Air seeks entrances from the bottom of a house, moving up to the attic. This is called the "Stack  Effect." It is important that this air not reach the attic, so the priorities are ATTIC first and then the BASEMENT.

       In the attic, some sources of air leakage are wire holes, plumbing pipes, chases, chimneys, recessed lights, bathroom fans and AC/HVAC ducts, so it is most  important to make sure these are sealed before adding more insulation.

     The rim joist in a basement allows air to enter from the outside, which then travels up toward the living spaces in the house and eventually reaches the attic.  When  low-E foam is used to air seal, this becomes the insulation and air barrier.

​       Other sources of air leakage are windows, doors, exterior walls, outlets and interior walls that intersect with the attic ceiling.


There are different ways to determine air leakage:  Visual, De-Pressurization Test (Blower Door) and Thermal Imaging.

     1. Visual.  We will look for obvious areas where air is entering from the outside in the attic, basement and main house.

      2. Blower Door Test. A  blower door is a machine used to measure the airtightness of buildings. This will tell us the amount and exact location of air leakage. 



KJ's Energysavers LLC  603-577-1772

KJ's Energysavers LLC

Energy Insulation Specialists

Blue color shows cold air entering a corner of the ceiling.

Red/purple shows heat loss.  

3. Thermal Imaging. Employing a FLIR 7, when used with a Blower Door, gives an enhanced imaging of cold air entering a house.