Natural light is highly coveted in many homes. Homeowners take advantage of daylighting for different reasons but most have to do with how an abundance of natural light imparts spaciousness and airiness to a property. Homes are not meant to be stuffy, after all. As windows are some of the best ways to harness natural light, they’re the best place to start for anyone looking to make the most out of daylighting.
Windows and Daylighting
Effectively pulling off daylighting means properly utilizing windows. A handful of guidelines are usually followed but, fortunately, they are not as complicated as you might think. Some of the daylighting considerations you should keep in mind include:
- Exterior Shading: Light shelves, overhangs, shutters and the like help diffuse natural light entering a window. They offer a means of controlling light to achieve a level most comfortable for you.
- Glazing: The kind of glass a window uses affects how much light is let in. To let in as much light as possible, it would be best to go with a window with a low to moderate shading coefficient and high visible transmittance rating.
- Apertures: How big a window is and where it is located also affects how much natural light can be enjoyed. As a general rule, for instance, at most latitudes, light travels into a room at a distance equivalent to 2 ½ times the height of the top of window.
- Window orientation: South-facing windows offer the highest level of natural light. This is great for daylighting but will mean unnecessary heating in areas where the climate is generally warm unless window treatments are used.
A Quick Tip
As sun exposure varies from area to area, so will the level of natural light that homes in various parts of the country will be able to enjoy. As such, the daylighting considerations mentioned above may be tweaked to address a home’s particular needs. For instance, a south-facing window in a home located in a warm climate may not require that much shading if it uses energy-efficient glass that keeps heat let in by a window at bay. As homes differ, how daylighting is employed will also be different. The key is in knowing what you want to achieve exactly from daylighting.
Some Terms to Remember
- Ambient lighting. Refers to general illumination; defines lighting requirements for areas without specific tasks.
- A translucent or opaque element for shielding a source of light at certain angles from direct view.
- Cut-off angle. A viewing angle from which a source of light can no longer be seen due to an obstruction.
- Diffuse lighting. Indirect lighting that can come for various directions or angles; the source is commonly not seen.
- Indirect lighting. Lighting achieved via reflection from typically ceilings and walls
- Task lighting. Light provided for a certain task, specifically trained in an area as opposed to ambient or general lighting
- Veiling reflection. When light reflected on a surface obscures the details of that surface, like when glossy magazines are rendered unreadable under bright and direct lighting.
Eric Minkiewicz is the President of Renewal by Andersen of Eastern New York, a company that offers replacement windows and doors in the Capital Region and Hudson Valley. When he’s not in the field, he shares home improvement tips and other industry knowledge through the company blog.