Insulating Drafty Outlets

A cover-plate foam gasket can reduce air leaking around an outlet on an exterior wall. It cannot fix every leak inside a wall, and it does not repair an unsafe outlet.

Before you start

Use a gasket made for your outlet or switch type, a screwdriver, and a plug-in lamp. If the outlet is scorched, loose, buzzing, or unusually hot, stop using it and call an electrician.

Fit the gasket

1. Turn off the relevant circuit at the breaker. Verify the plugged-in lamp goes out; keep the circuit off while working. A lamp check is not permission to handle wiring.
2. Remove only the decorative cover plate. Do not remove the outlet, electrical box, or panel cover, and do not touch terminals or wires.
3. Fit the purpose-made gasket as its package directs. It should lie flat without obstructing the receptacle openings.
4. Refit the plate without overtightening. Restore power once the plate is secure.

Check the result

On a windy day, compare the draft by holding a tissue near the plate. Keep it out of the socket. If air still leaks, ask an energy assessor or electrician about sealing around the box. Do not spray expanding foam into the electrical box or stuff insulation around wiring.

For a wider review, follow the electrical safety checklist.

Sources and scope

• DOE: air sealing and outlet gaskets
• CPSC: home wiring hazards

These references support the guidance above. Source review is not a hands-on test of your home or a certification of a product. Follow the instructions for your exact model and local requirements.