This home has a current air tightness rating of 16ACH! That is similar to leaving a window completely open all year round. The best place to start is the place most often neglected, the roof. With our innovative solutions and experience as leaders in Canada for air tightness achievements, we are targeting <0.5ACH for our final air tightness rating, or less than size of your fist as a comparison. This will be complemented with indoor air management.