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Case 14

OpenStudio Measure: Adding infiltration correlated for weather

[Ng, Lisa and Polidoro, Brian]

This measure incorporates infiltration that varies with weather and HVAC operation, and takes into account building geometry (height, above-ground exterior surface area, and volume). It is based on work published by Ng et al. (2018) Weather correlations to calculate infiltration rates for U. S. commercial building energy models   ( This method of calculating infiltration was developed using eleven of the DOE commercial prototype building models (Highrise Apartment, Hospital, Medium Office, Large Hotel, Midrise Apartment, Primary School, Secondary School Small Hotel, Small Office, Stand Alone Retail, and Strip Mall) (Goel et al. 2014) ( and TMY3 weather files for eight climate zones (CZ):


Climate zone (CZ) City, State (USA)
1 Miami, Florida
2 Phoenix, Arizona
3 Memphis, Tennessee
4 Baltimore, Maryland
5 Chicago, Illinois
6 Helena, Montana
7 Duluth, Minnesota
8 Fairbanks, Alaska


Ng et al. (2018) shows that when analyzing the benefits of building envelope airtightening, greater HVAC energy savings were predicted using the infiltration inputs included in this Measure compared with using the default inputs that are included in the prototype building models.


CONTAM Project FilesOpenStudio Measure


Created September 25, 2018, Updated February 13, 2020