The Rot Doctor


Subject: Floor replacement runabout
Date: Monday, January 20, 2003

Hi, I came across your site looking for info on how to replace my floor in my boat. I have 1975 Glastron 14' runabout. The floor is pretty soft just about everywhere. I have a 65 Merc on it that runs great and the rest of the boat is great condition. I bought it last spring for $800 with the trailer. I would like to fix the floor but I have no idea where to start. I am a carpenter by trade so the work should not be a problem. Someone told me to just go over it with 1/2" plywood, but somehow that doesn't sound right. Can you help or point me in the right direction.

Thanks Rob

Mostly what is under the floor is empty space, probably filled with foam. In certain areas there are stringers. These stiffen the bottom and support the floor to reduce flexing. In some areas there may be a fuel tank. As you don't want to damage anything, I would set a circular saw to just at or under the thickness of the floor and cut out a section. Removing this will let you look into the interior and see where you can safely cut through without damaging anything below. Carefully cut away any bad wood.

If you get near the sides or stern or any other vertical member, leave between 2" and 4" of the old wood, unless it is so bad that if just crumbles away. Even if it is pretty bad it can be re-strengthened with our products and used to fasten a backing plate to the underside. This plate will form a lip to attach the new section to.

Cut the replacement piece, treat the whole thing with a coat of CPES. Put a bead of 3M™ 4200 where the new piece will meet the stringers, and put some Layup & Laminating Resin on both the new piece and the backing plate. Lay the new piece in place and weight or screw it down.

Coat the top with a skim coat of Layup & Laminating Resin, then paint or carpet and you are done.

Let me know if you have further questions.