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Does anyone know of a way to calculate air infiltration which is any better than a SWAG using the blower door test and calculating based on 50 pascals or just estimating ACH based on perceived tightness?
I find that most methods being used significantly overstate infiltration rates. This becomes apparent when you compare actual usage data to calculated. I think this is due to the non lineal nature of infiltration. The convective infiltration will vary greatly based on the height of the building, elevation of the penetrations in the structure (building with gaps high and low will flow) and the outdoor temp.
Is this just the nature of the beast or is there a better way?
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