While termites do not eat foam insulation, they are able to tunnel through it in order to get to the wood in the structure. A termite infestation inside foam insulation is often not visible to a homeowner or a pest control operator during a pest control inspection, until swarming and severe damage to the wood of a structure has occurred. Foam insulation installed behind stucco makes termite infestations even more difficult to detect. To date, research has been inconclusive regarding the efficacious incorporation of pesticides into foam, during the manufacturing process. By 1992, it was estimated that 50 percent of new buildings use some form of foam insulation.
Foam insulation has excellent thermal qualities, making it a good choice for energy conservation.
In the past, basic termite biology has been ignored in use of these materials below grade. Termites can use the below-grade foam insulation as a pathway into the structure by tunneling through the foam, or between the foam and masonry. Because insulation is hidden from view by aluminum, vinyl siding, wood, paint, stucco, etc. For this reason, any energy savings that foam insulation helps to achieve can be negated by the cost of termite damage to the structure. Waterproofing or coating the foam insulation will not keep termites out.