What is underneath teak sole aft of galley?

[Wayne]

I have blistered finish appearing on the cabin sole just outboard of the base of the companionway ladder on the stbd side.  2006 Mk II.  What is under the plywood?  A yard is telling me that the wood in this area is screwed and maybe glued in place directly on the fiberglass liner (in other words, is overlaying a sheet of fiberglass).  Is this true?  I had assumed that there were stringers and some space under there.
Thanks in advance for any responses!
Wayne

[Clay Greene]

It was just fiberglass on our Mark I boat.  And the sole panels were just screwed down, no glue.  I would unscrew your panel and take a look at the back side.  My guess is that your problem is water on the top of the panel rather than the bottom but it is an easy thing to check.