# Do you put foil over windows that get afternoon sun? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [August 20, 2009, 3:00am UTC](https://boards.straightdope.com/t/do-you-put-foil-over-windows-that-get-afternoon-sun/507028 "2009-08-20T03:00:33Z")\ **Posts on this page:** 6\ **Page:** 2
**Author:** ![aruvqan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aruvqan/32/2891_2.png) [@aruvqan](https://boards.straightdope.com/u/aruvqan)\ **Post date:** [August 25, 2009, 9:45am UTC](https://boards.straightdope.com/t/do-you-put-foil-over-windows-that-get-afternoon-sun/507028/21 "2009-08-25T09:45:02Z")
> [@Nava](#): > > Never heard of the practice, but I’m from Spain, where any house that hasn’t been built from flattened cans has “persianas,” built-in roll-down blinds; finding out that other countries don’t use them was a big cultural shock for me (alternatively, my American coworkers had a big cultural shock seeing those in Mediterranean countries). All we need to do is roll them down. It also has the advantage of being something you can control as minutely as you want to: you can leave them up (with the curtains drawn if you have furniture that will be damaged by direct sunlight) in the winter, down in summer, down but with slits if you want a bit of light to come through… and you can roll and unroll them as many times as needed, it’s a lot more controllable than any sort of films. ? I went and googled persianas, and got a page that when translated makes them the equivalent of our american venetian blind … almost every property i have rented and at least 30$ of the people I know use venetian blinds, though ours tend to be internal vice external and made of plastic or wood …[persianas](http://translate.google.com/translate?hl=en&sl=es&u=http://es.wikipedia.org/wiki/Persiana&ei=_rGTStCnF5G9lAeCt6HADA&sa=X&oi=translate&resnum=2&ct=result&prev=/search%3Fq%3Dpersianas%26hl%3Den%26client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official%26hs%3Dzxs) ---
**Author:** ![Nava](https://avatars.discourse-cdn.com/v4/letter/n/da6949/32.png) [@Nava](https://boards.straightdope.com/u/Nava)\ **Post date:** [August 25, 2009, 2:10pm UTC](https://boards.straightdope.com/t/do-you-put-foil-over-windows-that-get-afternoon-sun/507028/22 "2009-08-25T14:10:44Z")
Hell no. [These](http://www.persianas.tk/tk2/enrollables/aluminio_standard.html) are the ones I was talking about, in aluminum or wood. In that same company’s webpage you can find venetian blinds (which in Spain are used only by hotels from foreign chains) and the old-fashioned ones that were used before people figured out how to build them into the house (these folks call them “alicantinas,” I’m used to “enrollables”). Venetian blinds are a lot less efficient, both for light and insulation. Wood persianas are best for insulation, but aluminum ones are lighter (so better for children and old folk). ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [August 25, 2009, 4:39pm UTC](https://boards.straightdope.com/t/do-you-put-foil-over-windows-that-get-afternoon-sun/507028/23 "2009-08-25T16:39:48Z")
Nava they would be mini blinds in the USA and are widely used. At least if the page you posted shows the correct pictures. Every single window in our house has aluminum ones. No shadows at night showing the neighbors what your up to and they are better for sun blocking. ---
**Author:** ![Mahna\_Mahna](https://avatars.discourse-cdn.com/v4/letter/m/e47c2d/32.png) [@Mahna\_Mahna](https://boards.straightdope.com/u/Mahna_Mahna)\ **Post date:** [August 25, 2009, 5:19pm UTC](https://boards.straightdope.com/t/do-you-put-foil-over-windows-that-get-afternoon-sun/507028/24 "2009-08-25T17:19:56Z")
Actually, what **Nava** is referring to is something quite different from a mini blind. I’ve mostly seen them in Southern European countries like Spain and Portugal, and occasionally here in Canada in homes built by families who moved here from those regions. They’re quite common over in Southern Europe, though, as they do a great job of blocking the blinding mid-day sun (particularly handy for siesta time) and help keep older homes cooler in the absence of central air. Imagine the bastard child of a garage door and a mini-blind, and that might give you an idea of what she’s describing. I believe in North America they’d be called a roll shutter or something similar? ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [August 25, 2009, 5:48pm UTC](https://boards.straightdope.com/t/do-you-put-foil-over-windows-that-get-afternoon-sun/507028/25 "2009-08-25T17:48:02Z")
Ok think on a larger scale. Gotcha. ---
**Author:** ![Nava](https://avatars.discourse-cdn.com/v4/letter/n/da6949/32.png) [@Nava](https://boards.straightdope.com/u/Nava)\ **Post date:** [August 25, 2009, 5:55pm UTC](https://boards.straightdope.com/t/do-you-put-foil-over-windows-that-get-afternoon-sun/507028/26 "2009-08-25T17:55:31Z")
Thank you, **Mahna Mahna** [Previous page](https://boards.straightdope.com/t/do-you-put-foil-over-windows-that-get-afternoon-sun/507028.md?page=1)