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Lisa_Tom | Posted in Green Products and Materials on

Is there an energy efficient skylight? I was thinking about a unidirectional skylight (e.g. lean-to, sawtooth) that only faces one direction for whichever use I want to use it for whether it be daylighting or passive solar. However, no one makes these that I can find in the U.S. The skylights would of course have glass only on one side or in one direction. Most companies that say they do custom are B.S. ers. Most of them can’t conceive of puttling glass on only one surface and blocking off the other. Anyway, I am no expert either so ………..???anyone? Thanks

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  1. GBA Editor
    Martin Holladay | | #1

    Most conventional skylights -- that is, skylights with flat (co-planar) glazing -- are what you call "unidirectional." The only type that aren't are cheap units with dome-shaped plastic glazing.

    If you install a skylight parallel to the plane of the roof slope, it will face the same direction as the roof slope in which it is installed. A skylight installed in a roof slope that faces north will also face north.

    If you install skylights in a flat or low-slope roof, you can build high curbs and then you can install the skylights to face any direction you want, at any angle you want.

  2. user-659915 | | #2

    Lisa, you need to expect to explain your concept more clearly, perhaps with a sketch or a photograph of a similar installation. I suspect what you have in mind is more complex than what is usually called a skylight.

  3. Expert Member
    ARMANDO COBO | | #3

    Just in case you haven’t check these manufacturers:Renaissance Conservatories,, or Velux Residential or Commercial skylights, They build custom skylights.

  4. sgeco | | #4

    skylights are already energy efficient if your purpose is to lighten up dark spaces in your house without using artificial lighting. What type of roof do you have? If you we're looking for skylights, there are many types: roof windows, unit skylights, tubular daylighting devices (TDDs), sloped glazing

  5. Expert Member
    Dana Dorsett | | #5

    Aerogel-insulated skylights suitable for residential apps (with polycarbonate glazing) are now available that r about U0.22, eg:

    The aerogel itself acts as a diffuser, providing nearly shadow-free daylighting compared to clear-glazed skylights.

    There are commercial versions out there that run about U0.1 or even lower, but SFAIK they're all full-custom and quite expensive unless you're putting in a lot of square footage.

  6. Lisa_Tom | | #6

    Here is the idea I am talking about. I need one curb-ready because has to retrofit onto one of those pre-fab aluminum/vinyl patio room kits with metal/foam roof. See attached photo for saw tooth skylight or some combination of sawtooth and monitor with south an/or north exposure. Hope this helps. I have contacted velux without luck. Other manufacturers are too far away (I am in California) thus shipping is high. Thanks for your help.

  7. GBA Editor
    Martin Holladay | | #7

    The vertical glass units in your sketches are called windows, not skylights. Any window manufacturer should be able to help you.

    If you want to install glass in a sloped roof, you'll need a skylight. Again, any skylight manufacturer (including Velux) can help you.

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