Cheap DIY Solar window tint

[bennelson]

Hi everyone,

At my house, we have had a heat wave the last couple of weeks. About 95 degrees every day.

I have shades on the south-facing windows that I keep down to keep the hot sunlight out. However, I also have two large skylights, one in the kitchen (up real high, vaulted ceiling) and one in the upstairs bedroom.

Neither has any kind of blind on them. Both face west, and get a LOT of light through them the entire afternoon.

Special blinds for these types of skylights get expensive fast, and I just wanted a cheap, quick fix.

Digging through my camping equipment, I found I had a "space blanket". Those are thin sheets of folded plastic with a reflective silver surface. I unfolded the space blanket, and pinned it up against the upstairs skylight with a couple bits of tape. Then I trimmed off the extra with a razor blade against the glass.

After that, I filled a spray bottle with water, pulled back the space blanket, and spritzed a mist in there. Pressed the blanket against the glass, and sort of squeegeed with my hands from the middle to the outside.

The space blanket sticks right on the glass!

The other thing to keep in mind is that the space blanket IS NOT opaque! Rather, it's almost like a really dark mirror tint. The window is now reflective AND much darker, but I can still see out through it!

My house should now stay cooler because of less solar energy coming in.
Not bad for just a few minutes time and use of materials I already had!

[Patrick]

Just make sure that it doesn't get so hot that it ruins your skylight.

[Daox]

Haha, pretty cool Ben. Yeah, its been pretty warm lately!

[Laurentiu]

nice maybe I can find some on eBay

[bennelson]

Ack!

The sunlight turned the tint mostly clear!!?!?


Seems like the sunlight somehow "burned away" the silver on much of the space blanket, leaving it to be little more than clear plastic stuck on my skylight!

Guess those things really are designed for single use only, and NOT as solar tinting!

Oh well, now we know!

[Nevyn]

I bet it was thermal breakdown moreso than sunshine.

[bennelson]

Well, whether it was UV or IR, it still made most of the film turn clear.

The space blanket material is also really thin, so it tears super-easy.

Here's a photo of the skylight - you can see how part is still silver, and part is clear (where you can see through to the sky and the tree).

The shreds hanging down are from me trying to gentry remove it.



Here's the photo of when I first put it up, just so you can compare the two.


I also put a small piece of the same material on a regular window downstairs. It doesn't seem to be showing any of the same degrading effects. That's a south-facing window, but I don't think it gets as much direct sunlight as the skylight does. I also wonder if the vertical window vs the 10/12 pitch of the skylight makes a difference?

[Laurentiu]

hmm...I wonder if it would have done that if you stuck it on the outside

I'm thinking what could have happened is a the thin foil melted itself because it essentially trapped the heat between the glass and the aluminum foil thus the temperature there probably increased to a very high value. On the outside, it would reflect the rays before the glass, thus keeping it cool.

As a side note , I did a small experiment one day, i put the sun-shade (plain, aluminium-bubble wrap folding type) on the outside of the glass-securing it with the wipers so it doesn't fly away- and in full sunlight the dash and the inside temp. seemed considerably cooler than regular. Of course there is the matter of someone swiping your sun-shade (.99c, but still..)

I also wonder if the vertical window vs the 10/12 pitch of the skylight makes a difference?

Looking at the the this picture, I'm thinking the skylight angle on your house probable maximized the solar power in the same way they place solar panels at certain angles. The only place where a 90 degree solar panel (like your window stuck solar blanket) would be the at the Poles.

Ideally , a stationary panel is tilted from the vertical at an angle of 90º minus your latitude to maximize sunlight capture

[mimosa]

One can use solar shades for the window which give a modern look to your room and also protect your interiors by absorbing heat and controlling the harsh glare of sunlight.

[Exalta-STA]

I did the same thing on my attic windows..I went to an auto tinting shop and asked if they had any leftover tint from previous jobs. Apparently they had a lot and where more than happy to get rid of it...

Well they were in irregular shapes but I just pieced them together till they covered the window

One thing though..when you get them tell the guys to sort and pile together the same percentage tint...having 20% tint on one side and 4o% on the other end doesn't look quite well ;-)