Glazing and heat gain
Two numbers on a glazing spec sheet tell you almost everything about how a skylight will perform in Austin heat.
What you'll learn
- What a low-E coating actually blocks, and what it does not
- What the SHGC number on a spec sheet means for your cooling bill
- Why double or triple-pane glass matters more in Texas than added clarity
- How to read a skylight energy label before buying or replacing one
Step by step
- Find the NFRC label or spec sheet for your current or proposed skylight glass.
- Locate the SHGC number, a lower number means less solar heat passes through the glass.
- Compare that against the U-factor, which measures overall heat loss and gain through the frame and glass.
- Ask whether the low-E coating sits on the inside or outside pane, placement changes performance in hot climates.
- Bring both numbers to your installer conversation so the glazing choice fits a south- or west-facing roof.
Safety note
Swapping skylight glazing on an existing frame is not a simple DIY glass swap. Use this to understand your options, then have a professional handle the replacement.
Rather have a pro handle it?
We match homeowners with experienced, insured local skylight crews across the Austin metro. You reach us directly, not a national call center.
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