Pattern 16: Daylight from Top and Side (Cloudy)

Perimeter with No Clerestory

Vertical windows on one side are insufficient to effectively illuminate this 30’-0” deep classroom under overcast sky conditions. North-facing perimeter glazing with an 8’-0” head height provides effective daylight illuminance at only about one-third of the classroom area. The contrast from perimeter glazing and the interior surfaces of the classroom is very high, increasing the likelihood of glare. Commonly this results in the deployment of blinds and a substantial reduction in daylight performance.

Pattern 16: Daylight from Top and Side (Cloudy)

Perimeter Glazing

Pattern 16: Daylight from Top and Side

Vertical windows on one side are insufficient to effectively illuminate this 30’-0” deep classroom. North-facing perimeter glazing with a 12’-0” head height provides effective daylight illuminance at about two-thirds of the classroom area under overcast sky conditions. The contrast from perimeter glazing and the interior surfaces of the classroom is very high, increasing the likelihood of glare. The increase in vertical glazing does contribute to increased luminance at the “back” of the classroom.

Pattern 16: Daylight from Top and Side (Cloudy)

Perimeter and Window

Pattern 16: Daylight from Top and Side

The inclusion of a small vertical window at the “back” wall provides balancing illumination and washes the teaching wall with daylight. The combination of these vertical windows is sufficient to illuminate approximately three-quarters of this 30’-0” deep classroom under overcast sky conditions. . The contrast from perimeter glazing and the interior surfaces of the classroom is managed across the section of the space. It should be noted that due to circulation requirements, it is uncommon for classrooms to have the potential to be side-lit from opposite vertical walls.

Pattern 16: Daylight from Top and Side (Cloudy)

Perimeter and Skylight

Pattern 16: Daylight from Top and Side

The inclusion of a pair of translucent (light diffusing) 3’-6” X 2’-6” skylights at approximately 10’-0” off the “back” wall provides a relatively even distribution of horizontal illumination across the classroom section. Daylight through the skylights adds to the vertical surface brightness of the back wall and increases surface luminance within the classroom. This serves to reduce contrast and increase visual comfort. This configuration illuminates 85% of this 30’-0” deep classroom under overcast sky conditions.

Pattern 16: Daylight from Top and Side (Cloudy)

Perimeter, Window and Skylight (As Built)

Pattern 16: Daylight from Top and Side

The “as-built” configuration combines perimeter glazing, a pair of translucent (light diffusing) 3’-6” X 2’-6” skylights, and a small vertical window to wash the teaching wall with daylight. This combination of apertures provides excellent interior surface illuminance and a well-composed distribution of brightness. This serves to reduce contrast and to increase visual comfort, especially views to the exterior. Nearly all of the interior of this 30’-0” deep classroom meets ambient illumination goals with daylight under overcast sky conditions.

Pattern 16: Daylight from Top and Side (Cloudy)

Perimeter and Skylight Engaging Back Wall

Pattern 16: Daylight from Top and Side

This configuration combines perimeter glazing with a pair of translucent (light diffusing) 3’-6” X 2’-6” skylights in a “slot” lightwell engaging the back wall of the classroom. This combination of apertures provides a continuous wash of daylight on the back wall to balance the brightness of the perimeter glazing. Nearly all of the interior of this 30’-0” deep classroom meets ambient illumination goals with daylight under overcast sky conditions.

Pattern 16: Daylight from Top and Side (Cloudy)

Perimeter and Slot Skylight

Pattern 16: Daylight from Top and Side

This configuration combines perimeter glazing with four translucent (light diffusing) 3’-6” X 2’-6” skylights in a “slot” light well engaging the back wall of the classroom. This combination of apertures provides a continuous wash of daylight on the back wall to balance the brightness of the perimeter glazing. Nearly all of the interior of this 30’-0” deep classroom meets ambient illumination goals with daylight under overcast sky conditions. Though substantially increasing surface luminance, the horizontal area exceeding 300 lux is nearly unchanged with the doubling of skylight area.

Pattern 16: Daylight from Top and Side (Cloudy)

Perimeter and South Clerestory

Pattern 16: Daylight from Top and Side

This configuration combines perimeter glazing with a continuous 2’-0” translucent (light diffusing) south facing clerestory above the back wall of the classroom. Given the directionality of the clerestory, this configuration creates high illumination levels at the center of the classroom, with somewhat less surface brightness on the back wall. Nearly all of the interior of this 30’-0” deep classroom meets ambient illumination goals with daylight under overcast sky conditions.

Pattern 16: Daylight from Top and Side (Cloudy)

Perimeter and North-Facing Clerestory

Pattern 16: Daylight from Top and Side

This configuration combines perimeter glazing with a continuous 2’-0” transparent (clear glass) north facing clerestory opposite the back wall of the classroom. Given the directionality of the clerestory, this configuration creates high surface brightness on the back wall, balancing the brightness of the perimeter glazing. Nearly all of the interior of this 30’-0” deep classroom meets ambient illumination goals with daylight under overcast sky conditions.