This is not an unusual issue with older SMs. In Martinique Amel has a person who specializes in the repair. He cuts out the old floor and drops in a new perfectly fitting new one. It is a quick and (I am told) not expensive procedure. For those whose floors are still good, opening the front water tight compartment door whenever the boat is left for some time, will delay or prevent the issue. I also spray the wood floor with an anti-mold solution every year or so and the floors are solid after 19 years.
Good luck,
Miles
S/Y Ladybug, SM 216 now in Port du Marin, Martinique
