One look at the infrared image of this staircase will make you feel cold while you sit at your computer. The blue streaks that are in the image are a result of the cold air coming into the house during a blower door test and cooling the surface temperature of the stairs. Even before the blower door was running we were able to feel air moving through this house. So Cold, especially this morning because it was -9 degrees F!

     This house was built in the early 1900′s and the sheathing on the exterior walls was comprised of 8″ – 12″ boards instead of plywood that we use today. Boards were used because plywood was not available and structurally the boards did a pretty good job. However, there were a lot of air gaps between the boards, especially as they shrunk over time.

     Directly under this set of stairs is the stair case to the basement and the exterior walls that surround it are not insulated. As a result, the cold, dense air pours in through the cracks creating a very cold breeze in the house. The solution? Stop the air and add insulation at the same time. The best way to accomplish this would be to apply commercial spray foam in the walls but a less expensive option would be to add layers of rigid insulation and use small cans of spray foam to seal the rigid insulation tight to the studs around the edges.