The Rot Doctor


Subject: Severely rotted (window) sills
Date: Sat, 26 Jul 2003

I have been using your products (CPES™ and epoxy filler) for some time in small repairs to my home.

I am now tackling a number of sills, and I have for the most part been replacing the sills and casings, thinking that if the rot went all the way through the wood, it was too far gone for repair.

I'm beginning to get the idea this may not be so. Many sites are instructing that just about anything can be rebuilt with epoxies.

This is true. Epoxies are stronger than wood, by far. It usually comes down to an issue of cost vs. time ... and selecting the right epoxies.

So, a couple of questions before I use up the rest of my stuff and have to reorder:

1. What, in particular, is the advantage to using Layup & Laminating resin™ between CPES™ coats and filler? Are my previous repairs at a disadvantage for not using it ( I don't recall seeing it before, but I could be wrong).

There is no disadvantage at all. It can be a little confusing, I know, but the L&L Resin™ is intended for those areas where an epoxy putty (Fill-It™) cannot be easily applied, where a flowable epoxy is needed, OR, in those instances where the home owner wants to make custom-consistency putty, in which case the L&L Resin™ is mixed with sawdust until the desired consistency is reached. On sills and sashes, the L&L Resin™ is not often used.

2. If repairing a sill, which has rot damage all the way through, should I leave just enough material spanning the "would-be" hole to accept CPES™, and then fill?

Yes. You can leave about as much of the deteriorated wood in place as you wish, assuming it isn't simply falling out. The CPES™ will harden it, and open spaces can be filled with the Fill-It™ Epoxy Filler.

Is it unnecessary to further treat the underside?

CPES™ will easily penetrate through to the underside if the wood is at all deteriorated.

Or, should I clear out the hole if necessary, apply CPES™ the the sides, and then build up the frame somewhat before filling with epoxy (recall that since sills are placed at an angle - 7 or 8 degrees from horizontal I think - there is a gap between the sill the window framing)

I would try and leave wood in place, treat it with the CPES™, and then a few days (or longer) later come back and make the fill with the Fill-It™ Epoxy Filler. It simplifies the process a bit, and the result will be VERY strong.

I guess that's all my questions for now. I look forward to your response, at which time I'll order a couple gallons of stuff I suspect.

Ron G


You're asking all the right questions. Using the epoxies can save you a lot of time, and produce a strong repair that is virtually rot-proof.

Feel free to come back if you have additional questions.