The Rot Doctor


Subject: Motorhome delamination
Date: Thu, 23 Sep 1999

Ran into your web site today and found your CPES product very interesting. I have several questions, but will start with this one. I am currently looking at a motorhome that is for sale, but has some delamination between the fiberglass outer skin and the material that the fiberglass skin was laminated too - could be very thin wood or styrofoam. The delamination was caused by water leaking in at a roof seam. This seems to be a typical problem on motorhomes because the great majority are built with flat roofs - in some ways they seem they are designed to leak.

You're right about that!

My question is can CPES be used to relaminate the skin back to side wall? I would propose to drill small holes in the fiberglass skin and then introduce the CPES in sufficient quantities to assure that both surfaces are coated and then apply some form of pressure to force the skin back against the side wall. I would think that it would be well to work in small increments - maybe two square feet at a time, working from the bottom of the motorhome upwards toward the roof. Since CPES is apparently has a thin viscosity - it would seem to me that it would easily flow down from the injection points and have a much greater chance of covering the area to be bonded than the thicker more viscous epoxy products I have seen. Sorry for the length of the question, but choosing the wrong product usually makes for more work than finding the right product to start with. Hope you can respond and am looking forward to hearing from you.
Rodney W.


Okay, to a certain extent the CPES will work, but you have to bear in mind that it is VERY thin and designed to penetrate wood. If the skin backing material is wood or anything porous then the CPES will penetrate that more than it will act as an adhesive.

This is not all bad. The CPES will eliminate any potential rot problems and protect the backing material (if it's a foam TEST FIRST -- CPES will dissolve some foams!). What you would need to do is follow the CPES (after about a week and it has had time to cure) with our honey-thick Layup & Laminating Resin. This is a highly specialized 1:1 mix resin that needs to sit "in the pot" for 10-15 minutes to thin out, and then can be injected (via a kitchen baster) into gaps or holes. It has a long set-time, which allows it to move to bonding areas normal epoxy resins will not have time to reach. It also retains a degree of flexibility most other epoxy resins do not. So, your plan is a sound one as long as you use both products.

Hope this has been helpful. These products are fairly expensive, as are all premium epoxies, and my guess would be you would be using $300.00 - $500.00 worth of product to make this repair. Come back if you have additional questions.