Energy Saving Window Insulation





Introduction: Energy Saving Window Insulation

About: I'm a retired mechanical engineer, woodworker, boater, and inventor. Now I'm getting into wood turning, and have found that all my wood projects need not be flat and square.

I found a quick and effective way to insulate house windows during times of extreme hot or cold weather.  It is called “radiant barrier”, it is about 3/8” thick and comes in rolls of typically 24” wide. There are several suppliers and it is usually found in home centers. Since it has reflective foil on both sides bubble insulation inside, I found it works well on windows to reflect solar heat in summer or keep heat inside during cold winters. Of course since this covering is blocking all light, you will probably want to use it in extreme conditions, or in unused rooms.


Step 1: Cut and Apply to Windows (and Doors)

Materials are pretty simple.
Roll(s) of "radiant barrier" insulation from your local building supply or home center
Double stick tape, or

Cut panels to the size of the windows you want to insulate. Use your double stick tape to attach the panels to the window. You can do this to a whole door also, a lot of heat will come through a thin door that is exposed to full sunlight or cold.

Step 2: Enjoy the Warmth When You Get Back in the House



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    9 Discussions

    Thanks BtheBike.

    Yes, should help in both Winter and Summer. The only downside, of course, is that it will block your view out those sliding doors!

    Doing this right now , Late summer but HOT . Only 1/2 done with sliding doors and this stuff is cutting the heat out but at least 5 degrees F. Hope to see the same temp stability when winter cold kicks in . I actually get frost inside the doors.

    "Use your double stick tape to attach the panels to the OUTSIDE of the window."

    Why attach panels to the outside, wouldn't wind and rain be a problem? I would like to try this to block afternoon sun during the summer.

    3 replies

    I edited the Instructable to omit references to inside and outside. When I originally wrote this, I thought there might be a benefit to have the panels outside during hot weather to reflect sunlight before it passed through the glass. But that is not necessary, and more trouble than it is worth.

    Thanks for bringing me back to the real world.

    Yes, good question why DID I say outside of the window, and even put OUTSIDE in caps? In many homes it might not be easy to get to the outside of the window.

    I think you are correct, and I appreciate you looking at my Instructable and pointing out this error. I will correct the Instructable unless I come up with a reason why I said "OUTSIDE".


    Thanks, Arizzotti.

    Cheap, easy ideas are often the best.

    I had not looked at that Instructable for a long time. Gee, my workbench was so clean and neat back then.

    Looked at your Instructable on insulating garage doors, great idea.

    I also use the 77 spray adhesive, good stuff. Also use double stick tape, of course, but recently found that carpet tape is often the best option.


    Bill, there is another bubble polyethylene sheet, far cheaper and translucid. It is not as effective, but allows light passing.

    Maybe putting it double you could reach a good insulating effect.