The Rot Doctor


Subject: Dry Rot Repair (stringer)
Date: Thu, 22 Mar 2007

Dear Doc,

I have a 32 ft. Carver boat with some dry rot in one area of the engine compartment where a stringer meets the bulkhead. There is a hole about the size of a silver dollar in the fiberglass. When I poke in it with a long screwdriver I can feel the dry rot. When I tap the affected area of the stringer, it gives a thud instead of a firm, solid sound. I believe the dry rot extends about 8 inches on each side of the hole and about 7" deep. Everywhere else I tap on the bulkhead and stringers seems solid.

I would appreciate your suggestions for making repairs. The area of dry rot seems somewhat void, as the rotted wood has settled. Should I fill the area with sawdust or something else before making repairs?

Any advice will be very greatly appreciated.

Thank you,
Jack W.


Do this:

1) Using your tapping method, determine the extent of the deteriorated area, and then drill a 1/4" hole at about 5" intervals along the top of stringers.

2) When the wood is reasonably dry (slightly moist is okay), saturate the wood with our CPES (Clear Penetrating Epoxy Sealer). Allow the area to absorb all the CPES that it will. CPES will end the rot problem, harden soft wood, and form the bonding base for the others resins.

3) Wait for at least a week.

4) Pour our Layup & Laminating Resin into each hole, about 1/3 cup into each hole. The L&L Resin is very slow-setting and will gradually settle down into the wood, consolidating it into a very hard structure.

5) Wait for about 48 hours (or longer) and then fill to the top by pumping in a slurry mix of the L&L Resin and sawdust. This can be poured in or pumped into the holes with our re-usable caulking tubes.

That's it...rot-proof and very strong.

It's hard to know exactly how much material you will need, but I would guess the 2-quart unit of the CPES will be enough of that product, and I guess I'd start with two of the 2-quart units of the L&L Resin and see how it goes...hard to know because you can't see volume to be filled. Sawdust, tubes etc you can get if needed.

Feel free to come back if you have additional questions.