Skylights, How Many Do I Need?

There are multiple factors to consider when deciding how many skylights you want.

I have always encouraged natural lighting. Not only does it save money on your lighting bill it just feels good having natural light in the home.

Installing one or two skylights during the roofing process is a great time to do it. It ensures a good installation rather than retrofitting later. The benefits of natural lighting most people understand, but I get this question often, how many skylights do I need?  It depends on where they go and how large the room is? Does it also depend on how much light you want?

Tubular type skylights bring in light from a small acrylic dome most being about ten inches in diameter. The benefit is the silver-coated tube is highly reflective and really produces a lot of light. They are perfect for tight attic spaces and work great for a room about 100 square feet. Having a pair in a larger room is nice can provide a lot of light. The typical 2×4 sq. skylight lets in more light just because of its size and the flared openings in the room. I have one installed in my home and it lights up a 300 sq. foot room very nicely.

Now, having stuck my neck out for all of the skylight guys to chop off, let me say, in some cases, the midday can well exceed these numbers. Trees, cloudy days, upper stories, chimneys, mornings and evenings can also affect the performance of your skylight with less light than some claim. So without getting into the lumens, the fluxes and foot-candles, I stand by my numbers.

I have installed hundreds of skylights and have found they work the best when you avoid these:

1. Hips, Valleys Low Slope Roofs can cause flashing issues, which possibly mean leaks.
2. Chimneys shadows are distracting as the earth circles the sun during the day.
3.  Antennas with skylights below end up with a huge amount of bird droppings that look horrible.
4.  TV viewing is affected by the sun's glare from the skylight.
5. Larger skylights create some heat.

Have a question? AskARoofer.

Find your local roofing contractor in the RoofersCoffeeShop® Contractor Directory.