With the 3M indoor window insulator kit, you can lower your heating bills during the winter and make your home more energy-efficient. Part of 3M's line of energy-saving products, this kit includes window insulation film and a roll of double-sided mounting tape to create an airtight seal. Stretching the film removes wrinkles for a transparent view. This version of the 3M indoor window insulator kit enables you to insulate five 3-foot-by-5-foot windows.

2141W Indoor Window Insulator Kit At a Glance: Window insulation film to insulate five 3-foot-by-5-foot windows Double-sided mounting tape with ready-to-peel liner Transparent, wrinkle-free fit Backed by a limited warranty

The 3M indoor window insulator kit provides an airtight seal to keep the heat in and the cold out (click to enlarge).

Keep the Heat In and the Cold Out
Made by 3M, this indoor window insulator kit contains window insulation film along with Scotch Window Film Tape to keep cold drafts out and warm air in. As a result, you can reduce your heating costs during the winter. The film shrinks tight around your window for a transparent, wrinkle-free fit and is made to reduce condensation and prevent frost build-up.

Double-Sided Mounting Tape for a Secure Seal
Included with this kit is a 1/2-inch-by-27-7/10-yard roll of 3M window film mounting tape to keep your insulation in place all season long. This double-sided tape seals off cracks and crevices, creates an airtight seal, and establishes a strong bond between the surface, the tape, and the insulation film, as recommended in ENERGY STAR's "Seal and Insulate" guidelines. Featuring a convenient, ready-to-peel liner, the tape adheres easily to a variety of surfaces and stays intact upon removal.

Simple, Fast Installation
Installing the window insulation is easy. You simply unfold the film and cut it to the width of the window, allowing an extra inch on all sides. Next, you firmly apply the mounting tape around the window frame and remove the paper liner. Then you apply the film to the tape, starting at the top of the window, and reposition and stretch the film to remove wrinkles. Finally, you use a blow dryer to remove any remaining wrinkles, then trim any excess film.

Made in the United States, and designed for indoor use only, this insulator kit can be used with aluminum, vinyl-clad, or painted or varnished wood molding, but it should not be applied to veneer paneling or Lauan mahogany molding. The film and tape should be removed from the window at the end of the season. The film measures 10 square yards, or 5.16 feet by 17.5 feet by 0.75 thousandths of an inch (H x W x D), and weighs 0.33 pounds.

What's in the Box
Window insulation film and one roll of mounting tape.

This insulator kit is easy to install, and a blow dryer enables you to remove wrinkles for a transparent view (click each to enlarge).

Included: (1) 5.16' x 17.5' film sheet, (2) rolls of tape, 1/2" x 27.7 yd

Insulates five 3' x 5' windows

Lowers heating costs and saves energy

Applies easily, shrinking tight, wrinkle-free and clear on glass

Increasing the R-value of single pane window by 90%

Average Customer Review: ( 139 customer reviews )
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I used these kits to seal drafty windows in an old building. It took a little over an hour to cover 4 windows. The temperature difference is dramatic and when the plastic has been well tightened and trimmed it isn't too noticable.

115 of 117 found the following review helpful:

Designed with Attention to DetailJan 22, 2008
By J. Small "A Bright"
It's smart for a couple reasons. Of course, the concept is simple: trap the air between the glass and the room and the air becomes the insulator. But it's all in the implementation and that's where this product shines. It uses double-sided tape that isn't so sticky that it will pull of paint when removed. Have to get that right and they did. The real attention to detail is the film material. When installed, it better not look tacky. So they formulated the material to shrink just enough to tighten it up to pull out the hard and soft wrinkles, but not pull away from the tape! Don't worry if the tape and the film lie on perpendicular planes. The film won't pull off when it shrinks. It's resilient enough not to overcome the film-to-tape adhesion. Again: brilliant.

It is also optically clear, not at all diffusive. That is another absolute must. I was simply amazed at how this product brings all this together into a cheap, effective solution to drafty old windows. Someone reviewed that the tape wouldn't stick to their window frame. Probably a surface prep issue. In my application the paint was new and firmly bonded. I even had strongly curved surfaces to tape over. I found that heating the tape with a hair dryer helped conform it to those surfaces. Directions don't address that issue and for flat surfaces it's not one. This is a great product!

63 of 66 found the following review helpful:

Great product, easy to installFeb 11, 2007
By Jen McClurg
I've spent the first part of this winter suffering because of drafty windows in the bedrooms of my new (old) home. I found this insulation kit from 3M, ordered it on Monday and it arrived on Thursday! In about 1 hour I had 4 windows sealed. I found it simple and straightforward to follow the instructions and it worked exactly as described. It's noticeably warmer in my bedroom, and I haven't adjusted the thermostat.

One note however, there was only enough plastic to cover 4 windows, not 5, and my windows are almost exactly the size given on the label. It was okay though, I covered the 4 worst offenders so it wasn't that big a problem for me.

19 of 19 found the following review helpful:

Works well, but . . .Dec 11, 2009
By Richard L. Elias
I have used 3M and other brands of shrink film on windows in my 120 year old house. The only problem I have with the 3M product is that you really have to cut the film to size beforehand. If you try to put it up without cutting first, it's very unwieldy. That's why I prefer kits with 3 or 4 smaller pieces; they eliminate the need to pre-cut. This isn't an important objection, I suppose, but someone may need this advice! Another caveat: if you seal a window with a tight storm window on the outside, moisture can build up on the film and drip into the sill. I have been told that this can cause the sill to rot. I haven't had this problem; one advantage of a 120 year old house is that NOTHING is or can be air tight!

27 of 29 found the following review helpful:

First time installing - massive pain and took ages, but got the result in the end - horrific directions!Dec 30, 2010
By dom2114
We have 2 gigantic windows + a patio door in our living room. Did a lot of research and chose 3M given the positive comments on the double-sided tape vs. the cheaper Duck brand (Walmart) and Home Depot/Lowes equivalents.

First off, the instructions on the box were just awful. Going by these, our first attempt at installing was a disaster. Spent a hour trying to tuck the film into the nooks and crannies of the window/frame, putting tape everywhere and then blow-drying. Got absolutely nowhere and was 5 mins away from giving up and returning. What we didn't realize is that the film is not supposed to stick to the window/frame like shrink wrap, but create a barrier that covers the entire window cavity...perhaps my stupid mistake, but I had no idea!

Having calmed down and taken a break, we tried it again and had much more success. The only other thing is that I to keep the blow dryer as close to the film as humanly possible (but without touching) for the film to shrink and become tight. Worked in the end though and was tight as a drum.

Very happy with the result (although not as crystal clear as other reviewers have said), but would recommend youtube research and patience for first time installers like myself!

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