Subject: information please
Date: Fri, 05 Mar 1999
My wife and I are still in the "research phase" of building a log home. I am a carpenter by trade, but have no experience with log construction. The preservative & insect prevention aspect of log construction is thoroughly confusing to me. I have read publications that suggest that you mix concoctions in which to soak the logs. At present, the preservative is the only part of construction that has me scared. I read about your product & have a few questions.
* Does CPES have any insect repelling qualities?
Yes, but see discussion below.
* Is CPES all you need to apply to logs for reasonable protection against moisture?
Yes, but see discussion below.
* What is the expected coverage from a gallon of product?
Depending on the absorbency of the wood, between 200-300 sq ft per gallon.
* Should CPES be applied to the entire log before construction or should it be applied after construction is complete?
After construction is complete, unless you see signs of wood deterioration on
the raw logs, in which case you would treat that area prior to construction.
* How often should CPES be reapplied?
As a surface treatment for general protection, every couple of years. For
treatment of rot or deteriorated wood one proper treatment will be all that is needed.
Any information would be appreciated.
Thank you in advance for your assistance,
Jay & Amy
Jay & Amy:
You ask some good questions and are right to be concerned about wood
preservation. This problem gets some log home owners into bigger problems than
they had anticipated.
Rule #1 is keep the water off the logs. Try and design the house so this is
done as much as possible.
Whether the logs should be treated before construction raises a lot of issues.
Much depends on the type and condition of the logs. If they are aged and dry
then they will absorb treatments readily, including CPES. If they are still
somewhat *green* then they won't, because the sap and moisture won't allow
good penetration. This is why we suggest that you wait until the home is
constructed before thinking about the raw wood treatment. The only exception I
would make to this is that all log juncture points be treated with CPES before
assembly. The CPES will soak/coat the wood and give strong resistance against rot in these areas, which are not so easily accessed after construction. Nothing will
protect wood better than a top-grade penetrating epoxy. But epoxies -- all
epoxies -- are expensive, and to treat every bit of every log would cost
thousands of dollars. This is why we suggest treating just the vulnerable
areas first and then keeping good vigilance on the structure as it settles and
ages. Another vulnerable area that can be usefully CPES-treated is the log
juncture lines before the application of chinking. You just brush on the CPES,
give it a few days or so to cure, and then apply chinking. Chinking will stick
just fine to CPES-treated wood.
Soaking raw, dry logs in immersion baths of petroleum preservatives (like
kerosene/wood tar/japan drier) will go a long way toward preserving the wood,
but you'll end up with dark logs and a strong odor. It was done in the old
days when nobody cared. There are modern versions of this kind of formula sold
by log home builders and log home suppliers, and for all I know they are just
fine. The good ones have UV protectants (which are expensive and there must be
enough in the mixture to do some good) and should be used.
But no matter what you do, wood rot will eventually appear sometime,
somewhere. And this is what you attack with the CPES. There is nothing on the
market that penetrates wood like CPES and it's epoxy base assures you that the
treated wood will remain treated indefinitely. If the rotted area is
reasonably dry and the wood is saturated with the CPES nothing more needs to
Insect protection is another issue. Wood that has been soaked in CPES is
highly resistant to insect or bacteria attack, and wood that has been attacked by
insects should be treated with CPES to consolidate the damaged wood and to
make the wood unappealing to the insects. Still, coating the whole house with
CPES will not prevent insect infestation, because there are too many areas
that insects can get at that the CPES will never reach. CPES would help, but
again there is the cost issue. Preventative measures (get the wood off the
ground on stone or concrete foundations, treat the ground around the home with
pesticides if it is a known termite area, etc.) and constant vigilance is the
way to go. Some insects are more annoying than damaging, and those you just
have to fight.
So, the bottom line here is protect what you can at construction time and then
keep a good eye out for rot and deterioration. All log end should be
CPES-soaked after the wood has dried, because they may rot if you don't. The
normal wood preservatives don't work as well because they are petro-based and
the bacteria eventually degrade petroleum mixes. This can never happen with an epoxy.
If you have more questions come back, and we'll be happy to try and answer them.