Grage Heating question for Northern Wyoming.
Hi all,
Would love to get everyone take on this project.
We are building a new home outside of Cody Wyoming (Climate zone 6 bordering 7) and are planning on starting with the garage/workshop. This will be a semi-conditioned space that will have a minimum amount of heat to keep things from freezing.
-There will be a two car garage with a single door and a 500 sqf woodshop
-part of the garage storage area will eventually be used for solar energy storage batteries.
-It will be built into a hillside in the style of a walk out basement partially due to the terrain and for wind mitigation.
-architect has R19 walls, R40 ceiling, with sheet-rock but would like to up these R values depending on material costs when we start construction.
Right now I am leaning towards an in-slab hydronic system for the steady state heating to keep it above freezing and then have on-demand heating when the spaces are in use. A wood-stove in the wood-shop and ceiling mounted infrared radiant in the garage.
I am pushing for in-floor since air-sealing is going to be a major challenge in both spaces (the dust extraction system in the wood-shop will be externally vented with makeup air) and feel like heating the slab would be the best way to deal with that.
Ideally I would like to use a heat pump for the in-floor heating with a propane backup for those extra cold days (-20 happens every winter and -50 is possible). Depending on cost I would like to have the shop zoned separately in case I need to up the temperature over-night for a project that is drying/setting up.
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Replies
I don’t see any problems with your proposed plan, do you have any specific questions about it?
I generally recommend against batteries, but if you plan to install them, I strongly recommend building a fire rated room to contain them. I would use a double layer of 5/8” type X drywall on all walls of that room and the ceiling, and I’d use a fire door too (although residential fire doors leave a lot to be desired in terms of their actual fire ratings). If those batteries ever have a catastrophic fault, you’ll have a major fire in that room. The fire rated construction buys you extra time to safely evacuate the building, and it’s not very expensive to build that way.
Bill
Thanks Bill, No real question more second guessing myself. Good call out on the battery fireproofing I will mention it to the architect. Its part of the reason I decided to condition the garage so we could move dangerous stuff like that out of the house.
You didn't mention under-slab insulation, nor thermal break between the slab and foundation /stem walls. Is that part of your plan?
Yes it’s part of my plan but I need to make sure it’s part of the architects😂
Slab edge insulation is very important.
My question ended up on the podcast and thanks for the feedback. I’m going to take out the infrared heaters from the plan. I wanted to address some of the discussion.
The dust collection is externally vented due to recent research that shows wood tools generate micro particles that filters can’t really deal with. Jeff’s point is correct in that it will suck the heat out of the room but I want the air quality trade off.
Propane backup was for when the temps get colder than the heat pump can operate but given the comments on the circulating pump I will swap to propane with a backup generator.
Alexander - we're pondering a similar situation - 24 x 40 garage that would be for 2 cars in front and a wood shop in the back. I'm considering putting pex in the slab, just under the shop section (back) of the garage. This would be serviced by one or two solar thermal panels on on the S wall of the garage. With slab edge and foundation insulation (frost line is 4'), I think this would heat the shop sufficiently (above 40 deg) most or all of the the year. The thermal system would use a glycol solution and thermal-activated pump, without a storage tank. This would be simple and inexpensive system and I suspect very efficient for such a space. Have you considered anything similar?
Also, we have a shop air filter - like this: https://woodworker.com/jdsair-tech-750er-air-cleaner-with-remote-control-mssu-125-372.asp and it's fantastic. I think it's essential in a wood shop and it doesn't require make-up air.