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We have a seperate , from our rear workshop , 3 car garage about 600 sq ft . What are you using to cool and dry your garage workshop . Summers here in central OK are hot an sticky. Not really sure what to buy ? Thank you.

I built a small open plan house (long before the "tiny house movement") the first floor of which is about 625 sqft. We cool it with a large window air conditioner mounted high in the wall. We only cool it when we are using the space and it only takes about an hour to bring the temperature down from a sticky 90 degrees to a comfortable 70 degrees. A couple of fans can help circulate the air. The AC unit is over 20 years old and if it were to die I would consider a mini-split or small heat pump to replace it.

Tnx clay I have 3 windows , but thought those window air conditioners were old school. How many btus would I need to cool it to about 75 deg. Thank you

As a general rule (20 BTU/sq ft) you would want one around 12,000 to 14,000 BTU's depending on how quickly you want to cool it down and how hot the ambient temperature is. I'm sure there are those on the forum that can give you better information knowing the particulars of your situation. That calculation doesn't take into consideration ceiling height and is based on square feet rather than cubic feet.

I would suggest a ductless mini-split, probably 1.5-2 ton.
Simple install, though you need an HVAC guy for the final evac/charge.

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My memory is so good, sometimes I remember things that never happened.

Tnx clay , the ceiling is maybe 8 ft high windows are at 3 ft. ,. I/m guessing 12 k BTU is good . Eh hoser, Brian I know it gets pretty hot in the summer from osoyoos to vernon. But the okanagan is a lot dryer than here in OKC ok. Its mostly hot humid gulf air,which surprised us. We have been here 6 mo . even the winters are damp and cool with high humidity compared to the low humidity in winter in Missouri .. Will check into the mini split. Already have a good heater for winter. Thank you !!

Hi Ernie,
If you have a good heater, then a window AC might be all you would need. I heat with electric resistance heaters - not the cheapest option in the long run, but low initial cost and easy to install/ replace. A small heat pump or mini split might be a better option for heating and cooling.

A couple of thoughts on cooling a space.
Consider the insulation values of the room (walls, ceiling, window area & type (single or double pane), and don't forget the garage doors. They can be poorly insulated and drafty. When you decide how many BTU's you need keep humidity in mind. AC units all remove humidity thru condensation on the coils. A large unit will cool it down quickly and then shut off. A smaller unit will run longer to cool but that is good in high humidity, as it will remove more moisture from the air getting to the set temp, than a larger unit does.

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Joe Beaver
Maker of Sawdust

I have a 400 sf garage/shop in Houston and use to have one in Tulsa, so I am familiar with your conditions. I have a 10k BTU air conditioner which is sufficient. You have half again as much area so 14k would probably work well. I also have a 70 pint Frigidaire dehumidifier, which works great and is totally necessary in this climate. Also, one thing to really consider is sealing your floor with an epoxy paint to prevent moisture from coming up from the ground. Also, make sure your garage doors are insulated and sealed around the edges.

Hey everyone tnx , No the floor is not sealed . but I sealed and insulated the garage door, The large shop heater works very well. But sealing with epoxy paint sounds like a good idea . There is a lot of humidity around especially in the mornings , and drys off in the aft. Going to check for a ductless mini, although they do seem pricey and perhaps a the cost of a used 14 k wall unit, I also have a 70 pint dehumidifier. Thank you !

I would not get a used air conditioner. They wear out in a few years and are considered disposable now. People do not get them fixed. Go to a big box store and get a cheap window unit with an extended warranty. Count on replacing it in 6 to 8 years.

Tnx for that timely advice Barry

I have a 3 car garage shop, but I walled up one car bay to be isolated from the other 2. My bench is in the single walled off bay, and I store guitar wood and work mainly there. This way a simple rolling dehumidifier, a small electric heater, and a small rolling AC robot are all that is needed for that small space. On dry days, I hang up damp towels. The machines are in ambient temps and humidity, and here in San Diego that is rarely a problem.

Just an idea to only control the area that is needed to be controlled.

Tnx SDiego, is very nice an dry. The perfect place for luthiers to live

From what I understand concrete slabs give off a lot of moisture so sealing it is probably a good idea. I like the idea of a minisplit too. I don't have a garage shop but my shop has a minisplit. It was a DIY install mini too so it was lot cheaper then having installers put in a Mitsubishi for example.

Ernie, my car garage is converted to a workshop, 675 sq/ft. I cool it with a Frigidaire 15,100 BTU AC unit, a small de-humidifier, a whole house humidifier and a Mr. Heater propane heater. I live in NC and temps get to 100's in summer and teens in winter. These keep the shop temp comfortable and the humidity at 40-50%.

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"I've been had again"
Tim Benware
Creedmoor, NC

Thanks for taking a pic Ben, and showing us your stuff. I/m off this am to get another ridgid vac my old one blew up 2 weeks ago at my other shop in lees summit . I will definitely check out what they have at HD an lowes this am. We already have 2 heaters for the shop and a dehumidifier,. a fridge should make it pleasant to work in !!

The extra filter Tim has taped to the front of his AC unit is a good idea. No matter how good your dust collection, your AC unit will pull in a lot more dust than it would in a home environment.

Tim, what kind of material are you using for that A/C pre-filter?

I got a 2 ton unit in my shop.

Problem is the walls are basically corrugated sheet metal, and has crap R value (I can feel heat through the wall during the day) and the AC just runs and runs and won't cool the room below 90 even when it runs.

I don't feel like spending a ton of money on tin shacks but I do need to at least make the space cool-able. I have a roll up door in front of the shop that is drafty as hell and has holes in the door for ventilation. I covered it with plastic tarp.

I am thinking maybe if I divide the shop in half with plastic tarp, and put fiberglass insulation on the sheet metal walls it would perhaps improve R value quite a bit?

The roof is sheet metal too but it's insulated roof panel. Insulation material is not cheap, 30 dollars for .5m x 10m x 5cm. I'll probably need several of these to at least cover the wall that's facing the sun during the afternoon.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Dryer sheets. can't remember where I got the idea but it works great, Mine are ready to change - can you tell!!

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"I've been had again"
Tim Benware
Creedmoor, NC