How to Seal Against Drafts and Air Leaks

TOM: Well, if your home is like most, it has hundreds of small gaps that can add up to big energy losses. Here with a few tips to help us figure out how to seal the most common sources of drafts and leaks is Kevin O’Connor.

Hi, Kevin.

KEVIN: Hi, Tom.

TOM: So where do we begin?

KEVIN: Well, you know, there’s a lot of places that air can get into the house; so think about where it might come through. Weatherstrip your doors and your windows and don’t forget to caulk around your trim. You also don’t want to limit yourself to the penetrations that go between the inside and the outside of your house. Think about looking at the vertical gaps that lead up to the attic. And here’s a good tip: if you see dirty fiberglass batts, well that means you have got air movement. Think about using expanding foam because that can seal all these penetrations.

TOM: And speaking of fiberglass batts, let’s not forget about the insulation, right?

KEVIN: No, absolutely not. Insulation is designed to prevent heat loss or gain through conduction and that’s the movement of heat through a solid surface; whereas air sealing is designed to prevent heat loss or gain through convection and that’s the movement of air itself. Both are critical to maintaining an energy-efficient house.

And for more information, we’ve got lots of videos on ThisOldHouse.com that will show you how to seal the gaps and cracks around your house.

TOM: Great tip. Kevin O’Connor, thanks for stopping by the show.

KEVIN: Always great to be here.

LESLIE: Thanks, Kevin. I am feeling warmer already.