Simi free heat just over our heads?????

[Birdmmjb]

I may be off my rocker but here in southern AR even in the winter the attic gets hot I mean really hot. we have turbins on the roof to let this heat escape but can we make use of it instead of venting it?

Why not vent some of that excess heat into the living area by way of somthing like a dryer vent near the roof and a small fan to pull the warm air down into the house. Compleate with a draft flap or shutters to prevent unwanted heat gain in the summer of heat loss during the night during winter months.

A thermometer placed in or near the vent would show the home owner when the attic temp was high enough to do some good and the fan could be turned on and off manually or a thermostat could be rigged.

You would probibly wnat to screen off the opening to prevent critters 4 and 8 legged from using it as a highway into the house when the vent shutters were opened for the air to circulate.

I see somthing the size of a bathroom fan set to run in reverse.

What do you think?

Jan

[snowcrow]

Hi Jan, sounds like a great idea, but you might want to do so through some kind of heat exchanger. That insulation dust is not something you want in your living space!! You will want to put the intake and outlet vents near the floor where all the cold air is. You can use cheap black stovepipe for your ductwork and hide it in the closet where it goes up into and down from the attic. The vents could come out right though the closet wall. A bathroom fan would work great on the intake side, as is!!  This may sound like a lot of work but it could save you big on your heating bill!

Blessings, Snow Crow

[elt]

A couple of us are doing that...

http://www.fieldlines.com/story/2006/1/22/7044/09848

After using mine through its first winter I can say that if it's sunny and if its warmer than about 40F, then mine keeps my shop warm enough from about 10 am to sundown.

Below 40 degrees, the the attic may be warmer than outside but I need a higher temperature rise for the air to be warm enough to heat the work area. Even so, last winter was fairly mild and I estimate that the attic provided about 25% of my heating needs.

For the cost, I think it's a no-brainer... go for it!

I did notice that rain sucks the heat right off the roof so when the roof is wet, the vent heater is practically useless. I'm encouraged enough, though, that this year I will add a more traditional solar hot air heater to give me a greater temp raise for the colder days and a bit of heat when the roof is covered with snow.

Hope that helps,

- Ed.

[GaryGary]

Hi,

Here is another scheme to make use of attic heat -- a little more involved, but captures more heat:

http://www.builditsolar.com/Projects/SpaceHeating/BlackRoof/BlackRoofCol.htm

Can also be used for summer cooling.

Gary

[SteveCH]

I cannot come up with a downside, as long as, like someone else suggested, you are not sucking any component of any insulation into the living space. And, just pondering here, it might not be good if you were replacing this heated air with air from the living quarters that was really humid, as the moisture could condense up there. You'd have to consider this, might not be a factor in your case.