Home and Auto Any HVAC contractors out there?

**The Bad Guy** · 06-20-2011, 05:26 PM

I'm in the final stages of signing a contract for my house. The builder wants to put the registers/returns near the floor for my central air and forced hot air. To me, that seems absurd because the cold air is never going to rise in the summer and the house will still be hot.

I suggested that they put the hot air ducts in the same spot, but move the cold air ducts in the ceiling.

Is this a real feasible thing to ask? Is it real difficult to pull off? I figured they should be coming from the same duct, but since we are putting the central air, furnace and tankless hot water heater in the basement in a utility room, we didn't know how difficult this would be to do.

I'm meeting with a different HVAC guy tomorrow and didn't want to ask something like this if it was real unreasonable.

Thanks in advance for any help.

**Rain Man** · 06-20-2011, 05:34 PM

You would have separate ducts for heating and cooling? I've never heard of that. Usually the same duct system works for both.

kstater · 06-20-2011, 05:39 PM

The registers are in the floor in my house(no basement) have no issues with the house being cool.

**The Bad Guy** · 06-20-2011, 05:42 PM

Quote:

Originally Posted by kstater

The registers are in the floor in my house(no basement) have no issues with the house being cool.

I will have a basement, but right now it will only be used for storage, so this is where my concern lies.

**Rain Man** · 06-20-2011, 05:46 PM

I think that you want both cool air and hot air on the floor rather than the ceiling, so if you put the ducts low, the cool air will stay there and the hot air will at least pass through. If you put the ducts high, the cool air will eventually reach you down low but the hot air won't. So lower is better.

As you said, having cool air high and hot air low is even better, but I think that would double your ductwork cost and might cause some other problems as they try to fit them all through the walls.

Brock · 06-20-2011, 05:49 PM

If you have a basement, I'd run everything under the floor. Easy access, if nothing else, plus I'll bet what you're thinking of doing would double your installation costs.

**Rain Man** · 06-20-2011, 06:00 PM

As an aside, my biggest regret when we redid our kitchen was not putting in a radiant heating system under the tiles. It wasn't that expensive and would make the kitchen much more comfortable in the winter walking on warm tiles rather than icy cold ones.

kstater · 06-20-2011, 06:03 PM

Quote:

Originally Posted by Rain Man

As an aside, my biggest regret when we redid our kitchen was not putting in a radiant heating system under the tiles. It wasn't that expensive and would make the kitchen much more comfortable in the winter walking on warm tiles rather than icy cold ones.

You can do that aftermarket. Get some copper wire. Wrap one end around the coil on your stove. Then create your pattern on the floor. Just have to remember to turn the oven on before you go to bed so the floor will be warm in the morning.

**Rain Man** · 06-20-2011, 06:05 PM

Quote:

Originally Posted by kstater

You can do that aftermarket. Get some copper wire. Wrap one end around the coil on your stove. Then create your pattern on the floor. Just have to remember to turn the oven on before you go to bed so the floor will be warm in the morning.

That's a good idea. And I bet my cat will learn quickly to step around the copper.

Mr. Laz · 06-20-2011, 06:15 PM

i've always wonders about the metal,leaky air ducts. They have to leave gaps for temperature expansion and stuff but i would think that there should be a plastic or coating available now that would make those expansion gaps unnecessary and make the ducting much more efficient.

Chieftain58 · 06-20-2011, 06:16 PM

They come out of the same register... In AZ where I lived for 5 years everything was in the ceiling and in the midwest everything is in the floor. You would probably need 2 different units if you were to do this or maybe you could divert the air someway...anyway I bet it would cost a bundle.. Make sure your having the exterior walls framed by 2x6 or bigger with plenty of insulation and use good windows.

**The Bad Guy** · 06-20-2011, 06:19 PM

Quote:

Originally Posted by Brock

If you have a basement, I'd run everything under the floor. Easy access, if nothing else, plus I'll bet what you're thinking of doing would double your installation costs.

Truth. I'm going to talk to the HVAC guy tomorrow to see my options. I just didn't understand how cool the house would get with a lower register and having a basement to sink all the cold air.

**mikeyis4dcats.** · 06-20-2011, 07:23 PM

The same duct is used to supply cooled and heated air. The term "cold air return" just means that that is the return duct which carries air back to the unit.

If your ductwork runs through the attic, it gains more heat or cold from the untreated attic space than if run in the basement or in a crawlspace. For a house on a slab, this is usually the only choice though. Given the choice, you'd be better to run it under the floor.

bobbymitch · 06-20-2011, 07:41 PM

As to the air outlets, why not just add an extra outlet? i.e. have two in the same room supply cavity. For summer cooling, ya close the one near the floor and open the one close to the ceiling. In winter, ya close the one near the ceiling and open the one close to the floor.

For return air ducts, I mainly see the registers about 6 feet off the floor.

**The Bad Guy** · 06-20-2011, 08:14 PM

Quote:

Originally Posted by bobbymitch

As to the air outlets, why not just add an extra outlet? i.e. have two in the same room supply cavity. For summer cooling, ya close the one near the floor and open the one close to the ceiling. In winter, ya close the one near the ceiling and open the one close to the floor.

For return air ducts, I mainly see the registers about 6 feet off the floor.

I guess that's what I'd be trying to accomplish.

Wouldn't there still need to be different duct work though?

06-20-2011, 05:26 PM
The Bad Guy Scott Pioli Join Date: Jan 2001 Location: The Copacobana Casino cash: $9373645	Any HVAC contractors out there? I'm in the final stages of signing a contract for my house. The builder wants to put the registers/returns near the floor for my central air and forced hot air. To me, that seems absurd because the cold air is never going to rise in the summer and the house will still be hot. I suggested that they put the hot air ducts in the same spot, but move the cold air ducts in the ceiling. Is this a real feasible thing to ask? Is it real difficult to pull off? I figured they should be coming from the same duct, but since we are putting the central air, furnace and tankless hot water heater in the basement in a utility room, we didn't know how difficult this would be to do. I'm meeting with a different HVAC guy tomorrow and didn't want to ask something like this if it was real unreasonable. Thanks in advance for any help.
Posts: 23,212

06-20-2011, 05:34 PM	#2
Rain Man NFL's #1 Ermines Fan Join Date: Jul 2001 Location: My house Casino cash: $3358491 VARSITY	You would have separate ducts for heating and cooling? I've never heard of that. Usually the same duct system works for both. __________________ I'm putting random letters here as a celebration of free speech: xigrakgrah misorojeq rkemeseit.
Posts: 141,248

06-20-2011, 05:39 PM	#3
kstater Custom User Title Join Date: Jan 2007 Casino cash: $1916563	The registers are in the floor in my house(no basement) have no issues with the house being cool.
Posts: 39,159

06-20-2011, 05:46 PM	#5
Rain Man NFL's #1 Ermines Fan Join Date: Jul 2001 Location: My house Casino cash: $3358491 VARSITY	I think that you want both cool air and hot air on the floor rather than the ceiling, so if you put the ducts low, the cool air will stay there and the hot air will at least pass through. If you put the ducts high, the cool air will eventually reach you down low but the hot air won't. So lower is better. As you said, having cool air high and hot air low is even better, but I think that would double your ductwork cost and might cause some other problems as they try to fit them all through the walls. __________________ I'm putting random letters here as a celebration of free speech: xigrakgrah misorojeq rkemeseit.
Posts: 141,248

06-20-2011, 05:49 PM	#6
Brock Say hello to my little friend Join Date: Aug 2000 Location: Larryville Casino cash: $9598422	If you have a basement, I'd run everything under the floor. Easy access, if nothing else, plus I'll bet what you're thinking of doing would double your installation costs.
Posts: 47,314

06-20-2011, 06:00 PM	#7
Rain Man NFL's #1 Ermines Fan Join Date: Jul 2001 Location: My house Casino cash: $3358491 VARSITY	As an aside, my biggest regret when we redid our kitchen was not putting in a radiant heating system under the tiles. It wasn't that expensive and would make the kitchen much more comfortable in the winter walking on warm tiles rather than icy cold ones. __________________ I'm putting random letters here as a celebration of free speech: xigrakgrah misorojeq rkemeseit.
Posts: 141,248

06-20-2011, 06:15 PM	#10
Mr. Laz Don't Tease Me Join Date: Dec 2000 Location: KS Casino cash: $11047037	i've always wonders about the metal,leaky air ducts. They have to leave gaps for temperature expansion and stuff but i would think that there should be a plastic or coating available now that would make those expansion gaps unnecessary and make the ducting much more efficient. __________________ Last edited by Mr. Laz; 06-20-2011 at 08:47 PM..
Posts: 95,626

06-20-2011, 06:16 PM	#11
Chieftain58 Fan club member Join Date: Jun 2002 Location: Land of OZ Casino cash: $10005117	They come out of the same register... In AZ where I lived for 5 years everything was in the ceiling and in the midwest everything is in the floor. You would probably need 2 different units if you were to do this or maybe you could divert the air someway...anyway I bet it would cost a bundle.. Make sure your having the exterior walls framed by 2x6 or bigger with plenty of insulation and use good windows. __________________
Posts: 1,626

06-20-2011, 07:23 PM	#13
mikeyis4dcats. Scarlett Johansson's boytoy Join Date: Nov 2006 Casino cash: $9555998	The same duct is used to supply cooled and heated air. The term "cold air return" just means that that is the return duct which carries air back to the unit. If your ductwork runs through the attic, it gains more heat or cold from the untreated attic space than if run in the basement or in a crawlspace. For a house on a slab, this is usually the only choice though. Given the choice, you'd be better to run it under the floor. __________________
Posts: 12,526

06-20-2011, 07:41 PM	#14
bobbymitch Starter Join Date: Feb 2002 Location: Midwest coast Casino cash: $9893512	As to the air outlets, why not just add an extra outlet? i.e. have two in the same room supply cavity. For summer cooling, ya close the one near the floor and open the one close to the ceiling. In winter, ya close the one near the ceiling and open the one close to the floor. For return air ducts, I mainly see the registers about 6 feet off the floor. __________________ This is the place where brilliant minds assemble to willfully pool ignorance with questionable logic in order to reach absurd conclusions.
Posts: 655