Subject: Another Log House
Date: Wed, 05 Aug 1998
I have read your responses to queries about log rot and insect damage repairs. I have the same problem in my log home and would like some clarification. The epoxy/wood flour mixture you refer to-can you explain what specifically you mean?
It is a mixture to putty consistency of our Layup & Laminating Resin and
wood flour or sawdust. In the case of a log home, sawdust would be just
fine and cheaper than buying wood flour (note: wood flour is very fine sawdust from finish-sanding wood). Our L&L Resin has a longer pot
life and cure time than the normal petroleum-based epoxies, which is why
it is desireable for this application.
Is this the material that will show on the outside of the logs after they are treated with CPES?
It can, if it is used to close drill holes, fill cracks, etc. An epoxy
filler is always to be desired, since it will bond with the epoxy
impregnated wood. You could even add dye to try to get close to a color
match. Once hard, it is VERY difficult to sand smooth, and it will not
take exterior stains in the same way wood will. An alternative to
closing the drill holes with the resin/sawdust, is wood bungs that have
been coated with the CPES. The CPES will protect them from rot.
If people have hollow logs, we always recommend that they saw away the
face of the log, treat the interior, fill it, and then replace the
treated face-piece. It keeps the natural look.
And what about concrete? I like that idea, but again what will that look like on the outside of the logs?
We are ambivalent about concrete. People have reported using it to fill
logs, because it is inexpensive. Its drawback is that it tends to
attract moisture, but on the other hand the wood around it is
CPES-impregnated and will never rot. It is also commonly used in old
wood boat bilges without bad effect. Our boat, in fact, has about 1/2
ton of it in the stern.
The people who use it put it under the face piece, so the concrete isn't
visible.
The way I understand it, I need to:
1. Drill and treat logs with CPES
Yes. However, the drill-and-inject method assumes that most of the
interior wood is still there, even though rotten. This then becomes the
"framework" for the CPES, which infuses it and then hardens. You can
tell what's going on in the log when you drill. As long as you keep
pulling wood, okay (it should be reasonably dry), but if you hit large
gaps then you need to think about fillers and if the gaps are large,
sawing the face off the log.
2. Fill large gaps with epoxy/woodflour (or concrete) mixture?
Right.
3. Finish with UV protectant/waterproofer
Right.
Thanks for your help.
You have the basic procedure down correctly. I hope my notes above are
of some help. As far as we know, the CPES is the only product available
that will truly penetrate and harden large masses of bad wood, and work
its way to the bad-wood/good-wood interface, which is where the rot
fungi are.
Let us know if we can be of further help.
Doc