No Insulation at the Rim Joist

Had a rare chilly day in Houston last week (actually several). Conditions allowed us to capture this infrared image of a $3M home.

Hey Chuck, educate me and tell me what I am looking at.

I see an open door and a yellow streak, what does that indicate.?

Marcel :slight_smile:

Sorry for the lack of context. The image is the side of the house. The yellow band is the heat loss that is occurring at the joist ends between the 1st floor ceiling and the 2nd floor (you can see the joist ends in the band). The builder did not insulate the space between the joists supporting the second floor at the perimeter. BTW: the vertical stripe at the lower left is a Freon line to a split room type heat pump in one of the garages.

Here’s a couple more shots.

Thanks Chuck, I see it clear now.
Nice pictures. Amazing to see the temperature differences.

Marcel :):smiley:


I find more of these cavities empty, than I do properly insulated.

Is there an HVAC duct between floors?

Those are dollar signs ($$$) flying out of the house.

I’ve just never had one yield that distinctive an image from the exterior before, so I thought I would share it for its novelty sake. This was through a three coat stucco system. I was actually trying to pick up moisture in the stucco, because the house has a lot of stucco issues, but we hadn’t had much rain for a while (except that day).

I’ve inspected this house three times now. First when my client purchased it in 06 (with two follow-up reinspections), then again in 08 and once more in 09. Client has never lived in it yet. It’s interesting to see how the problem areas have progressed over the years with no one living in the house. Inspecting it annually is lucrative, but makes for a very long day. The last report ran 75 pages long (six HVAC systems). A bunch of the wood windows are rotted, so she is contemplating a $128K proposal to replace all of them with mahogany:shock:.

Good images! We see this sort of thing often. Regardless of the climate, rim-joists should be insulated AND air sealed. It is not enough to simply push fiberglass batts into the spaces! The big problem with this area is it is a source of air leakage at the floor level and that causes major discomfort problems. You can see some of this in one of your images. I suggest you enhance air leakage either with a blower door test or by turning on the house vent fans.

Existing homes can often be retrofitted by blowing cellulose into the area, either from inside (floor or ceiling) or from the exterior using “bag and blow” technique. Of course a follow-up inspection after the work is also recommended!

Thermally yours,

John Snell
ASNT NDT Thermal/Infrared Level III #48166
Snell Infrared

This looks as if the client has ‘air wash’ going through unsealed fiberglass insulation.