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I'm curious how well the window shrink wrap really works. I moved into an older house (1927) in Lincoln, Nebraska, this summer. It's all single pane windows with a window screen and a storm window, as well. We have about 20 windows, so I'm estimating a cost for shrinkwrapping to be about $50-$100 with a couple hours of labor, too. I also just think the plastic shrinkwrap looks a little ugly, but if it'll save me more than it costs to install, it might be worth it. I've found some research just saying to replace the windows, but that's not feasible right now.

  • You'll have to replace the windows eventually or bankrupt yourself the moment a strong winter arrives. – Mast Oct 21 at 11:52
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    There will certainly be an improvement in comfort, and a reduction in condensation. An important issue, however, is how well sealed the rest of the house is. On a house of that age you could very likely feel wind blowing through the gaps between the window frame and the wall, or even feel wind blowing through the wall itself. – Hot Licks Oct 21 at 12:25
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    @Mast, having lived in the Midwest for nearly 40 years, almost every winter is "strong". And in the past 10 years or so, they've just been getting worse, with "bomb cyclones" several times in the past 2-3 years and week(s) long -20 to -50F (or worse) windchills. And, yes, this is probably a major factor in why the previous owner moved. – computercarguy Oct 21 at 16:45
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    @BruceWayne I'm assuming they mean something like this homedepot.com/p/… - it's designed for windows. – TylerH Oct 21 at 20:36
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    Having done this in a house with horrible windows, I can share this tip. MY window would allow the wind to blow through them, causing a draft in the house. I have the plastic on the trim around the windows. The wind would come through the trim, making the edges of the plastic flap like a flag in the wind. Suggestion: If you have such trim, caulk around the edge to stop that draft. FYI: There is alos plastic you can put on the OUTSIDE of the windows. – Scottie H Oct 21 at 23:30
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You will almost certainly save $100 on your heating costs by using film, assuming you install it well and stop drafts through the window seals. It may also make the home feel more comfortable, which can be the primary benefit.

Also, properly installed film is virtually invisible. You hardly know it's there.

In my former home here in Minnesota we put the tape on the face of the casing, applied the film, shrunk it, then trimmed the edges close to the tape. My wife usually did the job and could do it in a few hours. It was a no-brainer for us even with storm windows over the single-pane double-hung units from the 1950s.

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    Totally agree with this. We did it in our house in Grand Rapids,Mi and were amazed at how the plastic bowed inward from the outside air trying to get in. +1 – JACK Oct 20 at 19:49
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    I also agree, I use it on my crappy windows here in Alaska and it makes a noticeable difference. Of coarse Minnesota is colder than Anchorage :) – Alaska Man Oct 20 at 19:52
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    Forget something as good as shrink wrap. I camped in a lodge with significant gaps in the doors and we stuffed our bed sheet into the door frame to reduce the air loss. It went from below freezing to tolerable levels. If you really want to test how good shrink wrap is, wrap one of your limbs in it for an hour and see how it feels. Just a simple single layer makes a MASSIVE difference. – Nelson Oct 21 at 3:42
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    Another way to feel that the difference is real: Before installing the wrapping, turn off heaters in a room with single-pane windows (but not in the rest of the house); leave it for a day, and it will be much colder than other rooms (especially near the windows). Then add the wrap, and it will rise to be closer to the temperature of other rooms. – Peter LeFanu Lumsdaine Oct 21 at 9:37
  • Yep, we did this in our 1976 home in southern Minnesota. The windows were, for the most part, double pane, but it still made a difference. – Hot Licks Oct 21 at 12:27
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Film in Nebraska would likely be worth it, at least for the worst offenders in terms of drafts.

A tight storm window can boost a single-pane's R-value from 0.9 to about 2.0, which is actually comparable to many double pane windows. Coated storm windows can also drastically lower emissivity (by 75%) over plain glass ones, which helps a lot aside from R-values. Those upgrades will pay for themselves, and reduce the need for additional seasonal measures like film.

An easy and cheap way to keep the house warmer and more efficient is to stop air leaks around windows; most importantly the frame seat and between double-hung panes. For this, you can use a variety of cheap materials, including ready-made products. Caulk around the frame, around the storm window seat, and anywhere else that can take caulk and flickers a flame held close-by. If you can get everything air-tight you likely won't need film.

Get creative. My grandma always used the leftover loop half from a long strip of hook and loop (velcro) to tighten up the seal between frames. I fixed my old mudroom window by injecting hot glue between the panes to build-up the face, using wax paper in front of the top pane so you can't see any glue through the bottom pane when open. You can even simply cram soggy toilet paper into the cracks with a credit card, a trick from my dorm days, which works very well until the window's opened next spring.

No matter what you do, the big money is in stopping drafts. If you have no drafts, film doesn't add a whole lot of value. If you see attached film bow or cave, it means you have leaky windows, which should get fixed regardless of using film or not. I would patch things up air-tight, and if needed, apply film only where still needed.

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    It may be worth noting that the cost savings going from R1 to R2 will be about comparable to the savings going from R2 to R10000. While a +1 improvement to a surface that starts out at R50 wouldn't be very big, a +1 improvement to something that's below R1 is huge. – supercat Oct 21 at 22:13
  • Even with zero drafts (which can and should be addressed separately and additionally with caulking) the "second pane" of plastic is a huge energy saver because it emulates a double pane window with an insulating layer of air between the panes. (The only difference is that the insulating effects of the film itself are negligible compared to a glass pane, but that doesn't change the insulating effect of the air gap). – Peter - Reinstate Monica Oct 23 at 14:58
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    But thumbs up to the "get creative" part. Use rolls of fabric or carpet on the inner windowsill and on the floor in front of doors. Use heavy curtains and tug them in on the inner windowsill or let them hang to the floor. – Peter - Reinstate Monica Oct 23 at 15:01
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Air has pretty good insulation value if you can stop it from convecting. If it convects, it transfers heat fairly efficiently.

Fiberglass and rock-wool matt rely on this - the point of the strands is to create boundary-layer effects that prevent the air from circulating. That's why compressing fiberglass makes it insulate worse.

Too wide a gap between window panes will allow convection. They find under 1" is a good gap.

So when applying films, that's the target to aim for. If it's your own house, feel free to get some 1x1 square stock (3/4 square, really) and build yourself some spacers.

Also, more layers help more.

Also, make sure your windows are tip-top and properly maintained. For instance I am very familiar with "drafty" Victorian windows. Turns out, they're not supposed to be that drafty, and aren't if properly maintained. But things like the brass edge seals and top/bottom felts tend to be deleted by landlords during maintenance.

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    Even with wider gaps, internal, sealed convection isn't nearly the problem that whole-wall convection and mixing is (when no film is used). Convection loss is minor compared to loss due to leakage. So for most situations, applying film over the casing is the best practical approach. You really want the tape laid on a surface perpendicular to the film so it doesn't pull off. – isherwood Oct 20 at 19:53
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Growing up in Iowa in the 80's and 90's, we would put plastic on our windows every year. I'm pretty sure they were all single pane windows, too, as it was an older farmhouse.

As a kid, I don't know how much it helped with the cost of heating, but I know that the rooms where we didn't do this were often unlivable. Many of these windows, especially the old wood frame ones, had nasty gaps where the seals were damaged or missing, so there were pretty good breezes coming through. Because we didn't have AC, we sometimes left this plastic on during the summer months.

We eventually added caulk where possible and fixed other problems when we could.

The real solution is to replace the old windows with new, insulated windows. You don't have to do it all at once. Replacing 1-3 windows a year will help a lot. You can either start with the main living rooms first or replace the worse windows first. Yes, this costs a lot of money, but it will pay off later. It'll help with cooling costs, too, so you'll be getting year round protection. Not only will it prevent air leaks, but it'll help keep UV from getting through, as some windows have a coating, tinting, or polarization to help with that.

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Southern Michigan here. It makes a huge difference on single pane windows and a somewhat noticeable difference on newly-installed, well-caulked double-paned windows. On windows that we don't open, we tend to just leave it in place all year round (like the single-paned windows behind my boss's desk at work). On windows we like to open, we end up forgetting about it most years (well-caulked 15-year-old-now double-paned windows).

When we were doing construction and weren't using part of the house, plastic sheets hanging in doorways makes a noticeable difference as well.

Thick curtains made out of say... blanket material can look nice if you're into it, and they add a lot to the insulation. You can stack the effects with cling-wrap, and the blanket curtains can be made larger than the window itself if you're getting a draft around the edges. Only downside is that you don't get the heat of the sun coming in, and of course you lose the natural lighting. I think we get more use out of the cling-wrap, though.

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  • I have just a double-layer of some cloth that I had laying around, and made a curtain between my kitchen & main section of the house. But I only use it in the summer, so the heat from the kitchen isn't adding to the load on the air conditioner. (One winter I sectioned off the kitchen from the addition on the back of the house, which is a separate zone ... but the pump for the baseboard heating seized up, and the pipe froze and burst ... so I do not do this over the winter any more) – Joe Oct 23 at 18:55
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Yes definitely.

It will act as a low quality storm window but will still provide an air space for the heat to build up a gradient in so slow the movement of heat out of the window to the environment.

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