If you have an insect problem in your foam insulation, removing them can be difficult. Insects don't eat foam insulation, they tunnel into it. These tunnels lower the insulation properties of the foam insulation. Most foam insulation is coated with borate to prevent insects from infesting it. Removing pests from you home may take a number of months. Removal techniques involve poisons, and may harm small pets or children. In some cases removal of the insulation and starting over from the beginning may be the best alternative.
Step 1 – Prevention
If you are going to install the foam insulation it is best to install the foam over the inside of the basement walls instead of installing it on the outside of the wall. Interior installed insulation prevents bugs and insects from finding the insulation to tunnel through. You may have to install a fire-barrier over the insulation if your building codes require that. This may cost more to install than the installation on the exterior, but in the long run this is the most energy efficient method, and over time will save you the most in monthly energy costs. Another important insect prevention technique is to eliminate moisture within the walls or around the perimeter of the home. Replace any moisture damaged wood before insulation is applied. Move any wood or piles of debris like leave piles from close to the building as these will attract insects that may find their way into your home. Trim branches that may overhang close to windows in your building. Be certain to seal any window eaves and door thresholds.
Step 2 – Pest Elimination
If you have determined that you have a pest problem in your insulation there are a few methods available to remove them. Some are more dangerous than others and may require professional help. The first thing you want to do is try to locate an insect nest. Nests are often concealed and hard to find. You may have to call in an exterminator to locate the nests. If you cannot locate the nests apply an insect dust through the electrical outlet panels. If you can locate the nest, apply the insecticide to the nest. Spray insecticides work best in these situations. Once the colony has been disturbed, they will take action to try to relocate, so multiple applications may be necessary until the problem is eliminated. If you cannot locate the nests, and spraying is not working, insect bait traps may be the next best alternative. Bait traps work by combining a food source with a poison. A slow acting poison will allow the insect to track back to the nest and possibly share the poison with other insects in the nest. A boric acid type of poison is available and should be mixed with a sugar based product as bait. The key to using bait is to locate them in the right location, and to monitor the bait trap activity. If there is no action near the bait trap, move it to a better location. Do not use an insecticide near the bait trap as that will keep the insects away from the trap. The problem you have is a difficult one to cure and will take some time to remove, perhaps months. If you need a quicker response to the problem, it might be best to call in a professional exterminator.