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It is 54 degrees outside. Inside my home it is 80 degrees. At night, as the outdoors gets cooler, the inside of my home continues to get warmer, at least with the windows closed. It's a relatively safe neighborhood, but not safe enough to leave a downstairs window open. Opening upstairs windows alone hardly makes a dent in the temperature.

Most of the heat comes from thermal mass I presume, meaning the walls and floors and ceilings store the heat from the day and release it all night, much to my sleeping displeasure. I can't sleep at temperatures above 75 degrees. We have some electronics plugged in, but not too much in that department.

As I walk the dog at 5:30 am, many of the neighbors have their windows closed and the air conditioning running. I reiterate that it is 54 degrees outside.

All of the homes in this development were built about five years ago. I'm sure they meet or exceed all the codes for energy use. And yet many of us are running our air conditioning when it is 54 degrees outside.

All we need to solve this problem is a downstairs window that has both a screen (for bugs) and jail bars (for intruders). The trick is to make the jail bars not look like jail bars, so there is some chance the homeowners association would allow them. The jail bars need not be grey vertical bars. They could be a design that adds a cool and funky look to your portal. For example, the barrier against intruders could be a peace sign, or a happy face, or a pine tree, whatever. And it could be whatever color works with your house.

Obviously this sort of solution is only useful in places and seasons where it is hot during the day and cool at night. But that is a lot of places.

Ideally that window, and a few upstairs, would be motorized and on a remote, so you can close them without getting out of bed if it gets too cold inside.

But my real question is this: If it is colder outside than inside, is there any reason you shouldn't run the air conditioning with your upstairs windows open?
 
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Sep 13, 2008
We have the same problem in a 1 story home isolated enough that you can leave both doors and every window in the house open. I am convinced that it is the attic. I think phasers comment may be one of the best I have seen on this forum. May just try that attic fan. Don't think the open windows will work. At least they don't here.

Oddly, our house is also colder than outside in the wintertime. I keep telling my beloved that this has to violate some law of thermodynamics and she keeps calling me a geek.

 
 
Sep 13, 2008
Our previous house got increasingly hot inside as the evening progressed even though it was cooler outside. The inexpensive solution was a "whole house fan" which we mounted on the ceiling in a central area of the house. It works by blowing hot air from the house into the attic and outside through attic vents. This air is displaced by cooler air coming through open windows. It really worked well! I notice there is an entry on whole house fans on Wikipedia.
 
 
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Sep 13, 2008
Scott, why not add an evaporative cooler, or a whole house fan?
One of these would pull cool air in from the outside, and push warm air out of the house.

You need to leave a window open somewhere - but it could be a second story window.
Alternatively, you could vent the incoming air to the attic - look for a product called updux.

Sounds like you also need an attic ventilation fan (it could even be solar powered).

Matt
 
 
Sep 13, 2008
Hey Scott: Whats wrong with leaving the windows open and running the air conditioning with the upstairs windows open? Well you are trading dollars for speed to be comfortable sooner. Much like driving around your car that overheated in the sun with the windows down and the air conditioner on.

Your idea that your hose heats in the late afternoon when the outside is cooling is partially correct, but you are continuing to heat-up your thermal mass by leaving it in the sun. Consider adding shade from trees or awnings.
Plus you have a big bubble of warm air in the attic that is and radiating down into your house.

The idea about the attic fan is really about a good one, you can get a fan with a thermostat at Home Depot. Better still, get an attic fan that is solar operated - a bit over a foot in diameter and sits on you roof = http://www.solatube.com/homeowner/solarstar.php

robert the architect
 
 
Sep 13, 2008
Gee Scott,

When I grew up in (in the fifties, in Sullivan Cty, NY) my dad had a simple and effective solution to shedding the heat-of-the-day from the house. When the temperature outside dropped below the inside temperature, he'd turn on the attic fan.

Of course, you could always survey a bunch of economists to perhaps come up with a better solution.
 
 
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Sep 13, 2008
If the homeowners association can prevent you from adding window bars, then you don't truly "own" your home, do you? Bet you couldn't paint your house pink, either. Tsk, tsk.
 
 
-1 Rank Up Rank Down
Sep 13, 2008
Get an apartment!
 
 
Sep 13, 2008
The compressor part of an AC will go off when the temperature drops low (at least for most of them) . I’m not sure what the temperature is, but it is higher than 54°F. Your AC is probably operating as a fan at temperatures higher than 60°.
 
 
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Sep 13, 2008
Unfortunately, you, like many other people, probably live in a home where the developer/builder went cheap, meaning that while your house meets code, it does not really have enough ventilation. This is very common.

Here is one easily accomplished solution: Install a large, powered, thermostat controlled ventilator in your attic. Normally, during the day, the ventilator cycles air through your attic to help pull heat out of your house (I'll bet it's 140F in your attic on a sunny day). For night time operation, install some simple louvers in the ceiling of each upstairs room, then open your upstairs windows. The ventilator then pulls the warmest air out of your house (ceiling and attic) and the make-up air is the nice fresh 54F air you are so craving. The thermostat will shut the ventilator off if it gets too cold. It is far more efficient than running the AC. The AC will work fine, but you are still putting the refrigerant through the Carnot cycle when all you really need is a fan. However, come to think of it, most AC units do have a fan/ventilation only mode, so they can just suck in that nice cool air. The problem with having the AC on your ground floor is that while it puts cool air where you want it during the day, at night it fills a big pool of cold air in your downstairs that still leaves you sweltering upstairs.

Bars are fine, though you have talked about them before, and besides, as others have noted, there are lots of better solutions...
 
 
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Sep 12, 2008
Good Idea, but you've said the exact same thing before (down to the point about large bars for bulgars, small bars for bugs).
 
 
-1 Rank Up Rank Down
Sep 12, 2008
Well, Scott, I guess you haven't been to Mayapur. The buildings built by the Hare Krishna's near navadwip were designed by our Polish members, and what sweet cubes of cement they are. In Summer, our walls feel like the next room is on fire. In winter, it feels like a Russian Prison Cell. And when it floods here, we have furry walls of mould.

And re: Air-conditioning - with power cuts every half hour, need I say more?
 
 
Sep 12, 2008
One way to cool your upstairs would be to open the windows - ideally on opposite sides of the house to get cross ventilation as wind on one side of the house pushes air through the house to the other side - and to run a ceiling fan, which will move the air and draw cold outside air in. You can avoid most air conditioning this way, without relying on the chimney effect of the downstairs window that you're focusing on.
 
 
Sep 12, 2008
I live in Canada: Alberta to be exact. My home is just outside of a small town in the foothills of the Rocky Mountains.
I have no bars on my windows, so we keep our house cooled by opening a few windows This time of year we are getting frost some nights. Just thought I'd throw in a different perspective.
 
 
Sep 12, 2008
I think that the answer to Scott's question is complex enough - it depends on exactly how the air currents in his house flow - that he would have to test it empirically, by comparing energy use and temperature change on days with the windows open vs. closed (with AC running).

Why, when Scott asked a direct question, did no one try to answer his question?
 
 
Sep 12, 2008
hey Scott I'm just wundering what ever happened to the dilbert TV show? I think Dilbert Go a lot further if you made more episodes.
 
 
Sep 12, 2008
In Australia it is common place to have security screens to keep the bugs away, and yet strong enough to prevent any burglary attempts. They are easy enough to open when needed, and can be fitted to both doors and windows. No need to get jail bars, you just need to make your idea a little different (ie: make your screen as strong as jail bars). The old kill two birds with one stone adage.
 
 
Sep 12, 2008
Wouldn't some sort of vent, instead of a window be a better idea. Something that is too small for even animals to fit through but could allow the air to exchange freely. Maybe a collection of them; some near the ground level and some up high (second floor, or whatever is highest)
 
 
Sep 12, 2008
You get plenty of afternoon breeze where you live. Close the blinds on W and SW facing windows in the afternoon, open upstairs windows in the evening. Helps to have good shade on the S side. We do this in San Ramon and the upstairs bedrooms are quite comfortable by about 9PM. Run the AC if this doesn't cool the house down fast enough. You fancy schmantzy Blackhawk people can probably afford someone who can install something that will control your blinds and windows on a wifi bluetooth tablet controlled timer gizmo. Or you could get window and attic fans like everybody else is telling you.
 
 
Sep 12, 2008
Wrought iron security designs meet any posh housing standards:
Example:
http://www.falconironart.com/product4_security.html
 
 
Sep 12, 2008
Wow - I cannot imagine living somewhere where you can't open your windows unless they have bars on them. Scary!
 
 
 
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