Shellback wrote:Right, I have removed them. I was wondering about what's behind the fiberglass, is there a wood backing? The screws that were holding my boards in place didn't appear to be be bedded in anything substantial, and I'm thinking if something was there it's probably rotted away.
The technical term for the wood there is "carlin" (a good term if you want to search older posts).
The wood apparently is not treated and not really enclosed, which makes it subject to dry rot.
Depending on the severity your options include total removal and replacement, or you might get away with using a product like System Three's RotFix. It's a very thin epoxy that you can apply via syringe to all the screw holes (and if you feel like it, you can drill a few small holes in additional locations). It soaks into the wood and if it's not too far gone, will reinforce what's there. Once it's cured, you can inject thickened epoxy into the holes just prior to reinserting the screws (after waxing them). That will allow the epoxy to fill all gaps and in fact create "threads" while leaving the waxed screws removable.
Removal appears a manageable project, because the wood isn't fully encased (there's just a bit of fiberglass cloth draped over it on mine). I would recommend that you coat any replacement with epoxy on all 6 sides and that you do not bother with laminate (You will want to seal all screw holes as above with the thickened epoxy). The tricky part is that these are not in a straight line and you may need to work at to get your new wood to follow the curves.
Haven't done either repair myself - while some spots show signs of rot, they haven't progressed to structural, as my screws generally still hold, so I've put that repair off for the long term. I did have to upsize them in a few places.