I am confused here Ski38off. Divinycell is a modern core material. How did you use it for a floor and stringers? Divinycell is made of "foam" but comes in squares on a fabric background which is meant to be encased in glass. I suppose I could fold it over to make stringers and use libral amounts of resin but they would not be nearly as strong as wood stringers... To make a floor out of Divinycell you would have to glass multiple layers on both sides so why not just use Coosa board and just glass the top side?