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After this ice storm/sleet and snow in NC (winter storm Jonas), I've noticed cold air seeping through the 1st floor electrical outlets and light switches (they are only on the back side of the house). I walked around the house and no other leaks anywhere else. I did open up the outlet and it there were not any holes anywhere in the box. We have a crawlspace. No leaky outlets or switches on the 2nd floor.

How should I handle this? I thought about trying the insulation pads first that are already cut out? Here is an example:

http://www.amazon.com/gp/product/B00...=sr_1_1&sr=8-1

I was just surprised at the cold draft coming through the outlet!
 

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There have been thousands, possibly millions of those installed to stop drafts only to find cold air is coming out into the room at base board level too. It would help the locals more to just pitch a dollar bill out the car window occasionally while traveling rather than paying those dollars to china.

That's my opinion and I'm sticken toit.:biggrin2:
 

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First, there are holes in your outlet box -- where the wires enter, at least.

Air from the house normally goes INTO the outlets, and then up and out the wall top plates, due to the stack effect. Your lower levels are under negative pressure (sucking in) and the upper levels have positive pressure (blowing air out).

Interesting that in your case the air is coming OUT of the outlet. To me that implies that the TOP of your crawl space is sealed well enough that the path of least resistance is for its air to enter your house through the outlet -- and, afterward, it's eventually escaping upward somewhere else.

The quick fix is to use those foam outlet inserts you linked, and also seal the bottom of your base boards with caulking.

The larger fix is to air seal the crawl space.
 

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I use DAP foam around the boxes where the drywall opening is, a bit into the boxes, where the wires enter, then the foam pads while the foam is still wet, so that it makes a good seal.

Also going around and making sure that all windows and doors are not leaking any outside air into the house. You may have to take off the trim and use foam in a can to seal those openings.

I use the Retro-Door seal insulation, which is on a Aluminum channel and is nylon covered, with the foam core inside. Have not had any problems with my house feeling cold after doing all of that.
 

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How old is this house?
Really old houses used balloon constrution that would need fire blocking at the top and bottoms of the walls to stop air flow behind the walls.
Newer homes need to be air seal anyplace wiring or plumbing is run through the top and bottom plates ceilings in the attic where any lights, vents, plumbing was run.
Rim joist also should have been insulated with 2" foam.
Just sealing the box may stop some of the air from coming out, but nothing to keep cold air from getting into the stud bay and cooling down the whole wall.
 

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Discussion Starter #6
How old is this house?
Really old houses used balloon constrution that would need fire blocking at the top and bottoms of the walls to stop air flow behind the walls.
Newer homes need to be air seal anyplace wiring or plumbing is run through the top and bottom plates ceilings in the attic where any lights, vents, plumbing was run.
Rim joist also should have been insulated with 2" foam.
Just sealing the box may stop some of the air from coming out, but nothing to keep cold air from getting into the stud bay and cooling down the whole wall.
This is a new construction home (within 2 years). These leaky outlets are only in the back of the house on the 1st floor. I checked everywhere else. Should I get under the crawl space to look at the wall space underneath, or won't really find anything there? The insulation all looks intact under there.
 

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Discussion Starter #7
First, there are holes in your outlet box -- where the wires enter, at least.

Air from the house normally goes INTO the outlets, and then up and out the wall top plates, due to the stack effect. Your lower levels are under negative pressure (sucking in) and the upper levels have positive pressure (blowing air out).

Interesting that in your case the air is coming OUT of the outlet. To me that implies that the TOP of your crawl space is sealed well enough that the path of least resistance is for its air to enter your house through the outlet -- and, afterward, it's eventually escaping upward somewhere else.

The quick fix is to use those foam outlet inserts you linked, and also seal the bottom of your base boards with caulking.

The larger fix is to air seal the crawl space.
You're correct - the floor and crawl space seem to be very well sealed when I inspected the construction at different phases. And the air leak test had very good results. the crawl space is not completely sealed and conditioned though.

The outlets leaking air only on the back side of the house and only on the 1st floor.

Thanks for the recs.
 

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Hi HB, a couple of points to help.
Even when air leakage tests are good, a new hours will still have a lot of natural air leakage. If it were built tighter than 0.35 ACH (air changes per hour) then they should have included some form of mechanical ventilation, a bath fan running automatically or an HRV. My point is, air exchange is still happening, in many places.

Where you are just seeing (feeling) it in the back may only be because that is an entrance point. For every cubic ft of air that comes in, a similar volume must go out. So, sealing places that don't necessarily feel cold can reduce the total leakage. You block either end of a straw and you get nothing to drink.

Yes, inspect all wire penetrations you can and seal them. They have a fire rated caulking or can foam where vertical air flow is a fire concern.

But, there are many more places to check for air leakage that may have been overlooked during construction. Did they give you the CFM50 or ACH number?

My personal solution for leaky outlets and switches is a mask of contact paper cut to fit over the switch or receptacle and then covered by the plate. This approach helps to seal between the box and the drywall. Air sealing around these boxes isn't a big issue for total energy loss, as stated there is a lot of leakage anyway, but it is a comfort issue when you can feel those drafts.

Bud
 
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The foam seals for your outlets and recepts will help.
 

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Everything they seal helps, but air sealing has a technical detail, every cfm you block, infiltration or exfiltration, reduces the total exchange by 0.5 cfm. It is a spin-off of the half fan rule where a 100 cfm exhaust fan only results in 50 cfm of fresh air. Judy Roberson provides a good summary of Palmiter's "half fan rule" and Sherman's "50% rule" here:
http://www.cbe.berkeley.edu/research/pdf_files/Roberson_thesis2004.pdf
Starts at page 41 and only a few pages on this topic.

This is not a reason to not air seal, but it does explain why the results may seem to lag the efforts. There's the old counter to air sealing that when you seal one leak that air simply moves to another location. As it turns out, they were half right.

Bud
 

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Can you blame them. I call these types of tasks as Cold and Rainy day chores.
Not at all. Every bit helps.

Most customers want to have some input on things so we tend to show them how to best do it and then let them do what they can.
 

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The back side of your house would appear to be facing the prevailing wind . The wind load is finding an exterior entry point ......so must you !

Usually , in modern homes with tyvek or plastic wrap this problem is minimized .
 
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