Project ideas for cooling my house.
Dgswaner
Posts: 795
I live in a 3 story (2 + basement) home which faces West, and I live in Utah, during the summer/fall I get a good dose of sun which causes my house to heat up quite a bit. The main level stairs are open to the upper level, which causes the upper level to get unbearably hot in the late evening. which translates to us cranking the AC costing us as much at $200 a month in the summer. The heat also comes down from the attic as well as, even though it is properly insulated. My attic gets hot enough to melt plastic (my router /cry). I have a few ideas that I want to implement to reduce heat, but I'd be curious to hear your suggestions. Mostly I would like to find a way of using the heat (energy) in the attic to help with the solution. This is a serious problem that I need to address, you input would greatly appreciated.
in process or definite plans:
Plant shade trees, will be beneficial in future years, doesn't help with the attic.
Moving our Family Room to the basement, (already done) helps not hanging out up stairs, our basement is as much as 20 deg. cooler in the late afternoon.
To address the attic heat I want to install fans (preferably solar) to blow the hot air out of the attic.
I've considered making the floor registers automatic so the AC only goes to critical areas or occupied areas, we do this manually to some extent already.
Thanks for your input, FYI out of the box ideas are welcome!
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
DGSwaner
"When in doubt, use C4" - Jamie Hyneman, Myth Buster
in process or definite plans:
Plant shade trees, will be beneficial in future years, doesn't help with the attic.
Moving our Family Room to the basement, (already done) helps not hanging out up stairs, our basement is as much as 20 deg. cooler in the late afternoon.
To address the attic heat I want to install fans (preferably solar) to blow the hot air out of the attic.
I've considered making the floor registers automatic so the AC only goes to critical areas or occupied areas, we do this manually to some extent already.
Thanks for your input, FYI out of the box ideas are welcome!
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
DGSwaner
"When in doubt, use C4" - Jamie Hyneman, Myth Buster
Comments
Solar is great but I think you need something that will move high volumes of air out of your attic. We have a large (and loud) attic fan that kicks on at 80 degrees, the attic still gets quite hot on sunny days. We could probably use a couple more of them.
I also think that adding insulation is a good investment.
A while back I saw these reflective films that you put up in your attic against the roof. The idea is that the heat is reflected back to the roof to keep the attic cooler. Don't know if they work. I wonder just how much hotter the roof would get.
Rich H
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
The Simple Servo Tester, a kit from Gadget Gangster.
Your West wall is basically a trombe wall without a vent. If you create a variation of a trombe wall where in the summer time the INPUT vent could come from the 'cool basement' or East end of the house, and the OUTPUT vent is allowed to escape into the attic, it should create a positive air flow into the attic to remove the heat. In the winter time the INPUT vent should come from the West end of the house, and the OUTPUT vent should also escape into the West end of the house. The trombe wall does not need to be thick at all... think double paned glass window... The trombe wall effect is created between the Brick of the house and the drywall, or a single pane window creating an interior upward airflow of heat that hugs the window. If insulation is present (between Brick and drywall) it worsens the effect because it dampens the airflow... in your case there is no airflow because essentially it's a sealed chamber or single pane window.
What color are the bricks? If there are bricks, that is where most of your heat is retained, and then later transferred into the house.
Can you post a picture of your West wall?
Remember this... you already have the Solar Power... it's just in the form of Heat. Put it to good use in your favor.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Beau Schwabe
IC Layout Engineer
Parallax, Inc.
if you have a well you can do this: http://lifehacker.com/290684/get-free-air-conditioning-with-a-diy-heat-exchanger
installing a large vent fan in the attic with a cheap thermostat to control it should help a lot also. Since the thermostat can not likely power the fan directly have it run a relay to control the circuit.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Lots of propeller based products in stock at affordable prices.
Following is a gizmo which makes small amounts of electricity from heat in the air. For now they are just using these to power electronic devices, but in the future?
http://www.energyharvestingjournal.com/articles/thermoelectric-ambient-energy-harvester-00001437.asp?sessionid=1
Here is the company web site and a bit on how this works...
http://www.perpetuapower.com/technology.htm
Post Edited (kf4ixm) : 4/21/2010 12:55:53 PM GMT
-dan
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Arguing with myself--sometimes me, myself, and I don't always agree.
(Former) Caterpillar product support technician
What you describe is basically what happens without adequate ventilation. In the winter it is a desired effect, but in the summer time such as that for Dgswaner, it builds up unwanted heat. If you can use the convection effect from that heat buildup and vent it into the attic, you create a positive air flow to the attic, killing two birds with one stone.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Beau Schwabe
IC Layout Engineer
Parallax, Inc.
heat goes up, cold·falls down...·
just my 3 cents
john
The properly vented trombe wall isn't an option, my walls are vinyl sided, 2x6 walls with batt insulation. All interior walls are finished or I would do some testing.
My new plan, when it's hot enough is to put a couple of vents in the attic on a thermostat, to keep air moving out of the attic, and hopefully keep it several degrees cooler. In the late afternoon, when we are home, I want to see if it will draw up the cool air from the basement with just the attic fan(s). If not I want to add a large fan into the attic access (in the 2nd floor ceiling). and see if I can get some good air flow from the basement that way.
thanks for the input, as soon as it gets hot enough I'll return and report!.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
DGSwaner
"When in doubt, use C4" - Jamie Hyneman, Myth Buster
I had one installed on my house when we replaced the roof.... It seems to have made a marked improvement.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
"puff"...... Smile, there went another one.
They do not come on at a lower temperature. I wanted the fan to come whenever the
Attic temperature was above 78 degrees and seven degrees warmer than the outside temperature. This delayed the eventual attic heatup.
On very hot days the fan would come on at 90 degrees, as the outside temperature climbed above 90. The fan remained on. I occasionally had a situation, usually late
On a hot afternoon where the fan was actually pumping HOTTER air into the attic.
I solved these problems by removing the fan thermostat and installing an lm34 sensor
To monitor the attic temperature, and an lm34 to monitor the outside temperature.
I used a stamp 2 to monitor the temperatures and turn the fan on or off, when the
attic temperature is above 78 degrees and 7 degrees warmer than the outside
Temperature. I used a solid state relay (thyristor) to handle the AC on/off function.
I have this installed and working, but as with most projects, it is a work in progress.
This spring I hope to install a fan or blower to pump outside air into the attic from
The opposite side of the roof.
Larry