Interior storm windows

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SolarAndWood

Minister of Fire
Feb 3, 2008
6,788
Syracuse NY
I did cheap and cheerful window film last year and it had a much bigger effect than I thought it would. I have read Gary's section on interior storms and think that the acrylic solution makes a lot of sense for me as my windows don't have any trim around them yet and incorporating a single panel across the whole assembly would not cost much other than the cost of the acrylic. My first batch of windows are 26 that need sheets of 30-31 x 60-61 although the 60 would be a little less than ideal.

I have a few questions after doing some initial shopping:

  • First question and maybe a dumb one, if I am going to be enjoying the use of these for 50+ years, is Acrylic the right choice?
  • How thick of sheets should I be looking for? Leakage is probably an even bigger motivation for me than insulating value because of the site and number of operating windows.
  • Is all clear Acrylic equal? Seems like there is a huge price range for similar specs?
  • Does anyone have any experience with any vendors especially those that cut to size?
  • How big of a deal is shipping? Should I be limit my options to local or is this simply a best price decision?
Thanks much...any other feedback is much appreciated.
 
Don't really have an answer for you, as I was looking at a similar project last year as I have a screen porch that I cover the screens with vinyl each year to keep the wind/rain/snow off the porch. When I was looking at the acrylic sheets, I couldn't believe how costly they were....it almost was more economical just to buy a basic window for each opering vs fabricate my own plastic insert out of acrlic. I reall was stunned on how much each sheet cost...I think it would have worked out to almost $100 just for one piece of acrylic.

https://www.hearth.com/talk/threads/alternatives-to-plexiglass-finished-with-pic.39049/#post-39049

Good luck....nice to see you back on the board.
 
I reall was stunned on how much each sheet cost...I think it would have worked out to almost $100 just for one piece of acrylic.

Prices seem to be all over the place and volume seems to make a big difference. Current front runner on price is
.080"x48"x72" sheet


at 50 bucks a sheet but the game is young;) My window size doesn't lend itself very well to 4x8 sheets. So, I think it is going to be a matter of calling until I find the right deal with someone that has some oddball sheet size that either reduces the waste or they simply want to get rid of.
 
I v always thought interior insulated shutters could be very useful,could be foam inside. WHen used it would make windows as thermally efficient as a wall
 
S&W, you've got me wondering how much custom built double-glazed windows inserts would cost (just the glass, not the frame).
I built a custom fixed pane window to replace a door in our great room and ordered the glass in a custom size from a local glass company. This was later installed in a wooden window frame assembly I built. The cost was about $100 for the 3x5 ft.

I realize that sounds expensive but it should perform better than a single piece of acrylic, never yellow, and it wouldn't require building a frame for mounting. It would require only that some sort trim be installed to hold the glass in place.
 
Forum member Smokey the Bear (Pellet guru) has made his own out of 1x1's and 1x2's with clear plastic. A PM to him may yield a cheaper or more DIY approach?

I have done the window kits myself and have been blown away by the results.

Looking forward to this thread.
 
S&W, you've got me wondering how much custom built double-glazed windows inserts would cost (just the glass, not the frame).
I built a custom fixed pane window for to replace a door in our great room and ordered the glass in a custom size from a local glass company. This was later installed in a wooden window frame assembly I built. The cost was about $100 for the 3x5 ft.

I realize that sounds expensive but it should perform better than a single piece of acrylic, never yellow, and it wouldn't require building a frame for mounting. It would require only that some sort trim be installed to hold the glass in place.

I was wondering about that when I first saw the price of acrylic. The picture is poor but you can probably see that I have the room to trim the currently roughed out windows out in a way to integrate it. I would have to come up with a storage solution though as there are 40 windows on the windward side of the house where I want to do this. The windows on that side of the house generally get opened in the Spring and not shut until Fall.
 

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We'd have the same issue with storage too. We have 8 large windows in our great room that I'd like to insulate better.
In our case since we have casements, we pull store the screens in winter and install them in the spring. The interior storm windows could be installed in the same recess where the screens normally mount.
 
I've seen interior storms on a sun porch that swing up to the ceiling on a hinge. Might work for an informal decor....


Ehouse
 
I did cheap and cheerful window film last year and it had a much bigger effect than I thought it would. I have read Gary's section on interior storms and think that the acrylic solution makes a lot of sense for me as my windows don't have any trim around them yet and incorporating a single panel across the whole assembly would not cost much other than the cost of the acrylic. My first batch of windows are 26 that need sheets of 30-31 x 60-61 although the 60 would be a little less than ideal.

I have a few questions after doing some initial shopping:

  • First question and maybe a dumb one, if I am going to be enjoying the use of these for 50+ years, is Acrylic the right choice?
  • How thick of sheets should I be looking for? Leakage is probably an even bigger motivation for me than insulating value because of the site and number of operating windows.
  • Is all clear Acrylic equal? Seems like there is a huge price range for similar specs?
  • Does anyone have any experience with any vendors especially those that cut to size?
  • How big of a deal is shipping? Should I be limit my options to local or is this simply a best price decision?
Thanks much...any other feedback is much appreciated.

Hi,
I ended up ordering my Acrylic from Home Depot. They have a limited array of sizes in stock, but were willing to special order sheets of other sizes and thicknesses. They have a minimum order of each size of sheet, but for what you need, you would probably be over the minimum. Their prices were better than what I could get at local glass shops, and they did not charge for shipping as long as you picked it up at the local HD. Maybe worth trying them.

Shipping can be expensive, but I've found when ordering polycarbonate glazing that while local glass shops can get it and don't charge shipping, their prices are so much greater that I end up paying the shipping (and crating) and come out ahead with an online order. You definitely want to get shipping quotes for online orders as they are all over the map.

As near as I can remember the stuff I used was 0.08 inch thick. This works OK for the normal size windows (about 30 by 50 inches), but makes for a floppy install on larger windows. I think if I were doing it again, I'd go for 1/8 inch on regular windows and maybe 3/16ths on large windows.

This is one spec on Acrylic: http://www.builditsolar.com/References/Glazing/physicalpropertiesAcrylic.pdf

I believe that it is quite resistant to yellowing from UV -- my Acrylic storms go back to 2005 and they are still crystal clear.

I'm kind of inclined to think that one brand of Acrylic is about the same as another, but have no data to support that.

Cutting it takes a bit of care -- I supported it on both sides of the cut with 2 by 4's and then cut it with a fine tooth (metal cutting) blade in an electric sabre saw. If you go to slow, it tends to melt the plastic, and if you go to fast it tends to crack the plastic, so it takes some care -- but, not difficult if paying careful attention. They also make a tool that you can score the Acrylic with and then snap it over an edge -- I did not try that.

On storage, we just leave the larger (fixed) Acrylic storms in place all year. The smaller ones on opening windows just stow behind furniture in the same room they are used in.

Gary
 
I was wondering how polycarbonate (Lexan) would compare to acrylic for this application and came across some useful info on both.
http://www.hydrosight.com/technology/polycarbonate_vs_acrylic.php


Good comparison.
One thing they did not cover is that polycarbonate stands up to higher temperatures -- about 270F -- its fine for solar collector glazing.
Polycarbonate needs a manufacturer applied UV protective coating to be used for glazing, or it will yellow fairly quickly.

Seems like Acrylic is probably the best choice for inside storms with its long term clarity and lower price?

Gary
 
Seems like Acrylic is probably the best choice for inside storms with its long term clarity and lower price?
It would seem so.
 
Are you planning on getting some sort of system to make an airtight seal with the storms?

I've been looking into interior storms too. The magnetite.com website looks a bit dodgy but is probably what I'm looking for - they provide the steel and magnetic strips and you provide the acrylic. Anyone have any experience with them?

This website is also useful for those of you in the US: http://www.windowattachments.org/products/ Wish I could find one for Canaidia-land.
 
Thanks for all the feedback guys and I hadn't even thought of using my accounts at HD and 84 as a source. The other thing that occurred to me is that I could simply build the wall thick enough to mount two windows in it? I got a great deal on my windows because a detailer on a brick building renovation made a mistake on the width. I ended up building the house around them. This approach would make the glass the same, provide the solution for the seal and make the finish trim simpler. I don't have enough to do the whole house but could do the primary living space if I adjusted the window plan for the half of the house I haven't rebuilt yet. All of the secondary rooms could then get acrylic.

Its blowing pretty good this morning and I'm watching the plastic film I installed last week over the windows "breathe" in the gusts. This is a good thing to get right.
 
I did interior storms for my transom windows. They are 3 yr old Andersons. Everyone said I don't need them. I bought a single pane glass, slipped it in and then took some 1/2" x 3/4" pine strips to hold the glass in. I stained them and nailed them in with a brad nailer. It might not help heat loss but it sure did keep the moisture off the windows I didn't do. I later did the rest for 5 bucks a pane. Sure it helps heat loss too. I'm doing to do the stationary crank out windows too but they are 28 bucks for 26X56" glass.
 
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They are 3 yr old Andersons. Everyone said I don't need them.

I've been told the same thing. But, I'll tell you what, I burn a lot less wood with the plastic film up. Might not make that noticeable a difference in a typical house, but the effect in my house on my site is huge especially when its blowing.

How much does the second pane of glass affect the view through the window? Can you tell the glass is different or does it blend? The price is certainly right.
 
They are transoms so I don't look right into them. However I told my wife they were there and she never noticed. She is a very fussy woman to boot. I also forget they are there.
 
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