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Blower Door Test Completed! 0.45 ACH50!

Energy use in a building scales with air infiltration.  Decreasing air infiltration can have a huge impact on heating costs.  The plot in this article ( illustrates things nicely.  Heating energy decreases linearly with decreasing infiltration while conduction losses through the insulation change little with air infiltration.   A tighter air barrier has several implications.  It leads to lower energy bills and it also leads to a more resilient structure that is less susceptible to moisture.   In addition, balanced mechanical ventilation provides fresh air more effectively than random infiltration and is a controlled route for energy capture/release through an HRV/ERV.

Infiltration is typically measured with a blower door test.  A fan blower is placed in a door to the exterior.  The fan is then turned on and the differential pressure it creates causes the house to leak from exterior to interior (depressurization) or vice versa (pressurization)…

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