Hello – I have signs of the powderpost beetles in the interior walls of my home. My pest control company says they can't treat it because the wood is stained and it won't absorb the pesticide. The area is a window sill in a house that's over 50 years old. I did a remodel in 2005 and have just noticed the problem. What would you suggest I do?
Thanks in advance.
They are right in that the best treatment for this problem cannot penetrate over a stained surface. This means it won't be possible to treat from inside the room over the finish you see or from above, down over the treated sill. But there is usually "two sides" to any story…
In this case, the "other side" would be the bottom side of the sill as seen from inside the wall void. In the space below the window, the wood inside this void is generally not painted or stained. This space can be made accessible by drilling holes through the window sill down, as well as through the wall and into the wall void under the sill. Be careful and space the holes in between the studs of the structure (this is usually 16 inches) and once you've got the entire area made accessible via these entry holes, you should be able to do an adequate application.
As explained in our POWDERPOST BEETLE CONTROL ARTICLE, the product BORACARE will penetrate wood when applied to rough, unfinished surfaces. Using a FOAMING TOOL, you can pump the Boracare and Foam through the holes you've drilled and inject the product throughout the void. I recommend doing this at least twice (before sealing the holes) to insure you get good coverage. Since Boracare will normally penetrate several inches, you should be able to properly protect the wood using this "other side" technique. If you have further questions, please give our office a call at 1.800.877.7290.