The Pros and Cons of Glass and Acrylic Skylights
Acrylic skylights were the standard skylights in the 1980’s, but in the early 2000’s companies, like the international company Velux, started mass producing glass skylights. The benefits of these newer glass skylights far outweigh the benefits from acrylic skylights.
Velux fixed skylight models are mass-produced for use around the globe, making them cheaper than acrylic skylights. However, custom glass skylights can cost more than custom acrylic skylights. The brand new solar or electric venting glass skylights are more expensive than fixed acrylic skylights.
Glass skylights have a near perfect transparency rating. Acrylic, by its nature, can add a wavy distortion to the view and are usually tinted bronze.
Glass has factory seals that have twenty year warranties against failure by the manufacturers. Acrylic needs to expand and contract from thermal expansion and this wears out the gaskets that hold the acrylic dome in its frame. Acrylic will yellow and get brittle over time.
Tempered glass tends to survive punishment better than acrylic. Although tempered glass needs to have its edges protected inside a sturdy frame, they survive most hailstorms and come with a 10 year hail proof warranty. Acrylic will not hold the same weight as glass can—think snow load, and is easily broken by hail.
Acrylic skylights use 1980’s design technology. The better ones will have a thermal break (which separates the interior and exterior thermally) in the aluminum frames. However glass has much better thermal insulation standard in every skylight and comes sealed with argon gas between the glass panes for improved insulation.
Manufacturers of acrylic aluminum-framed skylights drill holes in their condensation gutters to allow the water to weep out. However this lets cold air and causes condensation. Glass skylights are sealed with 21st century technology to prevent heat & cold transfers and condensation.
Glass is flat low to the roof, giving a streamlined look. Acrylic skylights are domed and stand out and look out-dated.
Glass is better insulated, and reduces unwanted outside noise by up to 50% less than an acrylic skylight.
Velux skylights come with Neat® glass coating to keep your skylight cleaner longer, leaving the surface virtually spotless. Acrylic requires regular cleaning and care to ensure long-term usability.
In our opinion from thirty-six years of experience, glass skylights are better, and what we always recommend to our customers.
2 thoughts on “The Differences Between Glass and Acrylic Skylights”
I have an mid 80s house with three 26x26in (edge to edge outside measurements) skylights that need replacing, for a DIYer do they make the glass kits that you can put on top of the existing metal frame? Also i cannot find original matching 2 piece acrylic dome to replace the old ones either. Also my domes are not like the picture above my domes have the acrylic hang over edges not flat. And I’m located in riverside county California, Any thought thanks
I recommend using the Velux Dealer Locator.
A Velux FCM replacement should be very cost effective and easy to install if you’re comfortable on a roof. You’ll love it!