Best way to insulate a outlet


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Old 01-12-18, 02:34 PM
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Best way to insulate a outlet

We have had some cold days in our area and I noticed some significant drafts coming from outlets on outside walls. What is the best way to insulate the outlets? I see there are some insulating sealers (foam pads) that you can put behind the cover plate, but I'm not sure that will be sufficient in some of our cases. I also see that you can use fireblock insulating foam which seems more involved, but may have a better result. Any thoughts?
 
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Old 01-12-18, 03:48 PM
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Has the basement or crawl space, and attic ever been air sealed?
How old is this house?
Old homes used balloon wall constrution and the walls where open from the basement to the attic.
Rim joist been insulated!
 
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Old 01-12-18, 04:25 PM
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An approach I have used and recommended is to cut out as needed the shape of the switch or receptacle from a piece of contact paper. Size the paper to fit behind the cover plate or in some cases an inch or so around the outside. I found it helped with the kids finger prints and you can select matching colors or contrasting.

But the contact paper will cover the electrical box and the gap between the box and the drywall.

One advantage of the foam gaskets is you use the foam cut-out and a child safety plug to seal the outlet itself. But a safety plug will do most of that by itself.

As for air leakage and not just cold air you should seal all outlets and switches. It just happens that you notice the cold air coming in but air leaking out from others is being replaced somewhere.

Bud
 
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Old 01-13-18, 09:09 AM
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Originally Posted by joecaption
Has the basement or crawl space, and attic ever been air sealed?
How old is this house?
Old homes used balloon wall constrution and the walls where open from the basement to the attic.
Rim joist been insulated!
The house is about 10 years old. It has a full basement that is unfinished. Insulation is stuffed in the rim joists currently, however, I plan to take the insulation out of the rim joists, put insulating panels in there, use spray foam to hold the panels in place, and then put the insulation back in the rim joists. The attic is insulated, but I'm not sure what your mean when you say air sealed.
 
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Old 01-13-18, 06:38 PM
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I use the foam pads. If it's really bad, you can drill a hole near the outlet and spray in expanding foam (the 1x or 2x stuff so as not to expand the wall). Then repaint the hole. Be careful to avoid drilling into the wires.
Failing that you have to insulate the walls properly.
 
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Old 01-16-18, 06:33 AM
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I may get some flak for this, but what I would do is remove the outlet (leave wires connected) and drill a small hole through the back of the box (assuming it is plastic)--just enough to fit the straw of a spray foam can, then fill the void behind the box with spray foam. Before doing that, check to see if there are spare knockouts on the top of the box, which you could open up and stick the straw through. If the box is metal, there may be a knockout in the back, which you could try to carefully push open just enough to fit the straw.
 
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Old 01-16-18, 07:26 AM
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Mossman, dealing with the cold electrical boxes was a frequent request when doing energy audits so I built up several mock-ups to test different ways to inject foam around switches and receptacles. Unfortunately all tests were poor with voids resulting from the insulation limiting the expansion. In addition, in some places the expanding foam made its way into the box which would not be good. This testing is what lead me to the contact paper covering the front. What people assume is the can foam provides necessary insulation value, but it is the air sealing that prevents the cold air from reaching that area. Block the air and the cold is held away.

Bud
 
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Old 01-16-18, 07:40 AM
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What people assume is the can foam provides necessary insulation value, but it is the air sealing that prevents the cold air from reaching that area. Block the air and the cold is held away.
Thanks for the reply! I will keep this in mind (I have several leaky outlets in my basement).
 
 

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