The high installed density of Nu-Wool Premium Cellulose Insulation results in reduced air movement through the product.  This reduced air movement creates a tighter building envelope, as required by current building codes. 

Building air tightness is a measure of how much air passes through the building envelope at a specified reference pressure.  A Blower Door is a diagnostic tool that quantifies the air tightness of a building.  Air tightness measurements are typically presented in Air Changes per Hour at 50 Pa (ACH50).  The 2012 International Energy Conservation Code requires all new homes to have a blower door test, to verify that the air leakage rates do not exceed 3ACH50 for climate zones 3-8 and 5ACH50 for zones 1 and 2.

Houses insulated with Nu-Wool Premium Cellulose Insulation routinely achieve the air tightness requirements of the IECC without costly additional air sealing products.