What percentage reduction did you get in your power bill, compared to what you paid before installing the foil?
Aluminum foil on the windows during the summer - anyone tried this? Did you save any money on power?
I haven’t used foil, but I have used very thin sheets of Styrofoam to cover windows, with good results. I think this stuff is sold as insulation to be used behind vinyl siding, come in 4’x8’ sheets. I cut it to fit tightly into the window opening - no fasteners required - and boom! My house was dark, but it stayed cool and cut my cooling expenses by a large bit. I’d estimate a 30% savings.
The second summer I used the foam, I prettied it up by using hot glue to cover it with grasscloth that I’d found cheap at Goodwill. I’ve moved now, and have better/ newer windows, but I may still try it again.
Hm,that might be a good idea to do on some of our older windows over the winter. Our bedrooms are always so cold and you can feel it most in front of the windows, and the stupid heat shrink clear plastic sheets don’t seem to do much. Being bedrooms who cares if they are light from outside.
I never thought of doing this but it seems like a great idea. I haven’t measured, so I don’t have exact numbers, but I can tell you that our house stays significantly cooler on days when we leave the curtains closed in summer. (We don’t run our AC during the day.)
When I lived in the desert my bedroom windows faced west. I put foil on them to reflect the Summer sun. The house had a swamp cooler with a single outlet, in the hall. I’d angle the door so that the air would blow on the bed, and left the window open a few inches so the air would flow. It worked well enough, but the foil would rattle in the breeze.
This certainly works but you need to be careful that you aren’t then reflecting a ton of sunlight into your neighbor’s houses. Styrofoam or something else that doesn’t reflect light like aluminum foil might be a better choice.
I’ve used the plastic heat shrink sheets here many times, and they always completely cure the problem of drafts through a window. I have to wonder if you’re using them correctly - chances are very good that my winters are colder than yours. 
I’ve tinfoiled windows before, and I didn’t notice any reduction in power usage, but I did get a significant reduction in light and heat coming in that window. I assume when you’re talking about power reduction, you live someplace with A/C (I have never had A/C in a house).
We went to Home Depot and picked up some UV blocking window film. They sell different grades for how much sun/heat you want to block. We installed it in our daughter’s room first, and had such good results, we eventually did the whole house. I think we ended up saving about 20% on our power bill.
The best part about aluminum foil is that it blocks the government’s mind-control rays.
I grew up in the Buffalo weather belt and learned to use the stuff there… compared to southern tier Western NY, Eastern Connecticut doesn’t have winter. We just have really cheap crappy windows.
Well, sure, but you have to put it on ALL the windows, not just the ones on the sunny side.
If you like light, you can always try bubble wrap. I don’t know how anybody could keep it intact long enough to hang it on the windows, though. That stuff doesn’t last 5 minutes around here.
This thread is making me think of the movie Crumb. I might have to scout out a copy of that.
When I moved from the rural farm I grew up on to an apartment complex in suburban DC, there was a streetlight right outside my bedroom window. The day after my first night in the bedroom I put aluminum foil on the window to totally black it out.
I like to sleep dark.
A B&B I stayed in used sheets of clear acrylic, velcro, and ribbons to cover it. They put a velcro hook line all the way around the window, and the fuzz on the inside of the acrylic. Then the other side (inside room side) they glued on wide ribbon to hide all the velcro tape.
She said it did a great job of lowering the HVAC costs, and customers coul deasily remove it if they wanted fresh air.
On the side of the house with no view she had frosted it, to further cut down on heat gain. It was a spray-on frost (like for Hoilday decorating) and she just hosed it off in the Winter.