Rot Doctor

[Miscellaneous Q&A Index]

Subject: RV Rot (Trim Screw Rot Repair)

Date: Monday, December 28, 2020


I have done repairs on 2 Class C’s and currently own a Class A.

I replace all outside trim screws with Stainless Steel.

I have found some rot areas where the side trim screws attach. Sometimes a longer, larger screw will bite but I’d rather inject an epoxy to repair properly. I have some large syringes used to repair delaminated walls that I can use or some curved dental syringes.

I would like to inject your CPES to flood the area, then fill with epoxy.

What procedure would you recommend?



I would first inject S-1 Sealer, (CPES is unavailable) making sure the wood is dry. Inject enough to saturate the wood. This could take as much as a week to dry.

My guess is that you are screwing into plywood. If so, then moisture can cause delamination before rot. So you may have some delamination going on. If so, getting an epoxy resin into the delaminated areas would be the cure for that. Once this was done, then the wood should be firm enough to screw in to. Keep in mind that the epoxy resin, when it is only a day or two old, will not be nearly as strong, so screws could pull out at that point. Sometimes it is better to glue in a wood dowel to give the screw something to compress, rather than just epoxy to fill the hole.

Lastly, the solvents in the S-1 Sealer don’t play nice with styrofoam insulation. So if there is any near your screw holes, you will want to be careful about getting the S-1 on any styrofoam.


[Miscellaneous Q&A Index]

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