The three attached IR images were taken on January 27th at about 10:40 AM. They are three separate brick wall sections of a continuous, east facing walll of a one story school in Vermont, built in 1961.  The morning was very cloudy and the temperature outside was about 30 deg.F. There are classrooms on the other side of these walls, at about 68 deg.F. There is nothing else on the other side of these walls except maybe a homosote bulletin board. The brick wall is attached to a CMU block wall which is the interior finish of the classrooms. There is no heating or ventilation in this area of the walls. There is some indication that there is a possiblity of vermiculite insulation in the open cores of the CMUs. Even if there were vermiculite that had settled, the open cores of CMUs are not connected horizontally, only vertically so I would not expect an even line across the wall. I also looked at these from different angles, with no change.

Any thoughts on why there is such a clear demarcation between the lower and upper parts of these walls, with an average of about 3 deg. difference? Note that in two images the slope goes down to the right, but in the third image it slopes down to the left.

 EDIT- It seems that I can only attach one image per post. For now I have attached the other two images to two more posts.

---

Brad Cook
Building Performance Services LLC
BPI Accredited
Warren, Vermont
Level I Thermographer
"Always look at the WHOLE picture"
"The more you look, the more you see"
"You can never take enough pictures"