"window" unit vs. mini-split vs. conventional vs. nothing

[docjay]

New 40X60X14 pole barn with finished metal walls/ceilings
R39 top and R29 sides
Four 72" fans
Central NC...want to keep >50 in winter with work temp of 62-66 and <84 in summer with work temp of 78.
Will use weekends and occasional week night....car storage, race car prep, etc.

Was only going to use a 125k btu NG Modine for heat and nothing for AC

But buddies have said need AC....so thinking of doing Modine for heat and a large "window" unit or maybe two mounted in walls for AC

Or mini-split for heat and cool or

just go with conventional ducted unit in attic.

 

[Milton Shaw]

Conventional duct unit in ceiling would be my choice and then locate the ducts where you are going to be working the most. Don't really need them over the lifts for instance. If those 72 inch fans are ceiling fans they will help in the winter on a slow speed to get the hot air off the ceiling and down where you are working.

 

[docjay]

I think conventional would be ideal but will most likely cost the most.
What is a far price for an installed conventional ducted natural gas unit for new pole barn construction?
I was think 8 vents via two ducts

 

[Ohmthis]

Low to high$$$
Window units- cost of units, framing, and electric, total DIY
2 zone mini split slaved together- cost of equipment, linesets, control wiring, power wiring, and labor is reasonable.
Traditional split- equipment, lineset, power wiring, but labor is greater. Running duct work, insulating it if above the ceiling can take as much as a day. Then the rest of the system can be installed.
Hope this helps give some insight!

 

[Big Daddy Chop Shop]

Conventional split is a good option, always.

A building this size, I would also be considering a Convertible RTU such as the Trane Precedent or IMPACK units. Both are packaged solutions that can be roof or ground mounted. Gas/ electric, A/C only or heat pumps available.