Put your hand near outlets on external walls.

I was testing the Christmas lights and the outlet I was using had a cold draft coming in through it. So I called my wife, out doing errands, and told her to get some of those outlet caps. She got 24, which just happened to be just enough for all the normally unused outlets on our external walls. That should help a little.

splurge for a infrared camera

How much would that cost?

in my search I found this...

http://www.metacafe.com/watch/395292...igital_camera/

otherwise, this would probably do the job.

http://www.amazon.com/Infrared-3-axi...7163498&sr=8-4

Outlet caps (child-safe) won't help. The problem is cold from inside the wall coming through the outlet wall (trim) plate. That plate has an R value of about 0.5.

Get the foam insulators to put behind those plates. They have an R value of 5 or so.

There is no direct air path from the wall to the 'slots' in the outlet. This is why every light switch and outlet in my house has those foam insulators behind the trim plates.

The cold draft went away when I put the caps on. The trim plate itself is cold, too, but at least I stopped the draft.

I thought you lived in a brand new house?

I dont see how air is getting into the walls, I would assume insulation would prevent this type of thing.

There is a vapor barrier under the siding and under the drywall. Appearantly it'* not perfect.

My house has those plastic insulators behind the outlets covers. I honestly didint know what or why we had them until this post. Cool