Aerial Thermography of Membrane Roofing

The following vertical (orthogonal) aerial thermograph was shot in March, 2011. It's from an atypical southeast-to-northwest flight line across the east end of the Boise State Campus.

I was "shooting" wide-meaning at relatively low resolution (about 2' pixels) capturing the paths of geothermal lines through the older part of the campus. The southwest portion of the Taco Bell Arena just happened to be in the image.

The red square indicates an area of concern on the membrane roof of the arena. This relatively warm patch is consistent with the classic signature of water accumulated beneath a roofing membrane.

The water is relatively dense and absorbs heat through the day. After the sun dips below the horizon the water cools more slowly that structural elements and therefore produces the relatively warm thermal signature. This signature doesn't necessarily pinpoint a leak, but it does show where the water has accumulated.

If this signature is in fact water beneath the roof it's quite a significant find-I'd estimate that it's some 300 square feet in size. We immediately sent the image in to BSU's maintenance folks.

That's not the only finding of interest in this image. Geothermal lines are obvious in the upper right portion of the image and even between a couple of the buildings adjacent to the pavillion. The Student Union Building (upper left) also has some areas that could be considered interesting.

L