During the early twentieth century, building code regulations were introduced in order to make structures as safe as possible for human occupants. By the mid 1990s, the International Code Council published the first edition of the International Building Code manual, which was promptly adopted by most US states, including Massachusetts. Included in this manual are numerous mandatory construction practices that aim to better protect structures from termite infestations. For example, one of the earliest termite damage-prevention laws to be introduced requires builders to keep all of a home’s structural and cosmetic wood sources from making ground contact, as doing so prevents soil-dwelling subterranean termites from gaining direct access to a home’s timber frame. Massachusetts residents are also legally obligated to obtain a permit to construct additions onto an existing home, and this includes decks, patios and balconies.
Surprisingly, around half of all decks in the US are not code compliant, and most decks have either sustained termite damage or are vulnerable to termite infestations.
According to Dr. Michael Potter, an urban entomologist, improperly built dirt-filled decks, raised wooden steps, and other raised attachments are responsible for a significant percentage of subterranean termite infestations that occur in homes. Piers and other types of deck supports must be separated from the external walls of a home by at least 2 inches in order to prevent termites from gaining hidden access into a home through foundation cracks. The wooden steps and wooden support beams attached to decks should be raised at least 6 inches above the ground surface by concrete slabs or blocks. Ideally, a deck should be situated above a concrete slab rather than dirt, and an access space should be incorporated into the deck’s construction to allow pest control professionals to inspect for termites. If removing dirt from below a deck is not possible, then the dirt-filled deck should be raised at least 6 inches above the ground surface and the soil should be heavily treated with termiticides. The area below a dirt-filled deck should be well ventilated, as an abundance of vegetation around the deck’s perimeter will contribute to moisture buildup, causing the lumber components to become saturated with moisture over time, and therefore, vulnerable to attack by moisture-loving subterranean termites.
Do you have a dirt-filled deck on your property?