I am finishing a downstairs room. The exterior walls are wrapped and sided on the outside, insulated in the wall cavity, and the drywall is pretty well sealed. I am in Wyoming where it gets quite cold.

I can feel a draft around the box (gap to drywall) as well as into the box itself. I think cold air creeps down behind the insulation and finds a low spot to escape. Putting in the fixture and the cover plate helps, but I still would like to minimize cold air seeping in.

Is there an acceptable way to seal the box? I can foam or caulk around the outside of the box. I could also seal the inside with electrician putty (or whatever it is called).

Thanks!

peter030205

You can buy foam gaskets at your local HD or Lowe's. It goes between the box and the cover to prevent drafts.

Edit: Here is a link to find them on the net. 10 cents per.

AM Foam Outlet Gasket [AM55011] - $0.10 : blackEnergy, The Power to Empower

pwd77

Great, thanks for the tip.

Still...any thoughts on using "putty" to seal the box itself?

tkrussell

Energy saving gaskets for outlets and switches have been around for years, back when energy costs were high....(as opposed to now?)

Draft Stoppers - Energy Saving, Draft Stopping Products from AM Conservation Group

EFI's Consumer Division Residential Catalogue | Electrical Air Sealing

These can be found at any hardware store in the insulation dept.

Light fixtures are bit more involved. You would have to drop a fixture to fill the outlet box with insulation. Or if accessible above, cover with blanket insulation. Be aware of any recess fixtures, some want insulation away 3 " from the housing. ICT rated housings can bury completely covered with insulation

pwd77

Excellent information, thank you!

Rather than try to seal the outlet fixture itself (i.e. with child-proof caps), I was thinking of plugging gaps in the back of the box with electrician "putty."

Regarding light fixtures upstairs, I have taken to caulking all of the holes and gaps from the outside so there is no air exchange; I hope this is acceptable. They are then insulated by the blanket insulation in the attic.

labman

If you are over a crawl space or unfinished basement, take your caulking gun down there too. Warm, moist air can follow the pipes to the attic.