Prior to the mid 20th century, houses and buildings were constructed in a manner that left them vulnerable to insect pest invasions, and this is why older structures see the highest rate of extensive infestations today. After the second World War, the pest control industry bloomed, and in an effort to reduce costly insect pest issues, housing authorities enacted regulations requiring homes to be built with insect-resistant structural features. For example, in order to reduce subterranean termite infestations, structural lumber and wood siding could no longer make contact with the ground soil. Although these regulations dramatically decreased urban and suburban insect pest infestation rates, modern homes remain prone to developing moisture issues, which attract a vast number of insect pests indoors.

Most modern homes contain hollow walls, or “wall voids,” that provide insect pests with an indoor refuge. There exists numerous indoor and outdoor entry points that provide insect pests with easy access into wall voids, including crawl spaces, foundation cracks, attic spaces, and gaps surrounding utility pipes and cables that enter homes from the outside. Rainwater, condensation from pipes, plumbing leaks, and water from bathtubs cause moisture to develop within wall voids, which creates ideal conditions for a majority of household insect pests, most notably cockroaches, termites, and numerous ant species.

Moisture in wall voids may lead to the growth of fungi, which serves as a food source for several insect pest species. In the northeast, insect pests such as stink bugs, Asian lady beetles, western conifer seed bugs, and boxelder bugs nestle into exterior cracks and crevices beneath siding and shingles, which lead directly to interior wall voids. These insects, along with cluster flies, also enter attic vents where wall voids are easily accessible to the pests. Termites, ants, bees and wasps also establish nests within wall voids, and in some cases, pest control professionals are not always able to eradicate heavy infestations in wall voids without removing drywall and insulation. Regularly inspecting a home for plumbing issues, rainwater leaks, gutter obstructions, and preventing rainwater from pooling around the foundation, can save a home from becoming a haven for moisture-loving insect pests.

Have you ever discovered that your home’s wall voids had become infested with insect pests? If so, did the infestation start as a result of a plumbing leak?