Heat and sun blocking film for windows

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blackwhisker
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Heat and sun blocking film for windows

Post by blackwhisker »

I have large windows facing the sun. It gets really hot in my house on sunny days, even in the winter.

I heard there is something called heat and sun block films for windows. It can keep the house cooler and not blocking the light. Something like this:
https://www.3m.com/3M/en_US/p/d/b5005059011/

Anyone has information or experience with such products? Any pros and cons I should be aware of? Thank you.
brian91480
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Re: Heat and sun blocking film for windows

Post by brian91480 »

I have experience using this at a previous house that I lived in.

It's a pain to install the film correctly. If you don't install it perfectly, you will see lots of creases and reflect light as you are walking by. It's pretty annoying. I mostly learned to just live with it, but I knew that I wouldn't be at the house forever. When I sold the house, I removed the film because it would have been a detriment.

With that said... the product does work well. This might be one of the few times that it is worth it to pay a pro to install, assuming they can do it much better than you can. Especially if this is a house that you expect to live long-term in.

--- Brian

PS. Yes, the YouTube videos make it seem easy to install. It's not that easy!
Tom_T
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Re: Heat and sun blocking film for windows

Post by Tom_T »

Can confirm, it's not that easy to install. For windows, I decided to use honeycomb shades to keep the heat out in the afternoon sun. I do miss the film on my storm door - my front door gets hot, including the door handle. I may need to put it back on. Or see if there is a storm door with better glass.
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plannerman
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Re: Heat and sun blocking film for windows

Post by plannerman »

I just did it on south facing windows in FL. My predecessors had had it done maybe 20 years ago and the old film had lost its effectiveness. Removing the old film was a bigger chore than applying the new film. Plus 1 on the YouTube videos--they were very helpful. Glad I did it; it makes a big difference on the sun load.

plannerman
LittleMaggieMae
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Re: Heat and sun blocking film for windows

Post by LittleMaggieMae »

I have exterior storm windows and then 75 year old double hung windows.

I added the film that helps keep the heat from the sun out of my house to the windows on the southern side of my house.

I put the film on the interior side of the double hung windows. It does work really well. It was easy to install - but as noted - it can be difficult to get it to be perfect. Especially if you don't have a helper to help with the installation.

I have window treatments - curtains or blinds that hide my crappy job of getting the film on the windows. I even patched together pieces of the film on one window - but I'm the only one who knows it looks bad. The curtains or blinds hide the seams and bubbles and crinkles.

With the film I can leave my sheer curtains on year round or leave the blinds open most days during the summer without adding more heat to my house.

If you need your window to look flawless - I believe there are professionals who will install the film for you. Or maybe you and another person or two can work together to better get the film installed with fewer flaws.

I did mine by myself. And I'm pretty sure I could do a better dramatically better job if I had a "helper" - an extra set of hands. :)

Be aware of privacy issues... at night, with a light on inside, you will no longer be able to see out the window (it's reflective) - but anyone outside will be able to see in. I can watch my neighbors across the alley - when they are in their kitchen and I can see into their upstairs bedroom (well the ceiling fan and door frame - and their little kids when they use their bed as a trampoline :) ) They have tinted windows and no window treatments - I'm guessing because they do not realize it's easy to see into their home at night. :)
Last edited by LittleMaggieMae on Mon Mar 27, 2023 4:51 pm, edited 3 times in total.
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CenTexan
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Re: Heat and sun blocking film for windows

Post by CenTexan »

I have used film, self-installed, and it has been great. However, it is tricky to install - especially large pieces. You could do a large window in "stripes" and overlay edges, then come back with a VERY sharp Exacto knife and a straight edge, and after making the cut, fish out the back over-laid trimmed piece, then smooth it down. When the film is still wet, you can actually slide the pieces to abutt one another. Use a good new squeegee, btw. The resulting seam is almost invisible. If your window is a focal point of the room (no sheers, etc), I wouldn't do it (maybe hire someone).

A second option is to build an exterior screen with solar screening. It works really well, but again, if you don't have the skill to make a screen (frame, roller, etc) it might not look that great. The good thing about the solar screen (versus film) is that you can seasonally remove it, if you like.
delamer
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Re: Heat and sun blocking film for windows

Post by delamer »

We had solar film put on almost all of our windows by a firm that does sales and installation.

It has made a difference in terms of cooling the house, but we are talking a couple degrees. It also helped with glare from some large west-facing windows in our kitchen eating area.

We used the least blocking film available that they had to limit the change in appearance.
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walkabout
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Re: Heat and sun blocking film for windows

Post by walkabout »

I don’t know if it is still an issue, but it used to be the case that some films and some dual/triple panes were not compatible. Applying the film could cause the seals on the panes to fail over time. Film can also cause the glass to break. If you have dual/triple pane windows and their warranty is still valid, double check the terms to see if applying solar film will void the warranty.

Not trying to propagate scare tactics, but do your research before just jumping in and applying solar film.

Good luck!
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Svensk Anga
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Re: Heat and sun blocking film for windows

Post by Svensk Anga »

I installed myself a similar product in my Florida house 20 years ago. Installation was not difficult. However, it now has severely deteriorated to the point that it ought to be removed. It looks bad. I can't work up the motivation to redo it. I'm not so sure it did enough to be worth the effort.
stlrick
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Re: Heat and sun blocking film for windows

Post by stlrick »

We looked into this about 15 years ago and chose professionally-installed Huper Optik rather than 3M. Very happy with it. Remains as clear as when new.
abner kravitz
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Re: Heat and sun blocking film for windows

Post by abner kravitz »

I have it, it does help. Had it professionally installed by a 3M dealer. I personally wouldnt attempt it myself on large windows.
Topic Author
blackwhisker
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Re: Heat and sun blocking film for windows

Post by blackwhisker »

Thank you all for the helpful replies.
Mr. Rumples
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Re: Heat and sun blocking film for windows

Post by Mr. Rumples »

Yes, had it in CO. Got the idea when visiting the Governor's Mansion which has a south facing facade. I asked someone who worked there and used the same company. There is defiantly a skill in getting it on just right.https://nyackel.files.wordpress.com/200 ... esouth.jpg
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tortoise84
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Re: Heat and sun blocking film for windows

Post by tortoise84 »

I used this tint, which was on sale for $26 when I got it, but right now it's $44:
https://www.amazon.com/Gila-Platinum-Ad ... 000KKM8EG/

DIY installation is a little bit tricky, but for $26, I wasn't afraid to tear some pieces off and redo if there were creases or imperfections. Use lots of soap spray on the window, under the backing, and on both sides of the tint, and you'll eventually get the hang of it.

Halfway through tinting a South facing window, I checked the temperature of the carpet where the sun was shining on. The untinted section was 95F, and the tinted section was 85F, so it definitely made a difference.

Yes, as other people said, at night with the lights on inside, you'll only see a reflection looking out, while people outside can see in clearly. So you'll need to use blinds or curtains as well.
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enad
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Re: Heat and sun blocking film for windows

Post by enad »

We have sunscreens that we added to our windows which are 80% and 90% blocking and they will reduce the amount of heat on the windows. We also have plated shades on the inside and some windows have dual pleated shades. They help mostly with light. We have a roller between the shades and the glass in some rooms which cut down on both heat and light if we want to darken a particular room of the house that is in full sun. But in the end we installed roller shades on several windows and removed the sun screens on them since the earliest you can block the heat the better chance you will have. We also have low E dual pane windows but we live in the desert where the temps can be in the mid 120's in the summer/fall and in the low teens in the winter.

Our neighbors had the film but it didn't matter if they installed it or a professional did, it still bubbled up after a while.
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FrugalInvestor
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Re: Heat and sun blocking film for windows

Post by FrugalInvestor »

We have Low-e double pane windows and use exterior mounted 80% sunscreens on the south and west sides of the house. They not only block a lot of heat but also protect interior surfaces (flooring, furniture, cabinets, etc.) from fading and also help the glass seals last longer. We also like that they increase privacy, especially during the daytime. Using dark brown or black screens allows your eyes to focus on what's beyond the screen, so although not clear when looking out it is not nearly as intrusive as one might imagine.

I chose not to use heat blocking film because it can cause the window seals to fail prematurely and having glass replaced is very expensive.
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Bogle7
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Re: Heat and sun blocking film for windows

Post by Bogle7 »

We have 3M film. Professionally installed. Recommended.
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tortoise84
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Re: Heat and sun blocking film for windows

Post by tortoise84 »

So I've been looking into this and it appears that some window films qualify for the 30% Energy Efficient Home Improvement Tax Credit as an 'insulation' product (not as windows).

Sources:
International Window Film Association
https://iwfa.com/news/window-films-are- ... x-credits/

Madico
https://madico.com/blog/energy-savings/ ... ntial-film

Johnson Window Films, for original tax credit that expired in 2022
https://www.johnsonwindowfilms.com/deal ... CLE_ID=273

However, going off the IRS Fact Sheet 2022-40
Insulation materials or systems and air sealing materials or systems: must meet the criteria established by the International Energy Conservation Code (IECC) standard in effect at the start of the year that is two years prior to the year the materials or systems are placed in service. For example, materials or systems placed in service in 2025 must meet the criteria established by the IECC standard in effect on January 1, 2023, to qualify for the Energy Efficient Home Improvement Credit in 2025.
Also, for the tax credit on insulation/window film, it must be your principal residence, and labor costs are not included (material costs only).

So we need to reference IECC 2021 for:
- Climate zones: https://codes.iccsafe.org/content/IECC2 ... 03_SecR301
- Glazed fenestration Solar Heat Gain Coefficient (SHGC): https://codes.iccsafe.org/content/IECC2 ... ecR402.1.2

In climate zones 0-3 the SHGC is ≤ 0.25 and zone 4 except Marine is ≤ 0.40. If your product quotes Total Solar Energy Rejection, then SHGC = 1 - TSER.
Old Guy
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Re: Heat and sun blocking film for windows

Post by Old Guy »

3 M professionally installed on windows and skylights.
BuddyJet
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Re: Heat and sun blocking film for windows

Post by BuddyJet »

Another 3m professionally applied customer. Consider the reflectivity of the films before deciding.
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talzara
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Re: Heat and sun blocking film for windows

Post by talzara »

blackwhisker wrote: Mon Mar 27, 2023 4:14 pm I have large windows facing the sun. It gets really hot in my house on sunny days, even in the winter.

I heard there is something called heat and sun block films for windows. It can keep the house cooler and not blocking the light. Something like this:
https://www.3m.com/3M/en_US/p/d/b5005059011/

Anyone has information or experience with such products? Any pros and cons I should be aware of? Thank you.
Solar control window films do block light, but they try to block as little light as possible. The most effective window films can block more heat than visible light.

This 3M product is only really effective on single-paned windows. It is barely effective on double-paned windows. Look at the last column of the datasheet: https://multimedia.3m.com/mws/media/117 ... y-card.pdf

The visible light to solar heat gain ratio is a measure of differential rejection. If it is above 1, then it transmits more light than heat. If it is below 1, then it transmits more heat than light. Exterior window shades have a VL:SHG of exactly 1 because they block heat by blocking light.

For double-paned clear windows, PR70 film has a VL:SHG of 1.1. PR20 film has a VL:SHG of only 0.4!

The most efficient windows have low-E coatings applied to the interior surfaces of the glass, between the panes. This has to be done at the factory before the window is assembled. When you apply window film to an already-assembled window, you only have access to the exterior surfaces of the glass, and most window films are applied to surface 4. It doesn't work as well because the sunlight has already traveled through all four surfaces of the glass.
talzara
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Re: Heat and sun blocking film for windows

Post by talzara »

tortoise84 wrote: Mon Mar 27, 2023 6:25 pm I used this tint, which was on sale for $26 when I got it, but right now it's $44:
https://www.amazon.com/Gila-Platinum-Ad ... 000KKM8EG/
The OP did not ask about window tints. The OP asked about solar films that block heat without blocking light:
blackwhisker wrote: Mon Mar 27, 2023 4:14 pm I heard there is something called heat and sun block films for windows. It can keep the house cooler and not blocking the light.
Low-E coatings make it possible to block more heat than visible light, but low-E coatings are most effective when applied to the interior surface of the glass, between the panes. Low-E window films do not work as well because you can only apply them to the exterior surfaces of the glass.
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