Frame vs Glass: Where Your Window Loses the Most Heat

If your home feels drafty in the winter or your energy bills keep climbing, your windows might be part of the problem. Even newer windows can lose heat — but where does it actually escape the most: the glass or the frame?

Let’s break it down.

The Glass

Most of the heat loss happens right through the glass. It’s the biggest surface area on a window, and glass by itself isn’t a good insulator.

If you have older single-pane windows, you’re basically letting warm air pass straight through in the winter and cold air in during the summer. Modern energy-efficient windows use double or triple panes with insulating gases like argon or krypton to slow that down.

Low-E coatings also make a big difference — they reflect heat back inside during the winter and keep solar heat out in the summer.

If your home still has older single-pane or uncoated double-pane glass, that’s probably where most of your heat is escaping.

The Frame

While the glass is the main culprit, the frame matters more than most people realize.

Aluminum frames are strong but conduct heat easily, which means warmth from inside your home travels right out. Vinyl, fiberglass, and wood frames insulate better and don’t transfer heat nearly as fast.

But the bigger issue comes from gaps or poor installation. If your frame isn’t sealed tightly or has started to shift over time, cold air can leak in even if your glass is high quality. That’s why proper installation is just as important as the window itself.

Which Loses More Heat?

In most Ohio homes, the glass is responsible for most of the heat loss. But the frame and how it’s sealed can make or break how well that window performs.

Think of it like this:

• The glass controls how much heat passes through.
• The frame controls how well your window keeps that heat in.

You need both working right to keep your home comfortable year-round.

What You Can Do

If your windows are drafty, fogging up, or just not keeping your home warm, it might be time to look into window replacement.

When you do, focus on:

• Energy-efficient glass (double or triple pane with Low-E coating)
• Insulated frames like vinyl, fiberglass, or wood
• Professional installation to make sure everything’s sealed properly

Upgrade with American Way Exteriors

At American Way Exteriors, we help homeowners across Ohio choose the right energy-efficient windows for their homes. Our team focuses on products that actually perform — and installations that last.

If you’re ready to stop losing heat through your windows, reach out today for a free consultation and find out what window replacement options make the most sense for your home.

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