The Rot Doctor


Subject: Window frame rot
Date: Mon, 27 May 2002

You stated: "You can test the depth of the sponginess with a sharp knife point, pushing it in until you hit firmer wood. If the depth is less than an inch, a generous surface application of the CPES will do the job of sterilizing the wood and hardening it with epoxy resin. If the depth is much deeper than an inch, you will have to think about drilling downward-sloping holes at the upper portion, which will allow the CPES to slowly filter down into the soft wood."

I am amazed that the CPES will penetrate from the surface of the wood to a depth of one inch.

Does the wood suck it in like a sponge?

Yes, that's exactly what happens. Mixed CPES is about the consistency of diesel fuel.

How do you apply it ?

With a natural bristle (disposable) brush or a coarse spray.

How do you know when it is sufficiently saturated?

When the product is no longer absorbed and begins to pool on the surface. This happens quickly, within minutes.

What is the drying time and do you come back with several coats?

Surface cure time varies between a couple of hours to a day, depending on the temperature, air movement, type of wood, etc etc. Deep penetration can take several days to cure, or even longer in really deep penetration such as logs.

Whether multiple coats are required depends on the degree of wood deterioration. Usually mildly soft wood will cure hard with a single CPES application. On more seriously deteriorated wood, a second application may be required. On really bad wood, we recommend that after the CPES application, you come back with our Layup & Laminating Resin, which is thicker and very slow setting and settles into the wood for a complete, structurally solid repair.

The rot appears to be going up the brick type molding for the first inch or two from the miter joint ends. If it is deeper than one inch at these joints can I use a needle to get the material in?

Yes. We would suggest that if what you describe is the case, you drill some small, downward-sloping holes at the top edge and inject the CPES until the holes/wood will absorb no more, or you see it start to run out further down. The holes can be closed later with our Fill-It Epoxy filler, or, if they are really small, a dab of paint.

How much material do I need? I have several joints to repair.

I would probably order the 2-quart unit, although the 2-pint unit might be enough. It's hard to know in advance, since everything depends on the wood absorbency. Unmixed CPES has a virtually unlimited shelf life, if kept in the capped cans and away from prolonged freezing.

Thanks again for your response.

You're welcome, and feel free to come back if you have additional questions.