What type have pepople used? I have cheap double pane windows, and am looking to save a $$ of heat loss without replacing the windows.

use the plastic film

Glass shops can usually make a storm panel and you can clip it to the wood trim. Remember you will have to store these in the summer, and be aware of condensation damage in the air space.

IAbout 15 yrs ago I  purchased the magnetic seals and bought plexiglas locally for inside storms.  The only thing that's not mentioned is that the plexiglas expands and contracts with temperature fluctuations. It took me a couple of weekends to do 13 windows.  I'd advise someone to do this on windows that you really don't plan on opening, as the panels are as large as the windows and have to be stored while the window is being "used".  The cost wasn't much, ( I had gotten bids from some local firms that I thought were unreasonable, I remember the cost for the 6 ft doorwall was $1,000.)but one of the great surprises was how much noise infiltration they prevented.  The cost savings were immediate and the house is more comfortable since they've been installed.

What did you put around their edges to make them air tight? And, how were they held in place so they could be removed? I have several windows I'd like to be able to cover during the winter and would appreciate advice.

I purchased plastic fittings, that had magnets. You could probably use clips, plexiglas and self sticking foam insulation.
I used plexiglas for looks, and light. And most of the windows aren't opened. Run a google search on magnetic storm windows.  The ones I got were magnatite.  I just checked a couple of weeks ago and the firm I bought them from doesn't list them anymore, but I know they're out there.  They were easy to install.  You just have to adhere to the measure twice philosophy. Used a hack saw, and a  great tape measure.  You do have to take care when you order the plexiglas, as I had them cut to size by a local firm.  The measurement has to be precise.  And the larger windows I have got thicker plexiglas...less bowing.  Like I said, I'm pleased.  Saved me a lot of money, both on my gas bill and on the installation.  And I didn't have to replace my old but functioning windows. And you can't tell that they're there.
 Oh, and I don't have to listen to my neighbor practice his rock lyrics anymore. (mid 40's, and he's looking to be the next Mick Jagger)  Lyrics are NOT family friendly...enough whining...hope this note gives you some insight.

The quandary of how to fix cold, leaky, inefficient windows without resorting to complete replacement has been difficult to address until recently when a double pane polycarbonate interior window insulation product was introduced to the market.  The R+ Window Insulator manufactured by Proactive Energy Concepts uses a unique self-sealing gasket to seal the insert into the window opening eliminating other fasteners and increasing the efficiency by 15-50% while providing more comfort than glass.   At 1/5 the cost of window replacement while turning a single pane window into a triple pane and a double pane window into a quad pane, not only are you saving money on the purchase, but getting a much better return on your investment than if you were to spend the extra money for ultra high efficiency windows.  Check them out at http://proactiveenergyconcepts.com/index.html under R+ Window Insulator tab.

Posted By GreenGuru on 02 May 2010 11:20 AM
The quandary of how to fix cold, leaky, inefficient windows without resorting to complete replacement has been difficult to address until recently when a double pane polycarbonate interior window insulation product was introduced to the market.  The R+ Window Insulator manufactured by Proactive Energy Concepts uses a unique self-sealing gasket to seal the insert into the window opening eliminating other fasteners and increasing the efficiency by 15-50% while providing more comfort than glass.   At 1/5 the cost of window replacement while turning a single pane window into a triple pane and a double pane window into a quad pane, not only are you saving money on the purchase, but getting a much better return on your investment than if you were to spend the extra money for ultra high efficiency windows.  Check them out at http://proactiveenergyconcepts.com/index.html under R+ Window Insulator tab.

Looked at the site and they lost me when they reported a 30-60% savings on heating.

I am the owner of ProActive Energy Concepts makers of the R+ Window Insulators.
We must not have the current web site for you. we are located at www.proactiveenergyconcepts.com or www.rpluswindow.com
I must apologize for my ignorance of where we state a 30 to 60 percent savings on heating I was not able to find it.
we have saved people more than that because of historical windows etc. but I try to stay relevant to the market saying 15 to 40% savings.
we are changing the window insulation market nationwide and would love the opportunity to have you call us to go over our product.
My name is Kevin Pearson
BTW glass has a different effect than Polycarbonate.
we normally have your interior temp with in a couple of degrees from the wall when we insulate. not 20 30 40 deg different.
Normal storm windows don't even come close to our performance.
drop me a line I am on the site under about us and contact us.
thanks for all you do in the real green world.
Kev.

Kevin

I folllowe the link posted about and followed the video link on your webiste. Is that you being interviewed? The following was cut and pasted from the summary of your interview.

Interview Highlights:

• Comfort Windows saves 30% to 60% on their heating bills.
• It's a product that goes over the windows.
• 500 franchises and expect to have 800 more.
• They are looking for more affiliates.
• Simple technology that few people.
• Their product is taking advantage of the.
• With the subsidies and incentives involved most people pay off the windows in a year and two months.
• They also make the house less noisy.
• This is a window that goes over a window.
• Windows can also go dark and you don't need curtains.

For the most part I have not seen that windows account for more than 30% of heating and cooling loads. If prior to installing your product windows accounted for 30% of heating and cooling then you windows must make the windows so they do not use any energy. Is that your claim? I would like to see the 3rd party data supporting your claim.

When a person sees a u factor of .24, a good quality replacement window , that translates in to a R value of 4.2. It takes a really expensive triple pane to get to an R11.

It's time manufacturers support their claims and for the typical house to which they are marketing too. The older homes these are marketed to are leaky and poorly insulated.

Hello GreenBuildingTalk,
I have to admit it is me in the interview.
and Yes we are a different sort of insulation than you will find made from glass.
if you look into the NFRC ratings used on all windows. they draw their information from the NFDB and model everything in one of several modeling software packages.
We used specs on our product from the NFDB and windows 5 to look into 16 popular window configurations to come up with our specs.
that's what I will send you when you have a name.
On a published note I am claiming our product saved in the real world test of several homes. claims stating more than that but as my last post stated I would like to error on the side of practical for my claims.
We seal up to your drywall. that makes us unique to all other products.
We seal up the cracks, weep holes, frame conduction, thermal envelope, felt strips on sliders etc.
I would like to have fairness in advertising also. you can mention argon or krypton gas are warrantied for only 2 to 3 years by any manufacturer. (reminds me of the 2k disaster hype)
so please don't mention efficient glass with gas. they fail very quickly and all window people know this.
as for your statement that a U factor equals a R factor you are misstating what an R factor is.
it is not linear by any means and based on type of material, type of frame, type of install they all differ.
you will see in my specs that I take single pane windows (R1) and make them an (R7). Higher if the existing windows are "really good"
I simply add two more layers of air between you and the out side.
if I may ask on the energy savings of buildings from fenestration do they throw out the highs and lows to come up with averaging statements like 30% as a standard. (I made a statement based on my findings not on averages) and I forgot to include a disclaimer.

I have recently preformed some real world thermal tests on double paned argon gas low e windows and when my window went in it changed the signature from several deg below the temp of the walls to several deg above the temp of the walls.

My over sight in my enthusiasm at a trade show mentioned hundreds of franchises. We have access to 507 if needed through the Glass Doctor. and we are starting to roll out nationally.
As to the ACORE video I do save people 30 to 60 percent. (some) and I will never mention it again in publications or live for I have found a common intolerance from the green washing going on everywhere around us. my statement is simple we save you from 15 to 40 % on your heating and cooling costs. I am sure you've witnessed a blower door test on triple pane windows and have seen the seals fail. mine seal those also. (in houses where green is the highest priority)
and yes we are looking for people to sell to an amazing market with our patented products.
I would love to chat drop me a line.
Kevin.

Kevin, I have been following this thread with some interest. I would caution you in your zeal. The audience here is educated and informed, and while I am sure you are quite excited about your product the people who read this will question your claims. Your statement that U factor and R factor or VALUE are not equal is also misleading they are related and correlative. U factor is the measurement of heat flow through a system and R factor is the inverse or resistance to heat flow through a system. they ARE DIRECT INVERSES OF EACH OTHER. R value was developed to help consumers understand what they were buying, a higher R number is better vs a lower U value being better. Of course they are both material and system dependent. That said having taken a look at your product literature and marketing info I am quite sure that you have seen real world gains in the performance of the buildings you tested, you are adding layers of insulative material and have sealed airspaces. Therein lies my first major concern. While it is not very hard at all to make a gain on a single pane window your claim of moving from an R-factor of 1 to 7 is a tough pill to swallow. While I do understand that glass has a very different conductivity than PC (or any other plastic) I cannot see how you are getting to that result. If you add your system to a single pane window and calculate for just center of glass numbers, you go from an R value of 1.025 to 3.039 that is if you are calculating in btu/ft^2/degf/hr in SI units it would be something like .17 to .55. I get the above result using a standard air gap of .5 for both gas layers. Air has an optimum gap of around .6 inches and then U factor and inversely R factor degrade as a result of increased or decreased gap size. I use only the center of glass numbers as an illustration that removes the things like air leaks from the picture. Again here is another issue. If we are talking whole window numbers than getting from 1 to 7 is even harder as the center of glass numbers are going to be higher, once thermal shorts like spacers or seals are introduced. Now this may be where your product makes real huge savings as a leaky window really under perform, yet those types of increases are going to be even harder to achieve, but again this would not raise the overall insulative value of the window it would only keep those numbers from being degraded by quite so much. Finally I will state my disclaimer. If you can show me how to either install one of your systems and realize these types of gains ( I can perform both U factor and SHGC testing myself) or can show me using LBNL's windows 5 how to get these numbers I will retract my challenges. I can be reached at [email protected].