J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment Replace Fiberglass floor or repair?

The answer is yes - the wood is put on top of the finished fiberglass floor. Below the fiberglass in the area is vermiculite which is probably waterlogged and the reason that you see delamination as it freezes and expands.

Here is an interesting writeup from Rich Miller who rebuilt hull #294