Eco-Saturday: Shrinkwrap your windows

Here’s a cheap, quick project you can do to cut your heating bills, no matter where you live: Seal your windows with plastic film.

According to the National Resources Defense Council, a smooth third of the heat loss in your home occurs through the windows, so anything you can do to prevent that is money in your pocket.

In the late ’70s, Mom stapled sheets of Frost-King plastic over the windows to seal out drafts. It wasn’t a bad approach, but somewhere along the line — maybe in the late ’80s or early ’90s? — somebody came along with a product that was a bit easier to work with, looked nicer and didn’t require the use of staples or tacks to install. This new product was a kind of thin, crystal-clear shrinkwrap you attached to the molding around the window with double-sided tape and then heated with a hairdryer to smooth it out and make it virtually invisible. The plastic film was thinner than the old stuff, but it also made a tighter seal, thanks to the tape around the edges.

Plastic film will run you $2 or less per window at most hardware stores, and it’s fairly quick and easy to install. It comes with instructions, but for all us visual learners, here’s a photo tutorial:

Unroll enough of the film to go across the width of the window, including the molding on either side, and stick it to the trim just above the top of the window. (If you don’t have trim on your windows, stick it to the wall.)

Stick a length of the double-sided tape along the molding on either side of the glass.

Peel off the protective paper to expose the adhesive on the front of the tape, run another strip of tape along the molding just below the window, and unfold the plastic, smoothing it against the tape at the edges.

Use a hairdryer to heat the plastic until the wrinkles smooth out.

Trim the bottom of the plastic with a utility knife.

The finished product will be barely noticeable.

By the way, that strange texture on my window panes is bubble wrap, which I installed last year, and which doubles the R-value of the glass. I posted instructions for bubble-wrapping your windows last November. A year later, all my bubble wrap is still up except for a couple of pieces Walter swiped off the window behind the couch, which I replaced before I installed the clear film the other night. (Cats, apparently, love playing with bubble wrap as much as humans do.)

After I put up the film, I installed one of my falsa-blanket shades over the window. With basically three layers of insulation sealing out the cold, I hope to see our gas bills drop quite a bit this winter.