10/09/2026
Most pest problems on a home's exterior start at the roofline.
Wasps and yellow jackets build under eaves and overhangs. Spiders colonize the corners where the soffit meets the fascia. Overwintering insects (stink bugs, box elder bugs, cluster flies) pack into the gaps in that zone to wait out the cold. By the time you see them inside in October, they've been up there since September.
An exterior eave treatment covers the underside of the soffit, the fascia board, the overhang perimeter, and any penetrations in that zone. The Pacific Northwest has active wasp and spider pressure from spring through fall, and the high points of a structure are where that pressure lands first.
spmwa.com