There are two main areas of inquiry; first, how well does the existing lighting perform. This includes both the daylight contribution from the windows, as well as the ambient electric lighting. Second, since we learn quite rapidly that the space is darker than recommended, what are some improvements that can be made to allow better daylighting of the space?

Assess Existing Illuminance

• Measure illuminance data for two lighting conditions: daylight only, and daylight plus electric
• Spot illuminance measurements at each desk to measure task lighting

Explore Improvements to Lighting

• Research daylighting guidelines
• Research limitations of specific site/space
• Luminance data for surfaces in space
• Build daylighting model of the existing space, along with modifications
• Test Daylighting model under Artificial Sky

• Establish grid
• Record illuminance readings
• Plot as illuminance map

Methodology: Illuminance Map

To measure the horizontal distribution of illuminance at the height of the task surface (approx. 30 inches), we established a 4 foot grid for data collection points that would remain consistent between each data series.

Using Sylvania illuminance meters and a 30" stick base, measurements were taken at each grid point under two different lighting conditions: daylight only (all electric lights off), and daylight plus ambient electric light (overhead lights only; all task lights off). Additionally, we took spot measurements at each desk directly under each operable task light, at the work plane.

• Research daylighting guidelines
• Research limitations of specific site/space
• Luminance data for surfaces in space
• Model the existing space, along with modifications

Methodology: Daylighting Redesign

Surface reflectance values for surfaces in the space were measured with a Minolta Luminance Meter. A model of the existing space was built at 1/2" = 1'-0" scale, based on construction documents and on-site measurements, including the surface reflectance measurements. In addition to the existing condition, the model was designed to allow the implementation of three other major modifications, both individually and in various combinations. These three modifications are:

A. Move conference room volume (and attached low ceiling) away from South wall, relocate to East wall.
B. Insert strip skylight (running East-West) as far back from South wall as the Third Floor would allow (in-line with existing small skylight)
C. Add window (with light shelf) in West wall. (This is the only wall that is not part of the historic facade, so adding openings in it is allowed)

In addition to assessing these modifications separately (A, B, C) we also assessed all the possible combinations of these modifications (AB, AC, BC, ABC). A total of eight (8) different configurations were modeled and tested in the Artificial Sky, including the existing configuration.