Using attic heat for the house - Page 7

Patrick · 10-31-10, 12:56 PM

Quote:

Originally Posted by Daox

Alright, here is a rough picture of what I was thinking of. I am very much open to suggestions. I'd really love to simplify it, but I'm not sure how without sacrificing functionality and ease of building. Also, the flapper vents would seal better if they were oriented vertically (90 degrees rotated from how they are in my picture), but the air can only flow upwards then (so gravity holds it closed).

I like your design, except that I would probably put the filter in the top or end of the box to make it easier to change.

Daox · 10-31-10, 03:53 PM

Good point. I avoided putting it on the top due to dust settling on it. Perhaps on the side would be a good compromise. I was thinking of attaching it with some sort of channel so you could just slide it in and out.

Phantom · 11-03-10, 11:47 AM

Instead of having the filter under or on top cut the side at an angle and add a lip to hold it in place. So instead of the left hand side being an L with the filter at the bottom make it \ with the \ being a filter.

GaryGary · 11-03-10, 08:53 PM

Hi,
This one requires a "small" modification to your attic roof, but it appears to work well:

IWillTry.org Build a Solar Attic

-----------
I wonder how well the attic would do as a heater if one eliminated the attic ventilation and did some form of simple insulation on the north facing part of the roof.

I realize the attic ventilation is there for a reason, but if one could get worthwhile heat from the attic, maybe it would be worthwhile having forced attic ventilation controlled by sensors that only ventilate when the attic needs ventilation (maybe when the humidity is too high?).

Seems like there ought to be some simple way to turn an attic into an effective solar collector?

Gary

Daox · 11-03-10, 10:30 PM

Very good points Gary. I agree the attic is kind of a perfect but less efficient solar collector. You might as well use it for something. My first idea was just to run some pex tubing up there to act as a hot water preheater. You'd have to drain it during winter of course. But, that would be a very inexpensive option. This blower idea came a bit later, but I think it will translate into more energy captured vs the water preheating.

I really like the idea of closing off the attic vents to capture more heat. It would be quite interesting to see the effects this would make on how hot the attic gets.

NeilBlanchard · 11-08-10, 10:20 AM

Wouldn't make sense to put a heat pump in the attic? This would "recirculate" at least some of the heat back into the house.

The vents are needed to let moisture out. If you have a nearly perfect vapor barrier in the ceiling, then you could close them off.

danneva · 11-23-10, 08:47 AM

this thread is too informative. It gave me some ideas. thank you all.

iamgeo · 11-23-10, 09:26 AM

I'm thinking that you should be drawing air from near the top of the attic. As I see it, as the air is drawn from near the attic floor cooler air will be drawn into the attic via the soffets. Then the fans will be pushing that cooler air into your house.

AC_Hacker · 11-24-10, 01:02 PM

Quote:

Originally Posted by NeilBlanchard

Wouldn't make sense to put a heat pump in the attic? This would "recirculate" at least some of the heat back into the house.

Good idea. I've learned that this is being practiced in some parts of the South.

If you're going to do this, it's important to vent the output from the "outside" unit of your heatpump out of the attic, otherwise your attic will become much colder than ambient in the winter and much hotter than ambient in the summer.

These conditions wiould be undesirable.

-AC_Hacker

AC_Hacker · 11-24-10, 02:34 PM

delete... double post

10-31-10, 03:53 PM	#62
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Good point. I avoided putting it on the top due to dust settling on it. Perhaps on the side would be a good compromise. I was thinking of attaching it with some sort of channel so you could just slide it in and out. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

11-03-10, 10:30 PM	#65
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Very good points Gary. I agree the attic is kind of a perfect but less efficient solar collector. You might as well use it for something. My first idea was just to run some pex tubing up there to act as a hot water preheater. You'd have to drain it during winter of course. But, that would be a very inexpensive option. This blower idea came a bit later, but I think it will translate into more energy captured vs the water preheating. I really like the idea of closing off the attic vents to capture more heat. It would be quite interesting to see the effects this would make on how hot the attic gets. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

11-24-10, 02:34 PM	#70
AC_Hacker Supreme EcoRenovator Join Date: Mar 2009 Location: Portland, OR Posts: 4,004 Thanks: 303 Thanked 723 Times in 534 Posts	delete... double post Last edited by AC_Hacker; 11-24-10 at 02:36 PM.. Reason: delete... double post

11-03-10, 11:47 AM	#63
Phantom Apprentice EcoRenovator Join Date: Sep 2010 Location: Louisville, KY Posts: 101 Thanks: 13 Thanked 8 Times in 7 Posts	Instead of having the filter under or on top cut the side at an angle and add a lip to hold it in place. So instead of the left hand side being an L with the filter at the bottom make it \ with the \ being a filter.

11-03-10, 08:53 PM	#64
GaryGary Apprentice EcoRenovator Join Date: Nov 2008 Location: SW Montana Posts: 139 Thanks: 1 Thanked 21 Times in 15 Posts	Hi, This one requires a "small" modification to your attic roof, but it appears to work well: IWillTry.org Build a Solar Attic ----------- I wonder how well the attic would do as a heater if one eliminated the attic ventilation and did some form of simple insulation on the north facing part of the roof. I realize the attic ventilation is there for a reason, but if one could get worthwhile heat from the attic, maybe it would be worthwhile having forced attic ventilation controlled by sensors that only ventilate when the attic needs ventilation (maybe when the humidity is too high?). Seems like there ought to be some simple way to turn an attic into an effective solar collector? Gary

11-08-10, 10:20 AM	#66
NeilBlanchard Journeyman EcoRenovator Join Date: Dec 2009 Location: Maynard, MA Eaarth Posts: 383 Thanks: 78 Thanked 39 Times in 32 Posts	Wouldn't make sense to put a heat pump in the attic? This would "recirculate" at least some of the heat back into the house. The vents are needed to let moisture out. If you have a nearly perfect vapor barrier in the ceiling, then you could close them off.

11-23-10, 08:47 AM	#67
danneva Lurking Renovator Join Date: Nov 2010 Location: USA Posts: 5 Thanks: 0 Thanked 0 Times in 0 Posts	this thread is too informative. It gave me some ideas. thank you all.

11-23-10, 09:26 AM	#68
iamgeo Apprentice EcoRenovator Join Date: Aug 2010 Location: Lakehills, Tx Posts: 168 Thanks: 4 Thanked 10 Times in 9 Posts	I'm thinking that you should be drawing air from near the top of the attic. As I see it, as the air is drawn from near the attic floor cooler air will be drawn into the attic via the soffets. Then the fans will be pushing that cooler air into your house.