http://intheboatshed.net/2008/10/15/intheboatshednet-skiff-photos-of-a-model/

Gav

It’s about 10 inches at the design payload of two biggish blokes. That’s fine for a boat like this that has to be rowed and is in any case a largely flat-water boat because of its flat-bottomed form. She’d be fine for rivers and generally sheltered spots (like the Swale!) but that flat bottom with limited rocker (curve fore and aft) would pound mightily on waves.

Some of the design books – notable John Teale’s excellent How to design a boat include graphs that provide suggestions for freeboard, height at ends, beam, displacement, width of stern and so on.

However, they’re very arbitrary and lots of other issues intervene – for example, a small fishing boat’s sheerline needs to be near the water so that the crew can work nets and lines, a boat that is to be powered by oars needs to have a low sheerline to make rowing possible, and a designer working to create a boat from, say, two sheets of ply will have restrictions to work with.

Then there’s the point that upswept bouyant ends are generally more important than freeboard amidships. If the wave’s underneath you, then your bouyancy should keep you dry even with a small-ish freeboard, but a wave that’s coming towards you from bows or particularly stern can easily fill a boat if it fails to rise to meet the hill of water.

This is less of a problem with bouyant ends, which will rise, and with high ends. High ends also bring stability, by the way – those Vikings knew something.

I’d suggest, then, that the Auray punt is a good example of how a small boat can be designed with a low freeboard in the middle, and yet be surprisingly seaworthy for its size.

Gav

Jim