In termite-prone areas, rigid foam insulation should not be used on the exterior of the foundations below grade because they can provide a pathway for infestation. Termite detection systems  discourage termites and allow for inspection. This includes adherence to local codes that require at least a six-inch gap between rigid foam exterior wall insulation and the ground, and at least a four-inch gap between the top of the rigid foam insulation or other wall systems and the top of the foundation wall. This strip of bare wall can be painted white to make inspections easier. Lastly, flashing is provided at the sill plate to help block and expose termite migration.