For small businesses with low internal loads, use 65 base degree-days for heating and cooling. For small- to medium-size commercial buildings, a base of 55 should be used to allow for higher internal loads.

2. Equipment capacity and efficiency ratings can be found on nameplate data or in the owner's manual. If these are not available, ratings can be approximated by referring to the manufacturer's catalog data. A rough guess for cooling capacity can be made by using 300 to 600 square feet per ton. Higher lighting power density and high computer or equipment loads would mean fewer square feet per ton.

3. A rough cost estimate for the Aeroseal process for both small and large commercial buildings is $0.40 per square foot.