A/C for garage

[Jon_E]

Looking for opinions on what would you do re: A/C for garage. I am in New England, can get hot here, supposed to be 90°F+ this week, 60's at night. Too hot for me to work even in an enclosed and shaded space. Would like to get garage temp in the low 70's and DRY. Lower if possible, my house basement stays between 66° and 69° just from the heat pump water heater. Humidity is my killer. I have 24x36 space, second floor loft does not need cooling, just the main floor. Insulated to about R12 in walls, R20-ish in ceiling. Will hold heat/cool fairly well. I have limited budget.

Was wondering if a simple 30-pint dehumidifier would help at the most basic level. Next step up would be a new, not used, Energy Star A/C unit which would be more-or-less permanently mounted in a wall sleeve. I'm thinking 8K BTU. Last resort due to cost would be a DIY MrCool heat pump. Any other options? Dry is key, the space is primarily used as a wood shop and de-humidification would help with the introduction of "less-than-dry" stacks of lumber on occasion.

 

[Marctrees]

Seems to me off the cuff that with that sq footage and meh insulation a window/ wall AC 8k is way way too small...definately need 15k minimum.

Marc

 

[DHCrocks]

dehumidifier will make it slightly hotter in the room. If you only want to control humidity then this would be ok, but since you're looking to cool the room that is definitely not going to work.

I agree 8k is way too small.

 

[James-W]

I would go with at least a 12K BTU and preferably 18K BTU air-conditioner if you don't run it all the time. If you run it only when working out there, it will take awhile for a smaller unit to remove the moisture and cool the space down. The larger units will cool the space faster and remove the water quicker.

On the other hand, if you run the air-conditioner all the time you can use a smaller BTU unit since it will running full time and won't have to cool down the space and remove the humidity from scratch.

That's my opinion of the matter.

 

[dmcintosh]

I used a 25K BTU window style in my 24x30 garage and was very happy with the way it held temperature. Ima little further south (Delaware) so maybe you get away with a smaller unit, but IMO it’s easier to turn the thermostat down than not have enough cooling capacity.

 

[BillK]

I have a friend with a similar size detached garage and he has a mini split for heating and AC. If I ever decide to heat and cool my 24x24 detached that is definitely the way I would go. A little more initial expense but I think it would be well worth it.

 

[Showkey]

My 1000 sqft shop in central Wisconsin is well insulated and in the shade. We average 1 to 12 days in the 90* plus with high humidity per season. We are in one of those heat waves this past 10 days.

My shop is closed up doors and windows closed. Inside Temperature Usually stays below 75* and I run 50 pint dehumidifier maintaining 40-50% relative humidity. Without the dehumidifier humid levels were above 75% causing mold and mildew to form on organic materials.

My shop was built with AC wall mount and wired for a large unit. I am the third owner, AC was never installed. Home next door was built by the same first owner for his son. That shop has AC but the current owner pulled the unit and did not replace it.

Part of my success Without air is shop is sealed, minimal come and going, well insulated, building in 100% shade, slab temperature remains low acting like a cooling coil. Takes the entire season for the slab to warm up.


The morning temperatures with humidity levels,



OP if your garage is out in the sun and interior temps are in the 80*plus dehumidifier will not make it colder, slightly more comfortable........Yes...but far from ideal on those HOT days.