Carpenter ants nest in both moist and dry wood, but prefer wood which is moist. Consequently, the nests are more likely to be found in wood dampened by water leaks, such as around sinks, bathtubs, poorly sealed windows/ door frames, roof leaks and poorly flashed chimneys. Nests are especially common in moist, hollow spaces such as the wall void behind a dishwasher, or in a hollow porch column and in dead and rotted spaces in older trees. Since there often will be no external signs of damage, probing the wood with a screwdriver helps reveal the excavated galleries. Another technique for locating hidden nests is to tap along baseboards and other wood surfaces with the blunt end of a screwdriver, listening for the hollow sound of damaged wood. If a nest is nearby, carpenter ants often will respond by making a " rustling" sound within the nest, similar to the crinkling of cellophane.
Carpenter ants may establish nests in a number of different locations. It is important to realize that these locations can be either inside or outside the structure. Carpenter ants actually construct two different kinds of nests: parent colonies which, when mature, contain an egg-laying queen, brood and 2000 or more worker ants, and satellite colonies which may have large numbers of worker ants but no queen, eggs or young larvae. The carpenter ants inside a home may have originated from the parent colony or from one or more satellite nests. For example, the ants may be coming from the parent nest located outdoors in a tree stump, landscape timber or woodpile, or from one or more satellite nests hidden behind a wall in the kitchen or bathroom, or perhaps from wood dampened by a roof leak in the attic. The extent and potential damage to a home depends on how many nests are actually present within the structure, and how long the infestation has been active. Although large carpenter ant colonies are capable of causing structural damage, the damage is not normally as serious as that from termites. In some cases, the damage may be relatively insignificant, but this can only be determined by locating and exposing the nest area.