Brick On Brick

Q: When doing termite treatments we frequently come across a condition in crawl spaces where we are not certain if our treatment is adequate. Typically, the house will have a brick stem wall and brick piers. The problem occurs when one of the brick piers is built right next to the brick stem wall. We can treat three sides of the brick pier but it is treating the side touching the stem wall that causes us some concern. How best can we treat this area? (S.T.)

A: This is not an uncommon condition. In some cases, I believe these piers are installed post-construction during repair work or to give further support to the flooring. In any case, they do create a problem for PCOs in treatment.

Obviously, you would treat the brick pier by drilling to the center and treating according to label directions. The three sides of the pier that are exposed can be trenched and treated in a conventional manner. Take note of how deep the footing is and whether or not it is continuous with the footing for the stem wall. If the footing is continuous with the stem wall footing then you may not have as big of a problem as you thought. However, the area between the pier and the stem wall must be treated. One option is to drill into the joint between these two features from the exterior through the stem wall. I would drill through the mortar joints in at least two locations along the interface with the pier. Injection of termiticide can be accomplished using equipment such as the B&G Ban-Drip Void Injector. If there is sufficient space between the pier and the stem wall, you may be able to treat this joint from within the crawl space. Make sure you apply the product from both sides of the pier where it joins the stem wall. It is also important to make certain that your emulsion thoroughly treats the joint at and below grade. Also, don’t fail to indicate on your treatment graph the location of each of these structural features.

This will be important when it comes time to perform your annual reinspection. These areas will have to be inspected closely.

Jeffrey Tucker is president of Entomology Associates, Houston. Questions can be sent to Tucker at P.O. Box 70375, Houston, TX 77270, or faxed to 713/681-9069.