The Rot Doctor


Subject: Trailer or camper
Date: Thu, 08 Aug 2002

Can your products be used on plywood sheathed truck cap or tear drop trailer instead of expensive aluminum outer skin? Joe N.


Yes, absolutely, and with an expectation of a longer wood life than you would get with the metal skin. Plastic or metal skins over plywood actually promote wood rot and deterioration. The reason is that the skins condense moisture inside, wet the wood, and then prevent it from evaporating away into the atmosphere. When the sun hits the skin the inside temperature rises and it becomes in effect an incubator for the rot fungi. This is why plywood and structural rot is so prevalent in campers and motor homes.

The proper procedure is to cut and trim all your plywood (use untreated plywood, standard exterior grade) to fit, and then before installation coat it on all sides with CPES (Clear Penetrating Epoxy Sealer). Pay particular attention to the cut edges. Any holes drilled into the plywood for screws/bolts should also be CPES-treated before the fastener is installed.

Final coatings on the ply can be anything from a standard paint to something totally waterproof and UV resistant, such as our Elasta-Tuff™ 6000-AL-HS Polyurethane Coating. The Elasta-Tuff™ 6000-AL-HS is totally waterproof, bonds VERY well to the treated ply surface, and has a life expectancy of 10++ years.

Come on back if you have additional questions.