oldhousefreak, I mentioned in a thread last year that I was going to try a clear coating made by Top Secret; they told me in emails it would work on polycarbonate, and would provide some level of UV protection, although they were not able to specify how much protection. I did order the product, but I'm embarrassed to admit I have yet to apply it; an illness and a house renovation really messed up my plans. At this point, my roof and south panels are so yellowed I know it will no longer be a decent test for the product, so I really muffed my chance to learn much. I did quite a bit of internet research looking for such a product, and found very little. The folks at Top Secret admitted they had no knowledge of anyone using their products on greenhouses, so it's a guess at best as to how truly effective it would be. For what it's worth, the link to the product I have (still sitting in the can) is here: TS-100 1 part epoxy coating Sorry to not be of more help, maybe someone else has made more progress than I have. Sheri

The UV factor in the windows is primarily to reduce sunlight damage to whatever is inside. For heat reduction, you need IR - infrared reflection. The "titanium heat film" claims to reflect up to 72% of the IR. "At zenith, sunlight provides an irradiance of just over 1 kilowatt per square meter at sea level. Of this energy, 527 watts is infrared radiation, 445 watts is visible light, and 32 watts is ultraviolet radiation." Hope this helps.

Not film, but plastic, at least on the pantry window...after an attempt at the front parlor window. :( Bought plastic last fall, didn't notice until I went to cut some off that it was only 36" wide--unlike the rolls I bought there before! Anyway, it works on the normal windows, but this year I couldn't use the old plastic on the front, so I tried this new roll, and it wouldn't work to leave any overlap to allow taping on the sides; I had cut it to length, taped the top, and was trying the sides, but it was windy, so got the stapler to help and first one went in fine, but when I stretched the plastic to do the opposite side, it didn't quite reach, and the staple didn't come out, so I fired it at the far end of the porch to clear it, and stupid thing popped open, spewing staples all over the porch! Since the plastic was a tad too narrow, I took the piece down and used it on the pantry, where there was plenty of extra width! Got to buy a wider roll tomorrow, and look into the film to make interior storms--hope it's not too expensive, since I already have the wood. Projects are never as simple and easy as they seem with an old house, especially since technical devices seem to have it in for me like that guy on the old Twilight Zone episode! If I didn't use a manual razor, I'd fear one would come down the stairs trying to get me! :)

I used window film in California years ago and put it on my home in Virginia. I thought it was more beneficial in California where the heat was moderate (75 -80). In VA, our summer temps are regularly 90 to 95 degrees. The windows just bake in that heat. The film actually absorbs the heat but doesn't prevent it from entering the room. The air next to the window film is very hot. In my opinion, it is a good product to cut the UV. For heat control, I think it actually absorbs the heat making the window hotter than without the film. It is beneficial in transom windows that are very high and difficult to add a window shade. In a hot climate, I think the Low E glass is the best solution. My next best solution is solar shades or at least a pleated shade that stays closed during the heat of the day.