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  1. gusfhb | | #1

    I have in the past lived in a place with exterior rollup shades for that purpose and they seemed to do the job

  2. walta100 | | #2

    Looks like a good place to plant a maple tree.


    1. andy_ | | #14

      I was going to say the same thing but make a snarky comment about carbon offset being a secondary advantage.

  3. nynick | | #3

    Ever consider an awning?

    1. Expert Member
      MALCOLM TAYLOR | | #5


      An awning or brise soliel would be my first choice too. That allows you to still enjoy the view from the window throughout the day.

  4. scottperezfox | | #4

    I live in Phoenix, and a lot of people have "shade screens" that they install seasonally. These are like normal window screens (mainly used to keep insects out), in that they are not air-tight, but the shade screens are definitely a tighter weave. It's the equivalent of sunglasses — it darkens the window and blocks a lot of the energy from getting through. But it's tougher to see outside, and impossible to see in. They end up being a bit anti-social, if you take that meaning.

    That said, I don't personally have them. They sell the kits at Lowes, etc. but I just haven't gotten around to building 'em for my windows.

  5. johngfc | | #6

    We have 4, 8' wide, rollup sun shades mounted near the outside of our soffits (two on the S side, two on the west). They are _excellent_. They allow some light through, they shade the windows, and they shade the adjacent walls. These are extremely common in some parts of the world, and I've always wondered why they seem so uncommon in the US. If you have a view, a dark color obstructs the view less.

    External shades can be much better than internal blinds - they keep the sun and heat outside your house.

  6. AndyBower | | #7

    The air temperature increase in the west facing rooms is part of the discomfort factor. The other part is the radiative discomfort. The rooms feel uncomfortable partly because the wall is radiating infrared heat directly at you, so it feels like you are sitting in an oven.

    Shades will cut down on this effect as long as they shade a significant portion of the walls and windows.

  7. Cafferatak2 | | #8

    For a highly distilled quantitative analysis, there was a webinar last year that discussed a study out of University of British Columbia in Canada that discussed the impact of external shading:
    Skip forward to minute 40.
    The gist is that operable, adjustable sunshades work well. However I know from my parents experience that wind can be a problem with them.

  8. walta100 | | #9

    It is unfair to change the title of the thread and replace the question with a totaly different question!

    If you want to build some kind window awning with a solar panel please provide a drawing.


    1. andyfrog | | #10

      This might have been done by the GBA editors. It happens on other posts.

      1. andy_ | | #15

        Absolutely HATE when they do this. I don't know if it's an obsessive compulsive tick, an SEO thing, or controlling behavior, but it makes it harder to browse follow ups when the titles are changing. If they put a new title in parentheses it wouldn't be half bad, but changing what the original authors wrote is annoying!

        1. Expert Member
          Michael Maines | | #25

          The editors here do sometimes change the title, strictly for SEO reasons. I agree that it makes it hard to follow threads you're following but it's important for them to get eyeballs on the page--so we/they can help more people, and so to show advertisers the level of engagement to help them can keep the doors open. Sometimes a revised title is also more clear than the original. Leaving the original title in paratheses is a good idea!

    2. Deleted | | #11


  9. PAHighEffBldg | | #12

    We had the exact same scenario, but even worse since it was a south facing master/main bedroom. We added Coolaroo roll up shades to the office, master/main bedroom and family room triple wide windows and doors. They work great and are automated by a Somfy hub to go up and down at set times. Even better, they are powered by a little solar panel so no wiring or batteries. I ordered them from - I got the Sydney 5 Black which still allows you to easily see what is going on outside. It works better than the shades I have on the insides of the windows which just end up trapping the heat between the shade and the glass.

  10. qofmiwok | | #13

    This should be helpful.

    If you're trying to keep heat out:
    Dark colors absorb light which makes heat. So dark shades on the exterior are great because you can see through them AND the heat they create stays outside. But if dark shades are inside, they don't help cool much because they absorb the heat from the sun.

    So looking at this table. The best is black exterior, then white exterior, then white interior. But those are all pretty good. Black interior is terrible.

    Seeing the view Some are advocating black shades even on the interior because you can see your views more easily, which is true (see page 13) But the black really darkens the room a lot more because it absorbs more of the light as it passes through.

    I put some black exterior shades on the outside of my west windows (main living space) and they do an astonishing job of reflecting heat while still allowing great views. But I will be using white on the interiors of the remaining windows.

    1. tdbaugha | | #16

      What do the numbers on the right side represent? Gray colored has the lowest number.

    2. Deleted | | #22


  11. qofmiwok | | #17

    This solar heat gain (SHG) chart is for the Soltis 92 fabric from Serge Ferrari. It is
    comparing white vs. black fabric for an exterior and an interior application. The white color allows 31% SHG when used as an interior shade and drops to 20% for an exterior installation. The black color however allows 69% SHG on the interior but jumps to an amazing 14% performance once mounted on the exterior. This is due to the 91% absorbance, which dissipates into the atmosphere.

    1. Expert Member
      DCcontrarian | | #18

      On the interior wouldn't it just dissipate into the interior?

    2. tdbaugha | | #20

      So is the 0.12 SHG exterior shade gray in color?

  12. AC200 | | #19

    I'm interested to see what you come up with. I currently building a house with the same situation. I specified triple glazed windows with double LoE 366 coating for a low SHGC. Am also having three air supplies and a oversize 30 x 8 air return duct installed in the room.

    I'm hoping it will be enough to mitigate a large part of the heat gain problem.

    1. Deleted | | #21


      1. AC200 | | #23

        I just looked up my window glass specs and the SHGC is 0.19. Have you considered window films to lower your SHGC?

  13. walta100 | | #24

    Will adding tinted film on the glass risk damaging the seals between the glass and voiding the windows warranty?


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