convert hay barn to shop

[littleboss]

I have a 60x40' hay barn with 14' sidewalls. I am thinking of converting it to a shop. I would concrete 2/3's of the floor and on one side just leave the gravel. The motorhome and truck would park there.
My questions relate to heating and cooling. With a 5/12 pitch the attic space is huge, lots of air space to heat and cool. The motorhome only needs enough heat to keep it from freezing. I thought I would just plumb it to my propane tank and set the thermostat right above freezing.
Doing this am I better off adding a wall to separate this section then I could just use the motorhome furnace? With the price of tin and steel right now maybe better off to spray foam the whole thing and just leave it open?
Was thinking of installing a couple 36,000 btu mini splits and a hanging propane shop heater for backup.
I like the thermostat around 72 in the summer so I definitely need some cooling capacity.
My other option would be to install a ceiling at 12' in the 2/3's side to save on heating/cooling bills and leave the motorhome side open and uninsulated.

Thoughts?

 

[nadogail]

All discussions of HVAC need to include your location. In my location we have very little danger of having a significant frost.

 

[littleboss]

north of Dallas TX. Gets hot!!!

 

[carlaisle]

Wouldn't winterizing the RV be an easier and more cost-effective approach?

 

[MushCreek]

I know from the experience of trying to heat/cool my barn that high ceilings make heating in particular a challenge. I have 22' ceiling in the great room area, which is insulated and finished, but the minisplit struggles to heat it. I'm sure that up at the ceiling level it's quite toasty. I run two ceiling fans slowly to push the warm air down. Over the shop area, I have a closed loft, so the ceiling is only 12'. I'm currently working on insulation and finishing, so I'm hoping it will be easier to heat. I can handle the summer heat for the most part, but it's tough to run a lathe or milling machine in a 35 degree shop!

 

[littleboss]

Wouldn't winterizing the RV be an easier and more cost-effective approach?

I am converting the hay barn into a shop. RV can either be in conditioned or unconditioned space

 

[NUTTSGT]

Are you planning on heating cooling the gravel area ? You'll end up pulling moisture out of the ground if you do making the HVAC work harder. . . costing more $$.

 

[MushCreek]

Keeping the RV above freezing depends on your climate to begin with. Here in upstate SC, my shop doesn't seem to ever drop below freezing now that it's closed off from the great room and the loft, even without insulation. We've gotten into single digits (briefly) the last couple of winters, but the shop never got below 35. I imagine that once it's insulated, it will stay even warmer. I agree with the above that you shouldn't try to heat/cool the gravel area. Part of the reason my uninsulated shop stays above freezing is that the slab retains a lot of warmth. I looked up Dallas, and see that they have occasionally gotten below zero, although it's rare. Maybe a provision to heat the RV section in an emergency, rather than all of the time? Insulating it will keep those 'cold emergencies' to a minimum.

 

[littleboss]

Are you planning on heating cooling the gravel area ? You'll end up pulling moisture out of the ground if you do making the HVAC work harder. . . costing more $$.

Not sure. Might just wall it off and hook the RV to propane.