Finally gave in and tried foam backer rod for my window gaps

I spent two winters stuffing fiberglass insulation into the gaps around my old single-pane windows. It never stayed put and I could still feel cold air seeping through. A guy at the hardware store told me to try foam backer rod instead, said it seals better and doesn't settle. I bought a roll of 1/2 inch rod for $8 and pushed it into the gaps with a putty knife, then caulked over it. That was six months ago and my utility bill dropped about $30 a month. Has anyone else had luck with this stuff or is there a better trick for old windows?

2 comments

2 Comments

margaret2347d ago

Oh, you bet I've tried this one. I did the exact same thing on my old farmhouse windows and it was a total game changer for the drafts. The key is making sure you push the rod in deep enough so the caulk has a good surface to stick to, but not so deep it just falls out.

dylan_thompson7d ago

Did you make sure to push it in until it was just below the surface? I found that if I left it too flush the caulk would just slide off after a few months. A little trick I picked up was to use a wooden paint stirrer to really jam that rod into the gap, especially in the corners where it likes to pop out. Also, something a lot of people miss is that you want to oversize the rod a bit. If your gap is a half inch, use a three-quarter inch rod so it compresses and stays put without falling out. I had to redo a couple of windows where I got the size wrong and it made a huge difference once I switched.