Energy-Efficient Roofing: Does a Metal Roof Save Energy?

Energy-efficient roofing is mostly about one thing: how much of the sun’s heat ends up in your attic. On that front, a metal roof makes a real difference. In winter, it helps in a different way, and it’s worth being clear about what a roof can and can’t do.

Does a Metal Roof Help With Cooling?

Yes. Asphalt shingles absorb the sun’s heat and pass it down into the attic, which is why upstairs rooms can get so hot in summer. Metal reflects more of that heat away and releases what it does absorb more quickly.

The numbers back it up. In independent testing by the Florida Solar Energy Center, Classic’s Rustic aluminum shingle cut heat flow through the ceiling by about a third compared with asphalt shingles.

The design of the shingle helps too. Each shingle is fastened at the bottom and locks into the next one at the top, which leaves a small pocket of air inside the interlock. That pocket slows heat moving from the roof surface into your attic, even though the shingles themselves sit directly on the deck.

Does a Metal Roof Help With Heating?

Less directly. A roof doesn’t insulate your home; your attic insulation does that. What a metal roof does in winter is work well with good insulation and ventilation: it sheds snow, helps prevent ice dams and keeps the roof deck dry. If your goal is lower heating bills, attic insulation and ventilation matter more than any roofing material. Our post on roof ventilation explains why.

Colour Makes a Difference

Lighter colours reflect more heat than darker ones. If summer heat is your main concern, especially on a house with a large roof facing south or west, it’s worth weighing colour along with looks.

Are There Rebates for Metal Roofs?

Not usually. The ENERGY STAR program stopped certifying roofing products in 2022, so no metal roof carries an ENERGY STAR label today. Current Ontario home energy rebates also tend to cover insulation, windows and heating systems rather than the roof itself.

The good news is that replacing your roof is a natural time to upgrade your attic insulation too, and insulation is often eligible. Check the current Ontario programs before you start, since they change from year to year. We also offer financing to help spread out the cost of a new roof.