Plywood boat plans. if you are looking for a way to build an inexpensive boat you should definitely consider plywood boat plans. using plywood is one of the best ways. Download our flat bottom boat design for the extreme flats 20, a light weight, quiet hull with low freeboard. buy flats boat plans and more at bateau.com!. New plywood “quick canoe” plan builds in as little as 4.5 hours (or a couple of weekends).