Green Renovation: Adding Skylights, Part 2
Part 2 of a six-part series, Green Renovation: Adding Skylights
The first article of this series examined some basic structural requirements when adding skylights to brighten up your old house. This article explores some other important considerations of skylight installation.
Skylights and Energy Efficiency
When it comes to energy efficiency, skylights should be considered the same as windows. Get low-e, double-paned, argon-filled skylights to match your climate. Your skylights should protect against too much solar gain (heating) in hot climates, or should allow some solar gain and stop heat loss in cooler climates.
In a hot climate, venting skylights, though considerably more expensive, are an effective method of releasing heat as it rises to your ceiling.
The low-e coated windows also will greatly reduce the amount of ultraviolet radiation passing through the glass, thus protecting furniture in the room.
For energy efficiency, be sure you get glass skylights, not the less-expensive domed, plastic ones that have neither energy-efficiency nor longevity.
Types of Skylights and Costs
Generally, there are two kinds of skylights, curbed and curb-mounted. A curb-mounted light sits atop a curb made of either 2x4 or 2x6 lumber. Some homeowners prefer 2x4 curbs, as they keep the skylight closer to the roof and less obtrusive. However, most prefer 2x6 curbs, because they keep the light up off the roof, helping to protect it from splashing rain or dams of debris.
A curbed skylight has the curb attached and mounts flush to the roof. It's more expensive but a little easier to install, since you are not building the curb. When it comes to flashing, the procedure for a curbed light is similar to lights that are curb-mounted. However, a curb-mounted skylight is much easier and cheaper to replace, should the need occur.
A little 2 ft. x 2 ft. skylight will be around $125; a 2 ft. x 4 ft. skylight runs about $200; and a large 4 ft. x 4 ft. skylight will be closer to $300. A venting (opening) skylight is about double the cost of a fixed skylight.
You probably want to center the skylights in your room, both for aesthetics and for even dispersal of the natural daylight. However, there are no structural reasons for centering them, so if the situation dictates, move the skylight off-center. For instance, you may want to keep sunlight off a particular area of the room--to protect houseplants or a piano. Or you may want to make sure extra light floods a certain area--say, a reading nook.
Those are the most important considerations when planning new skylights. In Part 3, we'll examine structural issues of skylight placement and begin to explore their actual construction.
Jim Mallery, a semi-retired journalist and onetime registered contractor, has extensive experience remodeling, repairing, and rebuilding homes.