There is floatation and then there is self rescue. I don't think that ready self rescue which is achievable only really by self bailing and serious floatation is expected. If you can get your boat to centerboard trunk level you are doing pretty well. Float boat, crew, gear and something in the bank would be the least you could expect. Most traditional plank built boats with out ballast are there.
That said, Annapolis Sailboat Supply imports the British buoyancy bags that come in a variety of sizes and can get under places. As an example I have sausages of varying sizes fitted under the side seats of my Harrier running from the stern to where the seats go away. There are strap bands on these and I have run ( laced ) a line under the seats at the seat stringer onto which these are strapped as there was nothing on the hull surface, a disadvantage of plywood. Then I have a canoe triangular bag under the foredeck. Harrier being a 1/4 inch ply boat, it would float the crew with it being pretty much awash. The bags take it so that the trunk is out of the water and it could get bailed.
If you are carrying gear and your rig a net or otherwise lash drybags into place you will also have floataion.
On a warm summer day take your boat to a pond and fill it up. It better to do it when its fun.
Last edited by Ben Fuller; 07-17-2007 at 06:44 AM.
Reason: adding information
Ran Tan, Liten Kuhling, Vernon Langille, Josef W., Merry Mouth, Imp, Macavity and a quiver of unamed 'yaks.
"Bound fast is boatless man."