Building Model Details

The building that was modeled is based on the default inputs in eQUEST for a low-rise multi-family residential building. Minor changes were made to reflect the expected performance of an existing building (as compared to new construction).

The changes that were made are:

• Heating system was changed to a baseboard distribution system with a central boiler
• Existing windows were modeled as single-pane clear with thermally unbroken aluminum frames R-0.83, SHGC 0.86
• The number of doors to the building were decreased
• The number of windows in the building were increased to a 20% Window-to-Wall Ratio (WWR)

The building was modeled in the following cities: New York, NY, Chicago, IL, Pittsburgh, PA. The baseline air Infiltration value for windows was based on Energy Star requirements for windows which has a maximum allowable value of 0.3 CFM/SF.

The air Infiltration value for windows was based on Serious Materials Data Sheets for SeriousWindow 501 Series with SG 8 Double Hung window which has an Air Infiltration value of 0.02 CFM/SF. The performance of this window is R-5.0, SHGC-0.26.

The wall was assumed to have an infiltration value of 0.038 CFM/SF.

The model was created using eQUEST defaults to represent a “typical” multifamily residential building. eQuest defaults are most similar to new construction, so it is expected that an existing building would perform worse due to lower efficiency boilers, pumps and envelope design.