Design Considerations: Natural Light

Windows allow natural light into a home, and thoughtful window placement and exterior landscaping provide your home with most of its daytime lighting needs. Using natural light efficiently lowers monthly utility bills, enhances the beauty of a home’s interior, and protects against health issues. But more is not always better, and light should be spread evenly throughout rooms. This is particularly important in rooms used as offices, to keep screens free from glare and to protect art, furniture, or decorations from fading due to excess sunlight.   

There are three main types of solutions to strike a balance both beautiful and comfortable: interior decoration choices, exterior features, and prioritizing window placement at the pre-construction stage of planning. 

 

Interior Decoration

  • ​Shades, drapes, and blinds block or diffuse direct sunlight. If you prefer drapes, choose light colors and loosely woven fabrics, which diffuse daylight while still offering privacy.
  • Because sunlight enters windows at different angles – downward from high in the sky at mid-day, or on a more horizontal trajectory in late afternoon when the sun will soon set – blinds offer more flexibility for east- or west-facing windows in particular. They can be adjusted up or down to compensate.
  • Natural light can be reflected throughout a room, spreading it more evenly, by using lighter shades of paint for walls, in particular in rooms with just one window. Hanging mirrors and other reflective surfaces in naturally lit areas also help to spread light evenly.
  • Interior windows – open spots in a wall between two rooms – will also draw natural light deeper into spaces.

Exterior Features​

  • Trees and shrubs can shield windows from intense sunlight, as do awnings, overhangs, and shutters.
  • Lattices, screen doors, and exterior shades allow light to pass through, but diffuse it in the process so it spreads evenly in a room.
  • Other exterior features such as walls, ponds, and sand can be used to reflect direct sun rays. The indirect light that bounces off these surfaces and through windows are a better source for interiors because it is less intense.​

Designing Homes​

  • Natural light spreads more evenly in rooms with multiple windows. Glass block and frosted or patterned glass also diffuse sunlight, and are particularly useful for skylights or windows that aren’t in the field of vision and are not valued for views. These are often set high on walls, near ceilings.
  • Light tubes (Tubular Daylighting Devices) are an alternative to skylights, which sometimes are difficult to incorporate into designs. Light tubes feature a clear plastic dome mounted over a hole in the roof and connected to a reflective tube, through which light moves toward a light diffuser installed in the ceiling of a room.
  • In hot climates, north-facing windows provide the highest-quality light without also leaving a home exposed to heat from the sun.
  • ​In cold climates, where heat exposure boosts energy efficiency, designs should prioritize east, west, or south-facing windows.