Be sure to use silicone caulking designed for outdoor use to seal all around the box. Place the gasket and install the cover on top. Turn the power on after you've put the indoor socket back together. Electrical enclosures protect sensitive equipment like wiring, circuits, and control systems from harsh environments. Whether in a factory. In this video we cover the best way to seal the back side of your exterior facing electrical boxes in a new construction custom home. These boxes often go unsealed leading to air infiltration into the wall cavity.