We design many residential additions that have rotted wood sill-plates due primarily to wood-destroying insects. It is so common, that we have developed standardized details to address such conditions. There are many kinds of wood destroying insects; however the one that causes the most damage to residential wood-framed structures in our area is the subterranean termite. Home buyers often overreact after discovering a termite condition and sometimes back away from buying an infested house. The discovery of termites should not be cause for alarm: concern maybe, but certainly not alarm. Termites work very slowly; it may take many years for termites to do serious damage to a house.
Termites can be completely controlled through the application of chemical insecticides. The two chemicals most widely used were chiordane and Dursban TC. However, both chemicals are considered a potential risk to human health and if termites are discovered they should be exterminated professionally. It should be noted that because termites work very slowly, termite proofing your house need not be done immediately upon learning of an active infestation. Take your time and get two or three estimates from reliable termite exterminating firms. Seek out one that provides a guarantee against future reinfestation. There are very few instances where houses are so badly damaged from termites that they are deemed unsafe. Usually the damage is localized and minor in nature and repair or replacement of the infested wood members is not necessary. If you are in doubt of the structural integrity of any of the affected members, you should consult a professional.
Termites in our area play an important role in the natural ecological cycle. They feed on cellulose, the main ingredient in wood, and help to break down dead trees in our wooded areas thereby enriching the soil. In fact, termites usually began attacking houses when the wooded areas are cleared for building construction and there was no other available food in the vicinity of their nests. Even if a house is infested with termites, they usually do not live in the house but are there only to gather food. Albeit; a nest may be in a house adjacent to a constant moisture source such as a leaking pipe. When a colony matures termites leave the nest (swarm) to set up a new colony. These “reproductive” termites sprout wings for the swarm and are abot a half-inch long. They are poor fliers and generally flutter around before falling to the ground. Termites and ants are easily confused. The termite has a thick waste and straight antennae whereas the ant has a narrow waste and bent antennae (see photo above) . Swarming generally occurs in the spring. Swarming in a house is an indication that a colony is nearby. A swarm is short lived and you may not even see it, however, if there was a swarm you can tell by the discarded wings.
Subterranean termites require a dark, damp environment. In their search for food, worker termites build tunnels or tubes that help conserve moisture and shield termites from the light. These tubes may be noted on foundation walls, the outside of wood framing, or even free standing between the ground and an overhead pipe or wooden beam. There even may be current tubes inside the voids of a concrete~block wall that would be impossible to note during an inspection. Commonly, termites enter a house by eating their way through untreated wood members that are in direct contact with the ground. One very vulnerable area is beneath a concrete entrance slab adjacent to wood framing. In some homes a strip of metal, known as a termite shield, is placed between the foundation and the sill plate. In most cases this gives the homeowner a false sense of security and does not prevent an attack but only deters one. An opening at a seam, or a hole as small as 1/32 of an inch is large enough for termites to pass through. To eliminate any possible passageways, the base of any wood siding should be at least six
inches above the soil line. Redwood and cedar siding although resistant to termites should not be considered termite proof.
An inspection for termites should begin with a walk around the outside of the house looking for shelter tubes attached to the foundation walls and piers. Next check out the crawl space or basement once again looking for tunnels on the foundation walls and columns. Observe any cracks or spaces, between double or “sistered” joists. sure there are no pieces of wood stored in the crawl space which can lead to infestation. A section of termite damaged wood will reveal channels or galleries that run parallel with the grain. The channels will not look polished, as they do with carpenter ants. If you are not certain of the cause of the damage, have the wood evaluated by a professional. If there are no accessible inspection areas termite activity will have to be determined by a swarm or exterior inspection. I would recommend an inspection at least every two years.
adapted from “DIDJANO” a free service of Precise Home Inspections (Joel Schachter, PE) , intended to acquaint Realtors and Attorneys with various inspection criteria. If you have any questions please contact Joel at the numbers below. ..InPennsylvania: (570) 775 4217, New York/Conn.: (212) 987 0984 or by Mobile Phone: (917) 279 6725….
P.S.- I refer all my home inspections to Joel….
