For both design and evaluation purposes, it would be useful to have a method for estimating energy saving when a heat exchanger is installed in a specific building. This heat exchanger analysis is part of ongoing work in the development of an overall ventilation design, analysis, and management model. The BIN method is used to calculate seasonal energy usage with and without a heat exchanger in the building. A series of test analyses was conducted to compare predicted energy savings as functions of minimum ventilation rate, percent slatted floor, heat exchanger effectiveness, and number of animals in the building. Energy saved by a heat exchanger is dependent on the minimum ventilation rate. If it is desirable to increase minimum ventilation rate for air quality purposes, the addition of a heat exchanger could keep energy costs at or near their previous level. Heat exchangers will generate the largest annual savings in buildings that are large energy consumers. Seasonal heating costs may be reduced by one half as percent slotted floor increases from 50 to 100%. Effect of slotted floor in terms of energy savings is similar with or without a heat exchanger.