3 Cracked or Broken

Aging acrylic skylights are at risk of cracking or breaking.

Over time, acrylic materials lose the compounds that make them flexible, thus becoming brittle and susceptible to cracking and breaking. In Colorado, where summer hail storms are common, brittle skylights are a real problem.

Don’t make this mistake.

One of the common “band-aid” repairs we see in an attempt to repair a leak is to apply caulk or sealant to the seam between the outer dome and the frame of the skylight. This is not a good idea.

What people fail to understand is that skylights expand under the heat of the sun and then contract during the cool nights. Restricting the movement between the dome and frame can cause an enormous  amount of stress. Something has to give, and it’s usually the dome. In extreme cases, it can actually break the corner welds of the frame itself!

stress crack 2
Stress cracks caused by expansion and contraction of brittle acrylic.


The best option is to contact a skylight specialist at the first sign of a leak. A proper repair addressing the issue causing the leak—instead of a band-aid approach—can often provide many additional years of trouble-free service.

If your dome is already cracked or broken—it’s time to replace the skylight. The odds are that age is a contributing factor and the many advances in technology will provide advantages in thermal efficiency and/or light quality.

Two excellent options would be Energy Star rated, flat glass Velux skylights or the Velux LuxGuard polycarbonate skylights. Both carry warranties against breakage by hail.

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