Post-occupancy evaluation of the Forrestal Building

Abstract

A post-occupancy evaluation was performed on the Department of Energy Headquarters Building (the Forrestal Building) in Washington, D.C. The lighting in the building was retrofitted with new, more energy-efficient, components to meet energy target guidelines. Occupant responses to the indoor environmental conditions, particularly the lighting, were studied to determine the impact of the relighting on the building inhabitants. In addition, physical measures of the lighting and other environmental conditions before and after the relighting were compared. The post-occupancy evaluation employed a questionnaire about the environmental conditions and physical measures of the space (lighting, space, noise, temperature, etc.). A total of 244/220 people participated (before and after the relighting, respectively). Physical measures were taken at 100 work stations before the relighting and 75 after. Analysis of the physical measurement data indicated generally higher lighting levels with more even distribution of luminances in the offices. Occupant response to the changes in the lighting was generally quite positive. The relighting was perceived to have improved the appearance of the building substantially, as well as the lighting within individual workstations. Finally, guidance is given for doing post¬ occupancy evaluations as part of other relighting initiatives.

Using end‐user surveys to enhance facilities design and management

“…The survey instrument was based on the work of Sanders and Collins (1995), who reported on the post-occupancy evaluation of the government-owned and -operated Forrestal Building. The opportunity to voluntarily participate in the study was advertised, by posting flyers in the library facility.…”

“…A forty‐item questionnaire was developed, which sought to evaluate the effect of lighting design on end‐users' perceptions and opinions at the existing on‐campus library and to gather general opinions regarding sustainability from library end‐users. The survey instrument was based on the work of Sanders and Collins (1995), who reported on the post‐occupancy evaluation of the government‐owned and ‐operated Forrestal Building. The opportunity to voluntarily participate in the study was advertised, by posting flyers in the library facility.…”

Lighting for high-quality workplaces

“…Several studies have also found that people prefer relatively bright vertical surfaces (Newsham et al, 2004a(Newsham et al, , 2004cOoyen et al, 1987;Sanders and Collins, 1996;Veitch and Newsham, 2000). Expressed as luminance values, preferred values for walls or cubicle panels should be greater than 30 cd/m 2 (Loe et al, 1994;Newsham et al, 2005;Veitch and Newsham, 2000).…”