If you have old single pane windows, and the sort insulation that went along with them, your wasting your time with window film. It will not provide any significant reduction in heat load. What you need is solid exterior awnings.

Look at the 3M applied films. You can probably order on Amazon.

Branson: Ironically, I spoke with gila film and they said they only recommend install on double pane windows.

Windows on Washington: However, the dealers who use 3m and Madico which are supposedly superior say they install on single pane all the time. I have to go through a dealer to buy these, they are not sold by the film only.

I can't understand why you could not just get a heat blocking reflective film and put it on single pane, even if it is the lower grade Gila.

Do you have storm windows? With them installed, it will help the heat considerably, and of course, if you have inside window coverings that you close when the sun is coming in the window.

These are the kind of windows I have throughout the house ...

Still cannot figure out why GILA films told me they are only made to work on double pane windows... I imagine the majority of residential users are single pane windows who cannot afford to upgrade all their house windows to double pane.

That doesn't sound correct. I thought I read somewhere not to put window film, at least the heavy tinted stuff on double pane insulated glass because it may cause too much heat build up between the glass. I don't see why it would be a problem for single layer glass. Have you checked out tinted film. Even light tint makes a difference.

Guilty if putting some one some double pane glass, hasn't been any issue, so far, about 8 years in a West facing window.

I spoke with installers and they said they only use the higher end ones on single pane such as 3M and Madico. Gila film is considered the lowest end. Problem for me is you cannot get those individually, you have to go through an installer who works with them exclusively. I will call around and see if I can get JUST the material but as of now it's certainly not straight forward.

I used it 25-30 years ago on a single pane storm window when I lived in Oklahoma. Large picture window w/ fixed glass. I put the film on the inside side of the storm window. Didn't cause any problem with the window & it did significantly cut the heat gain from that window.

Was easy to find then in that part of the country. Amazon does have 3 or 4 different brands, included Gila film.

Solar screens, solar shades or shade cloth on the outside would be preferable because they would help block the sun from ever hitting the glass.

I just looked and Home Depot has the Gila brand, too. It's even in stock at my smallish local Home Depot here in the Central Wisconsin!

https://www.homedepot.com/p/Gila-48-in-x-180-in-Titanium-Heat-Control-Window-Film-HRT481/100616386

Another option (or perhaps additionally) is a roll-down shade. I added this one below and it really helps. You can find it cheaper at HomeDepot though the color may be different. Comes in all kinds of sizes.

https://www.amazon.com/gp/product/B00IWMLEKI/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

The manufacturer's site for more info is:

https://www.coolaroousa.com/

Luckyblueeye - which one did you specifically use? Gila mirror window film? heat block? Privacy?

The mirror one, I love the look of it both inside and out. I measured, and cut some extra (an " or so) for easy application but lined up top and one side to the window frame so I didn't have to cut all 4 sides after it was placed on the window. Leave a tiny gap on the cut side to allow the moisture to escape. I didn't buy the specialty spray, just used water with a little bit of shampoo (not one with conditioner in it, straight shampoo). Spray the film and the window liberally and have plenty of paper towels close by to wipe off the excess. I didn't end up with any bubbles etc. Definitely use the tip regarding separating the film...put a little bit of tape diagonally in the corner, on both sides but don't let the tapes get stuck to each other...then pull the tapes out and away from each other...they will pull the film away from the liner. Good luck!