Design
Core Sound 20 Mark 3
Designed by Graham Byrnes
A 20 ft shallow-draft cruiser and racer for two by Graham Byrnes of B&B Yacht Designs, developed from the Core Sound 20 with events like the Everglades Challenge in mind. Stitch and glue plywood, 800 to 875 lb, 180 sq ft of free-standing cat ketch sail, 430 lb of water ballast, a weighted centerboard, tabernacle masts, a large flush-deck cabin and a self-draining cockpit. It draws 9 in with the board up. Plans and a comprehensive CNC kit are offered, backed by a how-to video series.
B&B itself calls this a complicated boat and designed it around CNC-cut parts that carry their own layout marks, which removes most measuring. Some building experience helps. Budget 1,000 to 1,800 hours as a rule of thumb. Measured medians from build logs appear below.
What building a Core Sound 20 Mark 3 actually takes
Medians from the build logs kept on this site, not the designer’s estimate. Nobody has logged this boat here yet, so they are empty until the first builder does.
Those medians firm up as more people log this boat.
Builds of this boat
Nobody has logged a Core Sound 20 Mark 3 here yet.
If you are building one, yours becomes the reference: the page the next person building this boat finds when they search for it. One photo and one line is a valid first entry.
Start the first log of this boatBoats like this one
Same type, closest in length.
| Design | Plans from | LOA | Logs |
|---|---|---|---|
| Core Sound 20 | B&B Yacht Designs | 20′ 0″ (6.1 m) | 0 |
| Saltaspiaggia | Modern Wooden Boat | 6.1 m (20′ 0″) | 0 |
| Marsh Wren 20 | Devlin | 20′ 2″ (6.15 m) | 0 |
| Idea 19 | Modern Wooden Boat | 6 m (19′ 8″) | 0 |
| Vagabond Plus 20 | Bateau | 19′ 8″ (5.99 m) | 0 |
| Haiku 700 | Modern Wooden Boat | 6.2 m (20′ 4″) | 0 |