Blower Door (Air tightness) Test

A blower door test measures the airtightness of a building under specified levels of pressure, namely infiltration and exfiltration under standard pressure "Pascal 50."  Current 2015 IECC standards as adopted by the State of Illinois require less than 5.0 ACH ( air changes per hour)  at P50 (Pascal 50) for new construction.  We conducted a test on 9.25.15 recording an ACH of ~ 17.00 at P50.   Passivhaus Institut certification requires .6 ACH at P50 for new construction and 1.00 ACH at P50 for renovation. Over the course of construction, several blower door tests may occur to assess changes in air tightness.  For instance, we conducted a blower door test on different areas of the solid exterior walls after applying a continuous air and water barrier - Prosoco on the outside of the masonry walls and lime mortar parge on the inside. Then in late 2016 after installing the windows and doors and making a series of roof penetrations we conducted a whole house blower door test and achieved .36 ACH at P50.  Then after completing the interior insulation and all roof and wall penetrations we conducted another test where we achieved .27 ACH at P 50.  We plan on conducting one final test after the drywall and all fixtures are installed and the construction is deemed complete.


AVG 145 CFM AT Pascal 50.  ACH = .27



AVG 190 CFM AT PASCAL 50 = ~ .36 ACH

whole house blower door  11.8.2016

ach 160 cfm at Pascal 50

Whole House Blower Door 9.15.2015

AVG 5785 CFM At Pascal 50 = ~17.00 ACH