At six floors below the aperture, courtyard glazing starts to lose its effectiveness in providing diffuse sky illumination. However, the courtyard does provide views to the exterior and some balancing illumination to reduce contrast across the office section. Since the floor plate is narrow, 85% of the floor area receives sufficient daylight to meet 300 lux of horizontal illumination.

Two floors below the aperture, the courtyard glazing provides balanced illumination across the section, reducing contrast, and providing high levels of diffuse daylight at the office workstations. 100% of the floor area is illuminated at levels exceeding 300 lux.

In this case, the open office area is illuminated by glazing from only one side. The absence of a central courtyard creates a unilaterally illuminated space. Despite the narrow section depth of 36’-0”, the perimeter is quite bright while the back wall is substantially less illuminated. Though the narrow section of the office floor plate is largely illuminated from one side, the contrast of perimeter to core creates a “cave” effect, which often results in blinds being closed and daylight performance being substantially diminished. Since the floor plate is narrow, 85% of the floor area receives sufficient daylight to meet 300 lux of horizontal illumination.

A four-story 20’-0” x 36’-0” courtyard provides effective daylight illumination to the third floor of the offices building. Courtyard glazing provides balanced illumination across the section, reducing contrast, and providing high levels of diffuse daylight at the office workstations, though surface brightness from the courtyard is beginning to dissipate. 100% of the floor area is illuminated at levels exceeding 300 lux.

A four-story 56’-0” x 36’-0” courtyard provides effective daylight illumination to the third floor of the offices building. Courtyard glazing provides balanced illumination across the section, reducing contrast, and providing high levels of diffuse daylight at the office workstations. 100% of the floor area is illuminated at levels exceeding 300 lux. A small patch of carefully controlled direct sunlight at the aisle way provides sparkle and additional diffuse light on the ceiling.