Calculating Savings

Reducing Air Infiltration

When you tighten your home, you reduce the air changes per hour (ACPH) of the home and consequently you reduce the amount of energy required to heat all that incoming air.  The following formula is used to determine annual energy saving from reducing your ACPH:

Formula

Volume (cuft) x ( ACPH current - ACPH proposed ) x 0.018 x 24 x HDDZ x Cost/Unit of Heating Fuel / Btu/Unit of Heating Fuel /  Heating System Efficiency  = Annual Dollars Saved

Variables Described

Volume = Length x Width x Height of House
ACPH = Air Changes per Hour. See Air Infiltration Table.
HDDZ = Heating Degree Days. See HDDZ Table.
Heating Fuel Cost = Get from your bill by dividing units / cost.
Btu/Unit = Get from Fuel Btu Table.
Heating System Efficiency = Get from Heating System Efficiency Table.

Back | Top

Last Updated: 01/21/2007