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Lamilux skylights? Or something similar?

Zins | Posted in Energy Efficiency and Durability on

Rennovating a home. We’re going to replace 8 skylights in total, and as much as I’d like to lower that number my wife won’t let me. So the goal is to do the best I can while keeping all 8.

Lamilux seems to be the best option for efficiency and avoiding thermal bridging, but they’re crazy expensive. $2400-3200 per unit.

Velux triple panes land in the $500-700 range.

Most of these are going into a flat roof. It’ll be warm roof, probably 6″ of foam under the rubber. Spray foam under the deck around the rafters.

What are people doing in this situation? Are the lamilux skylights worth it for their high efficiency? Is there another maker I should consider?

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  1. [email protected] | | #1

    For pricing are you comparing apples to apples, Lamilux versus Velux flat roof skylight?
    Do you have the performance specs for each?

    IG units are most efficient when vertical, so when calculating window performance there is the assumption that the window is in fact vertical. As a window is tilted from vertical energy performance goes down, but I don't recall what being horizontal does to the performance.

    I do like the 3° tilt on one of the Lamilux designs, but I really like the domed glass on one of the Velux flat roof variations.

    When calculating window performance, there is the assumption that the window is vertical. As the window varies from vertical, for several reasons, energy performance goes down.

  2. Expert Member


    So roughly $4,800 vs $22,ooo? From a straight energy savings standpoint, the payback for upgrading to the Lamilux would be in the centuries.

    If it were a case of junk vs quality it might be worth it, but Velux are pretty good skylights.

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