A Survey of Occupant Load Factors in Contemporary Office Buildings

Abstract

Occupant load data are obtained from two survey methods applied in 23 office buildings located in the Washington, DC area. The two survey methods include a building walk-through and a telephone survey. The telephone survey requires substantially less time and effort to complete, but is dependent on building management's knowledge of the occupancy characteristics. The walk-through approach requires a review of building drawings and an onsite walk-through of the building.

Data are presented on the magnitude and distribution of the loads. The data is sorted according to the following groups: open plan office designs v. well-compartmented office designs, and government (federal and county) v. private sector tenants. Statistical summaries of the data are presented. Buildings that are primarily composed of open plan office designs are found to have greater occupant load factors than buildings composed of well-compartmented office designs. County government office buildings are found to have slightly greater occupant load factors than federal government buildings. Federal government buildings have smaller occupant load factors than private office buildings. The mean occupant load factor for all buildings is 248 ft²/person. The telephone survey technique yields a slightly greater occupant load factor than the building walk-through technique. However, because the two approaches yield relatively similar results, both are considered to be comparable in assessing office building occupant loads.