Repelling heat in your house

[BuccaneerBrad]

Here's my situation.   My bedroom is on the second floor of a two story house and faces west.   It has two large rectangular windows (about 6x3 feet).   I have modern blinds on my windows that I keep closed at all times, but even still, the sunlight shines in very strongly and heats up the room to practically unbearable levels almost every afternoon.

Any handy people on here who know a way to stop that heat from coming in?

[Tenshot13]

Solar curtains.  Ross or a TJ Max type store should have them if you need them cheap, works for me.

[Pappy13]

I'll second that. We have wooden shutters that do a tremendous job keeping the heat or cold out.

[Dolphster]

We live in Texas where the summer sun is just as bad as FL.   It was expensive, but we had "solar window screens" installed on the outside of every window.  Not only does it REALLY help with the air conditioning in the summer, but it also saves us a decent amount on our electric bill and they are dark enough that during the daytime, you can't see in the windows so it doesn't even matter if we leave the drapes/blinds open. 

[Dave Gray]

As I understand it, there are misconceptions about this kind of thing.

Once the heat gets in your home, it doesn't just leave.  ...so, if you had black curtains, the heat will come in and it stays there.  It might be hottest by the window and block the heat from seeping into the room as much as open windows, but ultimately, you're still paying to cool that with your A/C.  To really affect it, you either have to block it from coming it (like with tint) or reflect it (like with a mirror-like coating) on the back of blinds.

[CF DolFan]

As I understand it, there are misconceptions about this kind of thing.

Once the heat gets in your home, it doesn't just leave.  ...so, if you had black curtains, the heat will come in and it stays there.  It might be hottest by the window and block the heat from seeping into the room as much as open windows, but ultimately, you're still paying to cool that with your A/C.  To really affect it, you either have to block it from coming it (like with tint) or reflect it (like with a mirror-like coating) on the back of blinds.

This is true. We used to have a 12' slider in our family room with the same issue. We used to have room darkening curtains which blocked all light but it wasn't until we replaced it with double-pane, argon gas insulated that we noticed a difference in temperature. You can stand next to the window and not feel heat until you almost touch it. 

[MyGodWearsAHoodie]

Add an awning to shade the window.

[Dave Gray]

Add an awning to shade the window.

This is a very good suggestion, as well.  Simple, but the most effective option of all of the choices.

There is "keep the room cooler" and there is "save money on A/C cost".  They are related, but not exactly the same.

[Pappy13]

As I understand it, there are misconceptions about this kind of thing.

Once the heat gets in your home, it doesn't just leave.  ...so, if you had black curtains, the heat will come in and it stays there.  It might be hottest by the window and block the heat from seeping into the room as much as open windows, but ultimately, you're still paying to cool that with your A/C.  To really affect it, you either have to block it from coming it (like with tint) or reflect it (like with a mirror-like coating) on the back of blinds.

That might be true for curtain's, but it's not for the window shutters that I have. The wooden slats of our shudders don't heat up and radiate the heat into the room, the heat is trapped between the window and the shudders similar to how your walls work. Once the sun goes down that heat dissipates. Now I'm no scientist, but I can tell you there's a palpable difference between a room where the wooden slats are closed and one where they are open and let the sunlight in, it's not a scam. They don't completely stop the heat, but they make a big difference and they make a difference in a/c costs as well. This is a little different from curtains that are actually letting the heat into the room between the window and curtain. The shutters are enclosed within the window casing, all the heat is trapped in the window casing, it's not allowed into the room at all.

[MyGodWearsAHoodie]

As I understand it, there are misconceptions about this kind of thing.

Once the heat gets in your home, it doesn't just leave.  ...so, if you had black curtains, the heat will come in and it stays there.  It might be hottest by the window and block the heat from seeping into the room as much as open windows, but ultimately, you're still paying to cool that with your A/C.  To really affect it, you either have to block it from coming it (like with tint) or reflect it (like with a mirror-like coating) on the back of blinds.

While I have less experience with this than Floridians.  I doubt that is true based on personal experience of putting a cardboard sunblock in the front window of a parked car results in a noticeable cooler car.  The heat didn’t just build up between th cardboard and window and then spread into the car.

[masterfins]

Here's my situation.   My bedroom is on the second floor of a two story house and faces west.   It has two large rectangular windows (about 6x3 feet).   I have modern blinds on my windows that I keep closed at all times, but even still, the sunlight shines in very strongly and heats up the room to practically unbearable levels almost every afternoon.

Any handy people on here who know a way to stop that heat from coming in?

Is it just that bedroom, or the entire second floor that gets hot?  There probably is a lot of heat radiating through from the roof.  Also, heat rises, so heat generated downstairs rises to the upstairs.  In the summer on hot days the second floor of my house can easily be 20 degrees hotter, even with all blinds closed.

[BuccaneerBrad]

Is it just that bedroom, or the entire second floor that gets hot?  There probably is a lot of heat radiating through from the roof.  Also, heat rises, so heat generated downstairs rises to the upstairs.  In the summer on hot days the second floor of my house can easily be 20 degrees hotter, even with all blinds closed.

It's only my bedroom.   I go out into the upstairs hallway and the rest of the house is much much cooler

[Dave Gray]

Even non-reflective surfaces will reflect some UV.  So, wood blinds is better than nothing.  But you're still going to let in a lot of heat between the wood blinds and the glass window.  That heat will be trapped and may not fill the whole room, but it will dissipate into the room and you will have to pay to run your A/C to cool it.

If the blinds were reflective, it would be better.  But it would be even better to prevent the UV from coming in at all, like a reflective tint on the window itself or a physical barrier on the outside, like a shutter.

[Pappy13]

Even non-reflective surfaces will reflect some UV.  So, wood blinds is better than nothing.  But you're still going to let in a lot of heat between the wood blinds and the glass window.  That heat will be trapped and may not fill the whole room, but it will dissipate into the room and you will have to pay to run your A/C to cool it.

If the blinds were reflective, it would be better.  But it would be even better to prevent the UV from coming in at all, like a reflective tint on the window itself or a physical barrier on the outside, like a shutter.

Dave, I respectfully disagree with you. I think you are oversimplifying and generalizing. It's been shown that having wood blinds will decrease your a/c costs. Unless you have some type of proof these are ineffective, I'm skeptical of what you are saying. Now I'm not saying they are 100% effective, absolutely not, but it's been shown they will eliminate like 40% of the heat that would come in through the windows without the blinds. Yes, reflective tint and other methods also work, but none of these other methods are 100% effective, much lower in fact. It's a matter of cost versus effectiveness. Wood blinds work to reduce your a/c costs. Reflective coverings also work. I'm not sure how they compare on effectiveness, I think they are comparable but not really sure. I've been looking for some comparison but can't really find anything definitive online. I'm not a member of consumer reports, maybe someone can check that out. I'm not saying they are the most effective, but they do work. I'm not really sure how they fall on the cost versus effectiveness scale, but I think it's lot closer then you think if in fact they aren't higher. Everything that I have read says the choice is really not about energy efficiency but rather about privacy. If you want total privacy and get energy efficiency as a bonus wooden blinds work really well. If you are only concerned with energy efficiency but want to be able to see out and see in then go with the reflective coverings which allow for that. I'm assuming you could also double dip and do both and get the most energy efficient solution. Actually we have double pane windows filled with Argon gas I believe that also helps with energy efficiency. There's a lot of options out there, do your own research.

[Dave Gray]

Dave, I respectfully disagree with you. I think you are oversimplifying and generalizing. It's been shown that having wood blinds will decrease your a/c costs.

Correct.  Wood will decrease your a/c costs better than having nothing.  Any surface will reflect some U/V.  Wood is better than black blinds, for example.  Especially if the wood has some kind of shiny coating on it that would reflect even more light.

But if you reach behind your wooden blinds and the air is hot, that heat is in your house and your A/C will have to work to cool it as it seeps into the space...the heat doesn't just leave out the window again.  It might not feel as hot in the room, because the hot air isn't getting on your person directly and the wood is acting like a barrier, but it makes your A/C work harder than if you'd prevented the heat from coming in your house, at all.

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My brother custom built a green home out of straw, with mud walls.  The entire thing was designed to be energy efficient from top to bottom.  He shared a lot of the stuff with this site as he built it.  It was his huge project for a few years and we used to talk about the different thing he'd learn during the process.  And lots of the stuff was about misconceptions about efficiency or about stupid ways that we do things just because it's how we've always done it (like putting our air cooling ducts up in the hot ceiling).   That's where I learned this little factoid.