Sunscreens with low-E windows

[chrisprickett]

A client asked me to research the following. I haven't been able to get a definitive answer. Anybody wanna take a crack at it?

"You were going to ask your expert on sun screens about an earlier comment that sun screens coupled with treated windows could actually hold in heat and raise your air conditioning bills rather than lower them. Once you've had a chance to check that, I'd sure appreciate it if you'd let me know what your expert says."

[Brian G]

I'd have to say it's possible, but definitively...who knows?

My understanding: Low-E's are supposed to reflect most of the heat (radiant heat) back towards whatever side it's coming from. If the heat's in, it holds it in. If the heat's out, it holds it out. More or less, anyway. That's coupled with the normal insulating properties of double glazing (mostly conductive resistance) to make a more energy efficient window (also available in triple-glass, weird gases, etc.).

All the sunscreens I've ever seen were black, which will absorb heat, even while providing "shade". So...if the sunscreen were absorbing heat while the window just behind it was reflecting most of it right back into the space between, I suppose the trapped heat might be able to overcome the insulating properties of the glazing and conduct heat into the house. It's not an unreasonable theory on it's face, but may not be accurate.

Good luck finding a hard answer to that one Chris.

Brian G.

[WILDWOMAN]

Hello everyone. I'd like to try to help. When installing sunscreens over new energy efficient windows you need to add a spacer, minimum 3/4" at every clip. The way we resolved this issue was to buy some pvc 3/4" X 3/4" cut into 2" pieces. We used doubled sided tape to install the pieces on the back of the screen at every clip. We had to install longer screws in the clips to make up for the new distance. Living in Az. we know heat. This process let the heat vent from around the sunscreen instead of pushing the heat into the glass. Since doing this our energy bills have dropped at least $15 a month. This process will even help older insulated windows by the letting the heat vent between the window and the screens.

[kurt]

Got a picture? I'd like to see it.

Also, we may have an award for someone resurrecting the oldest thread.

[BADAIR]

multi layers of sticky back velcro tape allows air gap & easy removal for window/screen cleaning of stationary or non tilt windows

mine have survived the 70mph+ storms that often move through N. TX