Daylighting (cont’d)

What are the different types of light? North light is more diffuse (and blue) and does not add heat to the building.  South light is the most desirable light and is, typically, the longest exposure, but it can bring with it glare and heat gain.  East and west light are a mix of north and south light, but west light is the harshest and tends to bring the most heat gain.  Typically, east and west light are easier to control with vertical exterior louvers while south light is best controlled by utilizing a horizontal cover that is sized based on the sun’s location in the sky during the summer and winter.

How do you handle glare from lighting? Light can be diffused on the interior by utilizing interior horizontal shades that can reflect the light up to a light-colored ceiling, or having a motorized shade system that is connected to occupancy and light sensors to maintain the level of light desired in a space.  On the exterior, light shelves can reduce glare by reflecting direct sunlight up into the space and shading the interior space right next to the window from direct sunlight.  Exterior louvers or eaves can also be oriented, sized, and spaced to reflect/block sunlight when the light tends to be harsh or creates more heat gain.  To address heat gain, it’s important to specify and install double or triple pane windows as well as include filters/coatings to the glass (like low-e).

What about lighting interior spaces? If you’d like natural light in interior spaces, you can utilize skylights, solar tubes, or even a sun-tracking array that captures and redirects natural light into a building, if your budget allows.

Daylighting is an important aspect of building design.  The best way to utilize natural light begins by planning during design and implementing during construction.  It is important to consider the siting of the building, what type of light you want in each space and the need for diffusing/controlling the light.