Termites swarmers reoccurred for five years, even after repeated treatments with liquid termiticides. The swarmers consistently emerged along the back wall particularly around the rear door frame and a bay window in the kitchen.
An inspection was made in the basement along the band board under the area of activity. While the band board was heavily damaged, there were no live termites. Closer inspection of the siding immediately adjacent to the brick patio, which abutted the back of the house for twenty feet in the area of infestation, revealed that there was foam insulation running behind the brick and the concrete slab underneath.
Three courses of brick were removed, and the foam insulation behind the brick was exposed. As the insulation was removed, thousands of worker termites were observed to be feeding on the exterior surface of the band board. The insultation extended down behind the concrete slab under the brick. All of the insulation was removed, and the exposed gap and band board were saturated with a termiticide. It was recommended that an asphalt-based expansion material be used prior to replacing the brick and that the brick patio be sealed on a regular basis to prevent water absorption.