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Hello can somebody help me out.
I’m in the process of build a 2,800 sq.ft.2 story home with radiant floor heat on the first floor. The floors will be stamp concrete on the first story. In the living room their is a 13 foot vaulted ceiling that opens up to the second floor loft. The living room also contains a high efficiency gas fire place with a fan and thermostat.
Now my question! I planed a heat exchange unite to be installed as well. I thought that this would help heat the upper floor as well as keep down interior moisture which is a problem in our area. (pacific north west 100 yards from a river),My builder is sugesting that this is a wasted expense. I don’t want to spend money that is not nessasary! Will I need another heat source for the upstairs or will hot air raising and a couple of fans be enuogh? We are on a tight budget but would rather pay now than later.
Thank you for all your input.
Drew
Replies
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Sounds very much like the layout of my hoiuse, butin a much milder climate. My upstairs loft bedroom stays plenty warm enough off the downstairsa radiant. I strongly suggest you create a separate zone for the living room because it needs to be on more of the time. Put downstairs closed off rooms on a at least one) separate zone. Do you have any upstairs room other than the loft? They could be boosted by a separate zone for PEX tubing between the joists with 1) aluminium plates if you're going to run one temperature throughout or 2) w/o plates if you can run hotter water to through the tubing in the joists.
A heat recovery ventilator will lower the humidity, especially in a tight house. If you have allergies to mold or hate bath towels mildewing on the rack, that might be reason enough to spend the money. But you won't recover it in utility bills, lacking my -20F winters.
As to heating the upper floor with the HRV, the only way I see to do a bit of that is to draw the stale air from upstairs, causing more flow towards upstairs. But usually you want to draw stale air from the bathroom, kitchen, and bedrooms where it is generated. Definitely put the incoming cool air in at an unobtrusive spot on the radiant floor where it will quickly warm. And plan a separate outlet for the range hood and clothes dryer exhaust. -David
*I've got a similar situation in two apartments that I'm building. They are located on the second and third floors of the building. The second floor is lightweight concrete and PEX tubing for the radiant, but I haven't figured out how to heat the 3rd floor bedrooms. I'm going to use power vent DHW heaters for the boilers. I've thought about elec baseboard and fan-coils so far. The 3rd floor will be timber frame with 4 foot joist spacing so I didn't think PEX would look too cool. It just occurred to me that copper could look pretty neat in these Chicago loft style apartments and I figured it wouldn't be that expensive and very good heat transfer. Any Comments?
*Jeff: Copper has far better heat transfer than cross-linked polethylene (PEX) but it doesn't make much difference. The resistence to heat flow is almost all in the air film on the outside of the tubing. But I agree that copper could look good in some settings. Run hot water (like 120F or more instead of 80-85F in the floor) and you'll get reasonable heat off of it. -David
*Assuming that the ceiling is still open under the upstairs area at your current stage of construction, it would seem to be fairly economical to add some loops of tubing attached to the underside of the upper floor with some insulation between the tubing and the ceiling below it (with, I believe, a recommended 3" of airspace between the tubing and the insulation.) Since you are already using hydronic heat, you would only be out the cost of the tubing, valves, probably a small pump, and a distribution manifold. This way if you choose to let the temperature drop in the lower part of the house, you could still keep the desired temperature in the upper floors. For me, the few hundred dollars would be worth it for the extra heating flexibility. There is an article on using hydronic heat in an "off the grid" house in this month's issue of Home Power magazine. They describe using multiple low power DC pumps (10 watts or less) with PEX tubing in concrete floors or under wood floors. The heat source is solar and gas or oil fired boiler. Seems to have some good general and specific information. To view in Adobe Acrobat, go to http://www.homepower.com/ page down and click on "Download the full issue", and then on "Current issue download", and then on "Pages 32 - 45".If it works, this link may save you a couple of clicks: http://www.homepower.com/download.htm#CurrentIssue
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Hello can somebody help me out.
I'm in the process of build a 2,800 sq.ft.2 story home with radiant floor heat on the first floor. The floors will be stamp concrete on the first story. In the living room their is a 13 foot vaulted ceiling that opens up to the second floor loft. The living room also contains a high efficiency gas fire place with a fan and thermostat.
Now my question! I planed a heat exchange unite to be installed as well. I thought that this would help heat the upper floor as well as keep down interior moisture which is a problem in our area. (pacific north west 100 yards from a river),My builder is sugesting that this is a wasted expense. I don't want to spend money that is not nessasary! Will I need another heat source for the upstairs or will hot air raising and a couple of fans be enuogh? We are on a tight budget but would rather pay now than later.
Thank you for all your input.
Drew