How are you keeping your shop cool?

MMCO

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I am temporarily in a smaller two car garage, about 380 ft.² I live in Colorado and the humidity is generally low, below 30%. I have a large oscillating fan that doesn't do much so I just bought a portable AC unit. It's 17,000 BTU so I thought it would be sufficient. I also insulated the builder grade garage door prior to adding the AC. Today was the first run. I started it around 2:30 when the temperature was 88°outside. The garage temperature was 85°. I ran the unit on high for nearly 4 hours and the temperature dropped 3°, barely noticeable. Since I'm living here temporarily, adding a mini split is not an option. Has anyone found a powerful AC unit that actually works?
 

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My shop is a hobby shop and in the garage - which means that I have fans and open garage doors. Very nice on nice days, but brutal on hot days - like this past week when we were 97F with high humidity. I've thought about a mini-split, but since it's a big garage that gets expensive quick. And since the doors are closed during the winters, I want to utilize the daylight of open doors as much as I possibly can.
 
Ive just got 2 wall fans that run 24/7.
One is 600mm, the other is about 1200 on opposite sides of the shed.
The giant panel door gets opened when im spending the day or afternoon in it, that helps.
I have also gone and installed bubblecell insulation across all of the C purlins ( wall to wall, front to rear) - that made a massive difference in the heat.

My temperature/humidity device that lived in my shed died before i finished the insulation install, but i know its much much coolcer than it was before you can feel the difference.
I do remember it sitting on or over 45 degrees C ( no insulation) before opening the windows, and door, and i have joked to my wife about putting a great big split AC in :)
 
I am temporarily in a smaller two car garage, about 380 ft.² I live in Colorado and the humidity is generally low, below 30%. I have a large oscillating fan that doesn't do much so I just bought a portable AC unit. It's 17,000 BTU so I thought it would be sufficient. I also insulated the builder grade garage door prior to adding the AC. Today was the first run. I started it around 2:30 when the temperature was 88°outside. The garage temperature was 85°. I ran the unit on high for nearly 4 hours and the temperature dropped 3°, barely noticeable. Since I'm living here temporarily, adding a mini split is not an option. Has anyone found a powerful AC unit that actually works?
My guess is that you need to run it for much longer to get the temperature down to what you want. There is a lot of thermal mass you need to overcome. Try running it for 24 hours and see what happens.

Bob
 
My strategy for the a cool shop (can get to 115 here on the Central Coast of Cali) is simple: Get in there early and work before it gets hot, then do something else the rest of the day. :cool:

I'm in an unconditioned steel building, walls are now insulated R-20 up to the 16foot level, but haven't got to the ceiling yet. Still, the two rollup doors will make it impossible to keep the heat (or cold) out. We can drop to 20 degrees in January. I just work around it.

Quick aside, when I moved to Denver in '87, the headline news (well, BELOW the Bronco's news) was a week of temperatures in the 90s (August). This was noteworthy. Hardly anyone had (or needed) air conditioning. By the time we left in '06, we were seeing triple digits in May sometimes........
 
My Arizona garage can get hot for sure. I retrofitted foam into the steel garage doors and that helped a lot (I believe you did the same). In my case, I got a mini-split installed, but the key that may work for you is that I put the blower such that it blows directly across the front of the benches. So even when it's hot in there, the cold air is blowing across where I'm working. Initially, yeah, when I walk out of that zone, I can feel the difference until the unit catches up, but it's honestly fine after even a brief period of time. That said, try putting the blower so it vents across the front of your benches.
I also tend to work in there after sunset. When the sun is beating on the garage door, the A/C definitely has to work harder to catch up. Still workable during the day with the air pattern.
 
I have a Mitsubishi mini-split in mine, along with a small fan to help move it around more. It took quite a bit of insulating to make it viable though, a powered vent fan to blow the heat out of the attic made a big difference too. My shop is a nearly 100 year old garage. It was originally a single-car, detached unit, that was remodeled in the 50s. I am currently in a big push to get it ready for my upcoming retirement.
Once I get the walls painted, I'll probably start a build series, showing how I bring home my tools and set-up the new shop. That way it's more about layout than "construction".
 
Quick aside, when I moved to Denver in '87, the headline news (well, BELOW the Bronco's news) was a week of temperatures in the 90s (August). This was noteworthy. Hardly anyone had (or needed) air conditioning. By the time we left in '06, we were seeing triple digits in May sometimes........
There's a message in that statement that needs to be heard and understood...and not just dismissed. (y)(y)
 
My shop is about 1000 sq ft / 93 sq meters and I had it built purposefully to be my long term shop. Heating and cooling were central to my design. To start I set my ceiling height to 9 1/2 feet (2.9 meters). This limited the volume of space which needs to be conditioned. I then used open cell stray foam on the walls and added plenty of insulation in the attic space. I picked an insulated garage door and good windows. I added ductless mini split to condition the space. In the summer I set it at 77 or so and let it run all the time. On humid days I switch it over to de-humidify mode for an hour or so from time to time. Works great for me.
 
I am temporarily in a smaller two car garage, about 380 ft.² I live in Colorado and the humidity is generally low, below 30%. I have a large oscillating fan that doesn't do much so I just bought a portable AC unit. It's 17,000 BTU so I thought it would be sufficient. I also insulated the builder grade garage door prior to adding the AC. Today was the first run. I started it around 2:30 when the temperature was 88°outside. The garage temperature was 85°. I ran the unit on high for nearly 4 hours and the temperature dropped 3°, barely noticeable. Since I'm living here temporarily, adding a mini split is not an option. Has anyone found a powerful AC unit that actually works?
Portable ACs aren't real efficient and they're even less so at higher altitudes and since you're in Colorado where the humidity is very low, you'll want an evaporative cooler. DIY one for around $50 plus bagged ice.

 
Up here in the north, we have these things called basements. The usual location for the shop.

Makes for a real pain when you need to bring your new jointer down to the shop, but my shop stays at a consistent 70F in the winter and moves up to a consistent 71F in the summer :).
There are HVAC ducts run into the basement, but the basement registers are all closed and return vents all blocked.
 
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Up here in the north, we have these things called basements. The usual location for the shop.

Makes for a real pain when you need to bring your new jointer down to the shop, but my shop stays at a consistent 70F in the winter and moves up to a consistent 71F in the summer :).
There are HVAC ducts run into the basement, but the basement registers are all closed and return vents all blocked.
That does work out well for some people, but as you noted, there are issues. Not only is the entry of tools/machines very difficult, getting the projects that you make back out can bring challenges too.
My house is pretty old, meaning that the "basement" was never intended to be anything other than a place for a coal-fired furnace. The ceiling is only 6' high, not much more than a root-cellar.
The ideal basement shop is one with a walk-out.
 
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