When the keel is up, the boat draws only about 6 inches, making it an ideal candidate for beaching or exploring tidal estuaries.

Interior Comfort & Variations

Despite its 20-foot footprint, the Irish Class 20 features an interior layout designed for weekend cruising rather than just afternoon outings. The cabin typically provides four berths: a V-berth forward and two quarter berths that extend aft under the cockpit seats. For a vessel of this vintage, the use of a full interior fiberglass liner was a mark of quality, simplifying maintenance and providing a cleaner aesthetic than exposed raw fiberglass.

The "Class 20" nomenclature occasionally refers to the standard cruiser, but a more spartan "Daysailer" variant was also produced with a larger cockpit and a truncated cabin. In the cruising version, the cabin often includes a small area for a portable head under the V-berth and a compact galley countertop. The use of teak trim and bulkheads was common in earlier models, though later production runs shifted toward more synthetic materials for ease of care. A larger sibling, the Irish 24, was built on a similar design philosophy, offering standing headroom and a dedicated enclosed head, which remains a popular step-up for Class 20 owners.

Known Issues & Buyer’s Checklist

When inspecting an Irish Class 20 on the secondary market, the primary concern is the integrity of the swing-keel assembly. Over decades, the galvanized pivot bolt and the stainless steel lifting cable can suffer from electrolysis and wear; a failure here can result in the keel jamming or, in extreme cases, departing the hull. Prospective buyers should inspect the keel trunk for stress cracks and ensure the lifting mechanism operates smoothly under load.

Deck delamination is another common "gotcha" for boats of this era. The balsa or plywood core used in the deck construction can soften if deck hardware—such as stanchion bases or cleats—was not properly bedded or re-sealed over time. A thorough "tap test" with a phenolic hammer around the chainplates and mast step is recommended to identify any dead thuds indicating core rot. Finally, check the transom for any flexing or spiderweb cracking, especially if the boat has been fitted with a heavy long-shaft outboard motor exceeding the original manufacturer's recommended horsepower.

The Verdict

The Irish Class 20 remains a respected choice for the budget-conscious sailor who wants a trailerable boat that doesn't feel like a toy on the water.

Pros

• Stability: High ballast-to-displacement ratio makes for a very forgiving and "stiff" ride in its class.
• Versatility: The shallow draft with the keel up allows for easy trailering and exploration of thin water.
• Construction: Better-than-average build quality for the era, including a full interior liner.

Cons

• Weight: At approximately 1,500 pounds, it requires a more substantial towing vehicle than lighter 20-footers.
• Maintenance: The swing-keel mechanism requires periodic underwater inspection and hardware replacement.
• Light Air: The boat can feel somewhat sluggish in very light winds compared to modern, lighter-displacement designs.