My husband and I live in Montana and are getting ready to build a 32×36 garage/shop (I say garage, but no car will ever see the interior while we live there!)with a studio apartment over it. We are trying to decide how to heat it efficiently and inexpensively. He wants radiant floor heating in the slab, and believes that this will rise and heat the upstairs apartment too with maybe some supplemental heating if necessary (like wood or propane stove or propane heaters). He is a carpenter and does some work at home sometimes, but I worry that we will end up heating a huge area that is not used regularly. Also if we need to leave openings for heat to rise, then I figure that the dust will rise with it. Does anyone have any comments or suggestions about heating this type of space? What about cooling (without A/C) the upstairs space in the summer?
Thanks!
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I have a 2,900 sf radiant heated slab for my garage / basement. The actual surface temps are not that high. I don't think I would get enough heat rising thru the floors to keep the floor above very comfortable. Once the slab warms up that heating zone is not not activated that much. I don't think you would save that much in material costs by not heating the upper level.
Radiant is known for it's reduced stratification (rising hot air), not for being very good at it.
I love radiant, but if this is only to be periodically heated, then wall mounted gas air heaters are probably the cheapest and best bet. I would pipe the slab though, so if it is to be used more often down the road it can be plumbed for radiant.
If the studio apartment is to be used full time, that small of an area could be done with radiant fairly inexpensively. You'd have to be sure to insulate below though if the shop is not heated full time.
-=Northeast Radiant Technology=-
Radiant Design, Consultation, Parts Supply
http://www.NRTradiant.com
Hi Montana,
I'm in Bozeman.
I have an attached shop/garage and a detached shop/barn/garage. I heat both with solar. These are the descriptions/plans for the two shop/garage heaters:
This is the barn/garage solar thermosyphon heater -- cost me $350 to build, and saves more than that in propane costs each year at our current $2 per gallon propane:
http://www.builditsolar.com/Projects/SpaceHeating/solar_barn_project.htm
This is the attached garage heater:
http://www.builditsolar.com/Projects/SpaceHeating/garcol.htm
I like both of them, and they heat quite well on sunny or partly cloudy days. On cloudy days, some form of back up heat is needed.
I particulary like working in the 2nd one, in that it provides outstanding natural lighting.
With more attention to insulation and infiltration and the addition of more thermal mass, either of these heaters could carry over a cloudy day with little or no backup heat.
More solar shop heaters here:
http://www.builditsolar.com/Projects/SpaceHeating/Space_Heating.htm
Gary
http://www.BuildItSolar.com
Gary,
goodl inks, thanks for posting them
Thanks Gary. We will have a nice south facing wall that the first project might work great for. I am excited to print out your article and show it to my husband. I think he will love it. My mother lives in the Upper Peninsula of Michigan totally off of the grid with only solar and wind power for all of her needs, my husband has done lots of work on her place, and always leaves more interested in the subject than the last time.Great site especially with the way propane and energy prices are going!
Thanks- Aimee
(ps- we are in Potomac, MT east of Missoula.)
I would do 2 systems. That is the only way to keep the dust out of the space above.
Shop area would get a tubular infrared radiant heater. They make them for low ceiling areas. Because it warms objects, it is cheaper to run than a gas fired unit heater. I would consider a PTAC unit to provide cooling.
If you will be on the floor, then in floor radiant would be nice. Due to the thermal mass of the concrete, it takes a long time to adjust temps up or down.
Apartment would get a small furnace and A/C. A/C is not too expensive to run. No real easy way to provide "cooling" without A/C unless you design smart like cross ventilation and generous overhangs to provide shade.
Most importantly, the exterior walls would be 2 x 6 or even 2 x 8 and blown in cellulose insulation. The added lumber cost will pay back quick with lower heating bills.