One of the most effective things I’ve done in the name of trying to conserve energy and make my older home more efficient is seal the outlets on the outside walls with spray foam insulation.
These are the reasons a latex foam was chosen over the polyurethane type.
- There were too many warnings on the polyurethane spray foams about their flash point being 250° F when cured.
- The latex one didn’t mention any such thing when it was cured.
Latex Spray Foam Insulation
WARNING: When insulating an electrical outlet box make sure the power is off to that outlet until the foam insulation has cured. Follow all manufacturer’s instructions.
Doing the outlets that are on an exterior wall will provide the most impact. The outlet shown had some gaps as large as 1/4″ around it. I felt the cold air freely flowing through the outlet box by just putting my hand in front of it.
Gaps Around An Electrical Outlet Box
With the electricity off, the expanding foam was applied.
Spraying Expanding Foam
This is how I applied the foam:
- from the bottom to the top
- for each side done foam was applied from the back to the front
- foam was purposefully allowed to expand over-filling the cracks in the front
Electrical Outlet Box With Foam
A finger was used to smooth the foam around the outlet box.
Once the foam has cured, the power was turned back on.