When I first started working on attics, I used to think insulation was all about fiberglass and foam. But over time, I realized how much of a difference a radiant barrier can make — especially in hot climates like Southern California.
A radiant barrier is basically a reflective layer installed under the roof. Instead of absorbing heat, it reflects it back out, reducing attic temperatures dramatically. I’ve seen second-story rooms drop by 10°F after installation.
I always tell homeowners this: If your AC runs non-stop during summer, it’s not just your windows — it’s your attic baking above you. A radiant barrier is one of the most cost-effective ways to fight that heat.
And no, it doesn’t replace insulation — it works with it. If you’re already upgrading your attic, you might as well do it right.
