Jump to content

Covering windows with a heat reflecting substance


NimrodTheGoat

Recommended Posts

It is summer, and it is hot. Unfortunately, my window faces the west, and good Lord have mercy it is like a furnace in there. I have no proper ventilation, and the fan on my ceiling is... well, sad. Yes, sad.

 

Would covering my windows with a light reflecting substance also reduce the amount of heat felt in my room? If so, what can I cover my windows with.

 

Posted this a couple weeks late, event hough I have been meaning to do so, I haven't because I am lazy. Thanks in advance.

 

Edit: I wrote the title kind of wrong, you can't reflect heat :doh:

Edited by NimrodTheGoat
Link to comment
Share on other sites

Leaving curtains or blinds closed when the sun is directly on the windows will help a lot.

 

Ventilation is what you need though. A fan will just blow warm air around. You need to replace warm air with cooler, this can come from the outside or air con with an external heat dump.

Link to comment
Share on other sites

 

Edit: I wrote the title kind of wrong, you can't reflect heat :doh:

 

 

The sun's heat transfer to us is through radiation, and you can reflect that. What reaches us is mostly in the visible and IR, so mirrors will reflect it quite easily. (You can also "block" convection, and you can reduce conduction, e.g. with insulation.)

Link to comment
Share on other sites

Leaving curtains or blinds closed when the sun is directly on the windows will help a lot.

 

Ventilation is what you need though. A fan will just blow warm air around. You need to replace warm air with cooler, this can come from the outside or air con with an external heat dump.

A white lace-type drape might help a bit, not too dear and shouldn't attenuate the light level too much. I think intensity-wise it will reduce by about a half. i close my curtains on the sunny side to reduce the greenhouse effect.

Link to comment
Share on other sites

Is mylar just a trade name for that type of film? i thought it might be different to the stuff used to reflect some of the light off windows rather than all of it.

 

 

Yes, it's a trademarked name for BoPET polymer film. Most of the reflectiveness comes from aluminum deposited on it, and I think you can adjust the density to some extent.

Link to comment
Share on other sites

Can the stuff you mentioned above be acquired in a hardware store? If not, I think aluminum would suffice

 

 

Prompted by this thread, I just ordered some Gila brand covering (from a famous online portal that Wonder Woman might endorse) but it's in stores, too.

Link to comment
Share on other sites

Can the stuff you mentioned above be acquired in a hardware store? If not, I think aluminum would suffice

A flat white cloth sheet, or even white paper, would look better than crinkly, cooking foil aluminium and you'll still get some light.

 

Home Depot do the Gila stuff, Swansont mentioned, and it's called 'mirror privacy window film'. i think that's a common store in the US, isn't it?

 

http://www.homedepot.com/p/Gila-3-ft-x-15-ft-Mirror-Privacy-Window-Film-PRS361/100196546

Edited by StringJunky
Link to comment
Share on other sites

And it does work. I used to work in a lab with windows on two sides facing south and west. It was unbearably hot in summer until they put that semi-transparent film on the winds. After that, it was merely hot!


(They only did it because they had bought some expensive new electronic equipment that would not work in those temperatures. Not because of our comfort...)

Link to comment
Share on other sites

And it does work. I used to work in a lab with windows on two sides facing south and west. It was unbearably hot in summer until they put that semi-transparent film on the winds. After that, it was merely hot!

(They only did it because they had bought some expensive new electronic equipment that would not work in those temperatures. Not because of our comfort...)

 

 

Similar situation here. They put it on the office windows to cut down on the heating bill, but we only got AC in the lab because of failed equipment and having to re-align optics after a temperature excursion was costing us a person-week per event.

Link to comment
Share on other sites

Reflective mirrored windows (or foil) probably isn't the way to go... There was that high rise in London a few years back that had to install shading on it's windows because, being concaved and reflective, they were focusing the sun down to a small area in the street... melting car parts and causing discomfort to people. Like ants under a glass in the sun.

 

As suggested, blinds or curtains should help a lot. Don't they put blinds on the outside of the windows in seriously hot countries? I think so.

Link to comment
Share on other sites

Reflective mirrored windows (or foil) probably isn't the way to go... There was that high rise in London a few years back that had to install shading on it's windows because, being concaved and reflective, they were focusing the sun down to a small area in the street... melting car parts and causing discomfort to people. Like ants under a glass in the sun.

 

 

 

In London? I wouldn't have guessed

http://www.cnn.com/2013/09/03/world/europe/uk-london-building-melts-car/index.html

 

I've read about this happening at a resort that was further south (article mentions Las Vegas) and thus got a lot more sunshine (and the sun was higher in the sky), but it was also the whole building and not just one set of windows. And if the window is flat, it's not a problem.

Link to comment
Share on other sites

 

 

Similar situation here. They put it on the office windows to cut down on the heating bill, but we only got AC in the lab because of failed equipment and having to re-align optics after a temperature excursion was costing us a person-week per event.

 

I think it is common procedure. Instrument failure (even if it is not that terribly expensive, though it often is) tends to get kicked up to admin. Discomfort does not. Though I managed to get facility management to repair the temperature sensors in my office once I made the facility supervisor to sit in the room with over 40C and drink coffee with me.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.