Only The Best Daylighting Insulation Can Let In Light, But Keep Cold Out

Skylights can only be a beneficial daylighting solution when they are designed and manufactured to avoid condensation or heat gain and loss. They should lower energy bills by lighting a building, not raise utility costs by affecting the building’s temperature – but that’s easier said than done. To achieve this, we focused on adding an insulating solution to our daylighting system to help building owners get the most ROI.


How Many Panes Should a Skylight Have?

The vast majority of skylights on the market today put only two panes of glass or plastic between the building’s interior and the elements. Considering the extreme temperatures in many regions in North America, more significant insulation can really improve skylights.

To better shield a building from the elements, our Whole Sky Dome uses a quad-pane system that consists of an outer dome, an inner dome, and two diffusers at the bottom. The quad-pane system is enclosed with an innovative insulated stainless steel housing, employing: a thick layer of rigid polyurethane foam, which has excellent insulation value.

What is a Thermal Break and Does it Protect From Condensation?

Typical skylights use a “thermal break,” which is a piece of plastic or rubber 1/16th of an inch thick. Thermal breaks are hardly sufficient insulators, leading to heat transfer and — if it’s cold outside and warm and humid inside — condensation. The typical solution has been to drill holes to let water escape, or use a drip channel to catch the runoff. But this doesn’t solve the root cause of the problem: the unacceptably poor R-value and U-value of a traditional thermal break.

What are R-Value and U-Value?

R-value rises as U-value goes down, and vice versa, in an inverse relationship. R-value measures an insulating barrier’s resistance to heat transfer. U-value, on the other hand, measures the rate of heat transfer; so a high U-value means high heat conduction. Either measurement is enough to see how one unit compares to others in the industry. The R-value of our Whole Sky Dome is 4.0 The U-value is 0.25. A typical industry skylight achieves an R-value of 1.2 and a U-value of 0.83.

On an equal area basis, the Whole Sky Dome therefore loses 70% less heat than a typical prismatic skylight over the course of a winter season. Since prismatic skylights are optically inefficient, they are made very large to compensate, leading to even greater heat losses for a given illumination level.

Skylights are supposed to illuminate, not cool or heat a building. Extra layers of protection and the quality and thickness of the insulating material contribute to a skylight that does not transfer much heat into or out of the building. Not only do superior materials and manufacturing prevent heat exchange, but they also prevent condensation, which is unacceptable inside a building. The aim of daylighting is to reduce energy costs while bringing the most optically efficient, UV-free light into buildings – and to get there, building owners should invest in well-designed and well-built daylighting solutions.

Connect With Us

11 Mount Vernon Avenue
Mount Vernon, OH 43050 
1-800-886-8847 (U.S.A Only)



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