This measure installs a strip curtain on a walk-in freezer or cooler where none existed before. Savings occur from load reduction of the refrigeration system it also reduces load on the store's HVAC heating system, assuming grocery stores heat most of the year. However, there are a number of factors that are difficult to account for and can greatly impact these savings. One factor is the temperature of the surroundings, this is used to determine infiltration air temperature, which can greatly affect savings. The other is strip curtain takeback, which refers to increased door open time after a strip curtain is installed, and can also have a huge effect on savings.