The Rot Doctor


Subject: CCA and CPES
Date: Tue, 11 Jan 2000

Thank you for the quick response.

I do have a quick pair of questions for you that I didn't see among those posted in the Q&A sections on your website:

1. Any experience with CPES on pressure-treated (CCA) wood? CCA lumber is notorious for being difficult to paint, and I thought that a quick 1-coat application of CPES might improve the (latex) paintability of CCA wood.

As long as the wood isn't oily/greasy to the touch, the CPES will bond to the CCA wood and will greatly improve the latex paint bond.

2. Another CPES question: During the application of CPES on wood trim/sills with traces of latex paint still present, I noticed that the CPES caused the remaining latex paint to bubble--is this bubbling going to create adhesion problems with new paint applied over these surfaces?

Yes, on thinner paint layers it will act as a paint remover. I generally remove at least 95% of the old paint. If the paint chips are small enough, the CPES will get into the wood behind the paint, and after curing you could knock off any loose chips and the wood underneath will be treated and ready for paint. If you knock or sand off a larger chip and the wood is bare underneath, spot treat it with CPES.


Thanks! Feel free to post for others to benefit.