Taking an Integrated Approach to Daylighting

Brought to you in collaboration with the publishers of Professional Builder and Custom Builder magazines

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Making the most of natural light in a home requires an integrated approach to the exterior and interior design. 

The most effective technique for managing daylight is to orient the house so its largest facade faces south and has the most windows. While that orientation is not always practical, it provides a general design guideline. 

A house’s orientation also has a dramatic impact on heating and cooling costs. Because the sun is much higher in the sky in summer than in winter, overhangs and trees can effectively block the heat of summer sun. In the winter, the sun's angle is lower and its rays will shine below the overhangs.

Here are a few other design considerations for maximizing visual comfort and reducing energy use:

Blinds, curtains, and shades
Venetian blinds, curtains, and shades are the ultimate low-tech lighting control. Blinds can be tilted upward to direct incoming sunlight toward the ceiling so it becomes ambient light. And translucent shades and sheer curtains block direct sunlight and turn it into softer ambient light.

Artificial lighting and controls
There are many energy-efficient lighting choices available to enhance occupant comfort, convenience, and ambience throughout the house. The most popular bulbs available are halogen incandescents, compact fluorescent lamps (CFLs), and light-emitting diodes (LEDs). Daylight-responsive electric lighting controls incorporate photocells to sense the available light and dim or turn off the electric lighting system to create an ideal lighting environment. 

Reflective surfaces
Light reflects off internal walls, ceilings, and floors—particularly glossy surfaces, light-colored finishes, and mirrors. Because mirrors reflect almost all light that hits them, they are best placed in areas that have low natural light conditions, such as entryways, hallways, and basements.

Interior paint colors
Bright colors reflect light more easily than darker shades. Light colors also make spaces feel larger and brighter, so daylight is easier to use as task lighting. Avoid paints with a gloss sheen on large surfaces, as these can create annoying glare.

Arrangement of furniture
Furniture arrangements may block light and create shadows. Keep large pieces of furniture away from windows and other natural light sources, and make sure furniture arrangements have corridors that allow light to reach across rooms.

Deciduous trees with high, spreading crowns can be planted to the south of a home to provide maximum summertime roof shading. Trees with crowns lower to the ground are more appropriate to the west, where shade is needed from lower afternoon sun angles. Avoid planting trees on the southern sides of homes in cold climates, because the branches of these deciduous trees will block some winter sun.