Shop heating and cooling

In an effort to keep moving forward with posts that might help folks looking to set up a shop, how do you manage the temp and humidity in your shop? We live near Sacramento in Northern California, so we have hot (90-100*F), but dry (<20%RH) summers. But we have very mild Spring and Fall without much humidity, and our winters are only cold by California standards (40-55*F daytime temps), with moderate humidity. My shop has insulated walls and I insulated the roll up door and most of the roof between the rafters. This, in and of itself, had a huge impact on moderating the temps regardless of what time of year…especially during the summer.

I don’t have any active cooling, but I did install a 20” box fan across the old pet door opening, and another 20” fan on the wall near the roll up door opening. Most of the year I’m able to keep the roll up door open, which moderates the temp when it’s not extreme, but the vent fans do a great job of drafting air through the eve vents I cut in. All the fans are automated through my home automation system. They also reference a motion/temp sensor, which kicks on the fans when the shop heats up. This is really helpful when I’m not in the shop to keep it from warming up too much, and to take advantage of the (slightly) cooler summer nights. 

I do have a small infra-red heater pointed at the workbench, which is also tied to the automation. From a safety perspective, the heater can only activate when the workbench lights are activated through automation. And that can only happen when a presence sensor shows that I’m at home. The infrared heater is great for the small area since it actually warms up objects, as opposed to just warming the air. This makes a big difference when working at the bench. It also references the temp sensor, and has built it shut offs and safeties based on time.

I’ve gone back and forth with putting in a mini-split. I’ve got a place for the unit right outside the shop, and even have a slot in the electrical panel for it…but I really like having the roll up open, which would defeat the purpose. And then summer rolls around and I hate myself for not doing it…

Here’s the exhaust fan on the door…

Here’s a circulating fan…

And here’s the small infra-red heater (upper left)

So, let’s see what you’ve got in your shop to beat the heat!…or the cold…

Ryan/// ~sigh~ I blew up another bowl. Moke told me "I made the inside bigger than the outside".

10 Replies

My shop is under the house (double brick) and doesn't seem to be subject to extremes...
In winter it seldom gets below 12°C which is not too cold for the nightie... seriously, my civies consist of shorts and a medium weight sports shirt which seem to be enough and if it really gets cold some short socks.  Winter is never an issue as I could put on some extra clothes if I had any (don't own any longs).  Also being an ex skier, I prefer the cold.
I hate the heat, but fortunately in summer, even the hottest days, it seldom get over 25°C in the workshop, which I tolerate and if needed call on my Ryobi air cannon,

that will operate from either a battery or mains.
If it tops 26°C I turn on my egg-nish-ner which is squirreled away in a corner...

I've only used it about 1/2 dozen times over the past 8 years, to the point that every time I need to use it I have to RTFM to operate it.

During extremes and if the opportunity arises, I occasionally move small jobs to my office... hence my dependence on my Mini Office Workbench.

If your first cut is too short... Take the second cut from the longer end... LBD

I've got a forced air furnace (sealed combustion) hanging from my ceiling with the duct running across the back wall that does a fantastic job of keeping the shop warm in the winter (MN), and I run an evaporation style humidifier set to around 30-35%, otherwise it ends up in the single digits when it gets below zero outside and the furnace runs more.

When that setup is no longer necessary, I have a dehumidifier with an automatic pump to control humidity, and a dual vented portable AC unit that vents out through the garage door (I cut holes and made a custom bracket for it), for when I need that.  Wouldn't mind a mini split, like everyone will say is needed, but the above gets the job done just fine for me for the time being.  Significantly cheaper than the mini split, and I don't need a lot of cooling, just when it's up in to the 90+ degrees and humid.  I also installed a remote controlled oscillating fan in the corner ceiling near my bench, so even if it's a little warm I can run that and be fine.

I guess one of the advantages of having a small workshop is that it doesn't take much to heat it or light it. I have also insulated the floor, walls and ceiling. Living on the South coast of England as I do (the English Riviera as we like to call it), we get a bit of all weathers but nothing in extreme. My workshop is like a 4-sided pyramid and I started off with just the round LED center light you can see in the following pic. I didn't think that was enough for hand tool work, so I added the 4 LED spots. I will also be adding a couple of clip-on LED lights that I can move around depending on where I need a bit more light.

For heating, I use a tiny oil-filled radiator which is ok, but it takes a about 30 mins to get up to temperature and then about 1 hour before you start to feel the effects of it in the room. I also don't like the fact that it has to sit on the floor as space is at a premium.

I'm considering getting a small infra-red heater mounted on the ceiling once I'm a bit more organized. 

Andy -- Old Chinese proverb say: If you think something can't be done, don't interrupt man who is doing it.

Summertime I use the ceiling fan and have the doors open, so far it has worked out for me. Wintertime I use a small, inferred heater (1500 W) which takes the chill out of the air, might pick up a second one to hang in the other corner.

Main Street to the Mountains

Timely thread. I currently have my small shop space in the basement, which does get chilly in the winter, but isn't challenging otherwise. Recent and prospective equipment acquisitions, along with some upcoming builds, are making the small basement space look less and less practical, though, so I've been mulling over a move to the detached garage (2-1/2 car and we only have one car). 

In MN, that can mean pretty chilly temps in the winter and a decent amount of heat and humidity in the summer, so I've been thinking about how that would affect both my materials and my motivation. I did have the foresight to at least insulate before sheetrocking, and to get an insulated garage door. In the dead of the winter, and with no active heat source other than the car being parked there after a drive, the space tends to stay just a smidge over freezing. 

Because of the biggish air volume, of which I'd only be occupying 1/3 or so, I'm thinking that an infrared heater is probably the short-term, foot-in-the-door heating solution, but I'd be interested to hear what other cold climate folks think. 

For the summer, I really don't know.... I'm not terribly concerned about my comfort level - I regularly exercise to the point of sweating buckets - but I'm not sure how the bigger temp and humidity swings would affect materials, so I'm interested to hear feedback on that, as well. 
Pa. weather is ice cold or humid so bad lucky im under shade trees most hot days and i have heavy duty fan blowing hot air out of roof out the doors and winter i have oil filled rad electric we just had cold snap feels like -20f and it was 55 just with that heater i was happy 😎👍


dI installed a MrCool DIY mini-split last year and love it but does sort of sound like overkill for you.  Before the minisplit, I used a 12k BTU portable AC with heat function to cool and heat my shop and a quartz radiant heater to boost the heat on the coldest days.  If you go the portable route, you definitely want a 2 hose portable AC unit because otherwise, it will simply suck unconditioned air in through any cracks of vents, reducing the efficiency.  I don't have any windows in my garage shop so I added garage door exhaust vents to route the AC hoses through the door for the external air exchange.  The vents are designed for mechanics to vent exhaust pipes outside for running the car engines while the door is closed.  They were a little small but that didn't seem to affect the efficiency of the unit.  I basically replace the hoses with drier hoses with a quick disconnect connector that fit the door vent.   If you have a window or can cut a hole in the wall, a window unit will be cheaper and probably more efficient but the portable unit is a nice option, especially if you will only use it occasionally.  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

My climate in western Oregon is somewhat similar to Sacramento but not quite as hot. My shop is well insulated and shaded by trees.  In the summer it never gets above 75 F (23  C) even after several days in the 90s F (92 C). It cools to the low to mid 50s F at night so if the shop does get warm I can cool it by opening the windows at night.
 In the winter I heat it with a wood stove. It usually takes a couple of days to burn up all the wood scraps I have generated over the summer then I go to my fire wood pile for fuel. I have a custom made air cleaner for dust with a furnace fan in it that blows across the wood stove and circulates the heat. 
One shortcoming of the mini splits is, as with regular heat pumps, that they work best when the temperature is set to a narrow bracket between high and low of say 6 degrees or less 24/7/365.
This year we redid all of the attic insulation including over the garage turned woodshop.  It hadn't been touched since the 1960s when the house was built so we had all that crap sucked out.  They came back in and air sealed with spray foam and then blew 18" of insulation in.  So far the coldest its been overnight this winter is -14 F and the shop stayed at 49 F.  I have a 30K BTU propane heater and within 10 min I'm back up to 65 F.  I think I'm insulated well enough now that I can get by with a 1500 watt infrared and use my air cleaner cart for circulation.

I still need a solution for the summer though.  This summer with outside temps around 100 F the shop stayed around 80 F until I have to open the overhead door and then it gets hot and it stays hot.  I'm considering a Quiet Cool garage fan so I can crack open a window in the late evenings and suck some cool air in while exhausting the hot air.  Its not an ideal solution because i live in KC and it gets humid here.  I have a lot of old cast iron planes in the shop that wont appreciate it but I can run a dehumidifier to help out.  Eventually I want a mini split but I think the exhaust fan would still be useful.  I'm thinking a guy could build a filter box around it and use it as an air cleaner once the mini split is in.
We have a Quiet Cool whole house fan and it is amazingly quiet. Works great during spring, summer (late at night) and fall. I use a box fan sorta the way you’re thinking about, but I installed even vents so I don’t have to open the garage. But we don’t have much in the way of humidity here, which I’m sure could be an issue. 

Ryan/// ~sigh~ I blew up another bowl. Moke told me "I made the inside bigger than the outside".