“My second floor is unbearable in the summer. The AC just can’t keep up.”
We get this call all the time. If that sounds familiar, you’re not alone—and the culprit might be right above your head: your attic. We’ll show you how you can tell and what you can do about it below!
Your Attic: A Solar-Powered Radiator
On a sunny day, your roof takes a beating. Shingles can reach 150–190°F under direct sun, and that heat doesn’t just sit on the surface. It radiates down into your attic, turning the space into a solar oven. In an uninsulated or poorly insulated attic, temperatures can soar to 130–160°F, even higher in some climates. Now think about this: your attic sits directly above your second floor. So what happens when it’s 150 degrees up there? It’s like parking a radiator on your ceiling and cranking it on full blast.
Why Your AC Can’t Keep Up
Most homes have HVAC systems that were never designed to overcome such intense heat loads from above. The result is a second floor that never really cools down, no matter how long your AC runs. Rooms feel stuffy, uncomfortable, and sometimes even humid despite the system working hard. And because of this constant effort, your AC runs almost continuously, which drives up your energy bills and wears out equipment faster.
If your HVAC ducts are in the attic, they’re likely sitting in that 150°F air. That means the cool air you’re paying for is heating up before it ever reaches your vents!
The Solution: Spray Foam Against the Roof Deck
Here’s the game-changer: applying closed-cell or open-cell spray foam insulation directly to your roof deck. This creates what’s called an unvented, conditioned attic. The results it can bring to your home are nothing short of incredible.
Instead of letting your attic reach extreme temperatures, it now stays within 10–15°F of your indoor living space. Heat transfer from the roof into the attic drops dramatically. And if you have ductwork up there, it suddenly operates in a climate-controlled space, with no more heat-soaked ducts robbing you of cool air. Because spray foam seals every gap, crack, and air leak, your HVAC only has to cool the house.
Spray Foam Drives Real Results
Homeowners who upgrade their attics with spray foam consistently tell us the same thing. Their second floors finally feel cooler, their AC runs far less, and their energy bills go down. On top of that, their HVAC systems tend to last longer because they’re no longer running around the clock. It’s not just an insulation upgrade: it’s a total building performance improvement.
Add Attic Insulation With Responsible House
If your second floor feels like a sauna in the summer, the problem isn’t your AC. The real culprit is your attic. By applying spray foam insulation to the underside of your roof deck, you can stop the sun from turning your home into a giant heat trap.
Want to know if spray foam is right for your home? Give us a call for a free attic assessment. We’ll help you take back your comfort—and your energy bill.
Stay cool,
William Drumeller
Certified Building Performance Analyst & Owner, Responsible House
