Bellingham Wa. Home Inspection (King of the House): Slower Than A Speeding Bullet

Well, here is a crawl space decimated by anobiid beetles. This pest works slowly, over the years, but when it has taken a hold -- BROTHER! Again, as always, it was a conventional crawl space and intended by design to have open crawl space vents. The primary conducive condition was vents that have been blocked for probably about 20 plus years. In this region of the country, this infraction of blocking the vents often leads to anobiid infestation. In fact, in the latest Washington State Department of Agriculture Structural Pest Inspector Manual, the scientists and entomologists from the WSDA and Washington State University consider blocked or impeded/inadequate crawl space vents as one of the most serious conducive conditions an inspector can find. That includes their criticism of louvered vents that minimize air flow and faulty vents that lead to ventilation "dead spots which keep a crawl space from properly drying out". They state that inadequately vented areas, especially corners, will lead to an excessive moisture condition that will most likely attract wood destroying organisms. Anymore, when I arrive at an older home and the vents are blocked, or the vents are below grade, I figure about an 85% chance that there will be anobiid damage in the crawl space. So far, I have not been wrong very often. This is a very serious pest problem. This crawl space shown had the following issues: Every post was damaged, every beam was damaged, every joist was damaged, the sill plate was powder, the sub-floor was largely dust, the rim joist was very damaged. If you wonder what this wood is like structurally, it is weak -- it is like Styrofoam or even balsa and easy to pull it apart. If anobiid is caught in time, it can sometimes be resolved without major replacement of the wood.

Realtors, if you are in the PNW, and you are listing, or working with a buyer, and the crawl space vents are blocked -- be wary and realize that there might be wood destroying organism damage to such a degree that it could be an obstacle to a quick closing. In the photos below, the white powder, around all the visible holes in structural members is recent frass, sawdust and fecal droppings from the insect. This frass indicates an ongoing infestation. That evidence was supported by high moisture readings and the overall clammy feel of the crawl space. Such an infestation will keep going infinitum, until the nutrition in the wood is all gone (eaten) or the conducive conditions are eliminated --  providing some ventilation, such as allowing air flow under this house. Obviously, at this home significant amounts of the wood must be replaced, even if the anobiid is controlled. Much of the wood is merely a shell on the outside.

Damaged joist, anobiid has now moved into the sistered member too

 Damaged Beam

Post and beam

Sill plate and rim joist damage

Sub-floor damage

Thanks for coming by

Steven L. Smith

Bellingham Wa. home inspector

www.kingofthehouse.com