Using this Guide

There are approximately 20 unique daylight patterns available on this website, each designed for easy identification, navigation and comparison. Every pattern has a number and a title, such as Pattern 2: Window Area, which includes a hyperlink to a self-guided slideshow.  The slideshow is carefully sequenced and narrated to tell a story about the relationship between design criteria and daylight performance. Every pattern follows the same format that includes a suite of technical images, graphs and text to formulate a holistic description of the pattern. The diagram below is an example of the elements within this information suite. 


Pattern Title
Indicates the pattern title and number.

Pattern Subtitle
Indicates the specific geometric, temporal, or other change in the design case illustrated.  Each pattern has several ‘pattern steps’ and these are organized with the Pattern Subtitle.

Navigation buttons for the pattern slideshow allow you to move forward, backward and pause.

Film Strip
Indicates the position of each simulation case or pattern step within the larger pattern sequence.

Narrative Text
Describes several performance attributes of specific pattern steps and their overall contribution to daylighting within the space.

Shows the geometric and visual illustration of a specific design case from a fixed point of view.  Each pattern step uses the same point of view in order to easily show the effect of the design change.

False Color Luminance Map
The false color luminance map shows surface reflectance ranges from the same perspective as the rendering.  The colors represent different luminance values in absolute terms (as measured in candelas per meter squared) and these maps are a good tool to understand surface brightness and glare potential. It is difficult to use a rule of thumb to understand luminance data, but values within the range of 20 to 2000 cd/m2 meet commonly accepted interior surface brightness criteria for many space types under daylight conditions.

Luminance Scale
A visual scale of the false color luminance maps that notes the luminance value associated with each color. All of the patterns have been normalized with the range from 10 - 2500 cd/m2.

Floor Plan and Lux Map
Indicates illuminance levels as measured on a horizontal surface at 30” above finished floor superimposed over the space floor plan. Areas below the selected criteria level, usually 300 lux (~30fc), are indicated in gray. These areas fall below commonly accepted ambient illumination levels. The 300 lux level is indicated by a dashed red iso-lux contour line. Areas above 2,000 lux (~200fc) are bounded by a black hidden line. These are areas where light levels might exceed comfort criteria for excessive illumination.

Lux Scale
A contour map of lux levels overlaid onto the floor plan. Usually 300 lux (red-dotted line) is used to establish a threshold for minimum daylight performance. Regions that fall below 300 lux  are shaded in gray as they do not meet this criteria. 2,000 lux (black-dotted line) establishes an upper limit for daylight beyond and exceeding this value may be an indication of visual discomfort.

The cut-away section and/or elevation drawings describe the architectural geometry of the specific design case within the pattern. In some cases illuminance information is included to more explicitly describe the relationship between section geometry and corresponding daylight illuminance.

Percentage of Floor Area Above 300 lux
Indicates the percentage of the floor area that exceeds 300 lux (30 fc), or the selected illuminance criteria.

North Arrow
Indicates the building orientation relative to the Floor Plan and Lux Map.

Sky Condition
Indicates whether the current pattern step was conducted under clear or overcast sky conditions.

Time of Year
Indicates the time of year under which the current pattern step was conducted.. These are typically December 21st (winter solstice), September 21st (equinox), or June 21st (summer solstice).

Time of Day
Indicates the time of day under which the current pattern step was conducted.