Preparing a shop for sub-zero temperatures

[JPigg55]

I live in west, central Illinois so winters aren't quite as cold as yours, but can get very cold for extended periods.
My shop is built in a 20' shipping container, big metal box although floor is 3/4" plywood. I framed up the interior with 2x4's sheeted with 3/4" tongue and groove OSB and fiberglass roll insulation (floor not insulated). Not near the R value you have and square footage isn't as much, but I can keep my shop comfortable 24'7 with a single milkhouse style electric heater: https://www.walmart.com/ip/Milkhouse-DQ1001-Deluxe-Portable-Utility-Heater-1300-1500-W/136517959
Mine is a selectable 1300/1500 watt or fan only with thermostatic control. The thermostat is crap and heater was short cycling so my solution was a remote thermostat similar to this one: http://www.morelectricheating.com/d...MI_76p0-773QIVUL7ACh2ALwZHEAQYBCABEgLLn_D_BwE
If I were you, I'd definitely seal and cover the concrete floor. Concrete is a big heat sink and wicks moisture.
Laying down a sheet of heavy plastic and cover with some foam insul-board or similar and cover that with plywood (I'd recommend 3/4") would mitigate a lot of this.

 

[ThinWoodsman]

The concrete pad and the barn were built long before I acquired the property. The cost of building the shop already exceeded what I had planned to spend - the insulation and the 3-phase subsystem ate up quite a chunk of change, and lumber has gotten pretty expensive. Ripping out and pouring a new concrete pad would have cost far too much.

I've been looking at putting those interlocking rubber pads on the floor; wouldn't be too much trouble to run sheets of plastic underneath. The machines would still be on the bare concrete, which is why I don't want to seal it - the moisture would just channel up under the machines or in the walls.

Re: the condensation management post, I've been looking at getting some heating pads (the ones used for auto engines and such during winter) for the machines. Sounds like that is the way the to go, and it wouldn't be too difficult to cobble together a humidity control. Really a good idea.

 

[Dabbler]

Too bad it is way too cold here to grow Red River Gum - I live in the Great White North!

 

[ThinWoodsman]

I chucked a $40 Pelonis radiant oil heater in the shop and have left it running at the lowest setting. Keeps the shop at 50, which is warmer than I need, without a noticeable increase in power use (~15 kWh).

The past couple of days have been the real test: lows of 3 F overnight two nights in a row, highs of 13 F during the day, and a 6-hour power outage on the coldest night.

After the power came back on, I went to the barn to check out the shop: temperature was in the 40s despite the lack of heat. A bottle of water left on the floor as a cheap/lazy experiment has not frozen. So the insulation works pretty well, and maintaining a resonable temperature is not a problem.

I didn't get to empirically determine which devices or substances cannot be exposed to sub-freezing temps, but I'm happy with the outcome. The shop can be fully utilized in winter, as long as I can dig out the barn doors.

 

[Boswell]

I chucked a $40 Pelonis radiant oil heater in the shop and have left it running at the lowest setting

This is exactly what I do. I have a relatively small insulated shop and I stash the oil heater between the wall and the lathe where it is out of the way. on the lowest setting, keeps the shop very acceptable.

 

[Downunder Bob]

Too bad it is way too cold here to grow Red River Gum - I live in the Great White North!

Yes i know what its like up there. We have friends in Calgary, they were here visiting just a couple of months ago. You could try snow gum.

 

[Downunder Bob]

I chucked a $40 Pelonis radiant oil heater in the shop and have left it running at the lowest setting. Keeps the shop at 50, which is warmer than I need, without a noticeable increase in power use (~15 kWh).

The past couple of days have been the real test: lows of 3 F overnight two nights in a row, highs of 13 F during the day, and a 6-hour power outage on the coldest night.

After the power came back on, I went to the barn to check out the shop: temperature was in the 40s despite the lack of heat. A bottle of water left on the floor as a cheap/lazy experiment has not frozen. So the insulation works pretty well, and maintaining a resonable temperature is not a problem.

I didn't get to empirically determine which devices or substances cannot be exposed to sub-freezing temps, but I'm happy with the outcome. The shop can be fully utilized in winter, as long as I can dig out the barn doors.

If your barn doors are being snowed in you could cut a normal sized door in one of them and make it a couple of feet off the ground so you wouldn't have to do all that digging.

 

[ThinWoodsman]

If your barn doors are being snowed in you could cut a normal sized door in one of them and make it a couple of feet off the ground so you wouldn't have to do all that digging.

I have an exterior staircase to the loft that provides perfect cover for a door beneath the landing. I considered cutting a door there but decided to wait and see if it was necessary. So far, the work I did on the barn roof and walls caused enough heat to be trapped that there isn't much buildup around the doors themselves.

Now I only have to dig through the berm left by the plow guy

 

[Toolmaker51]

That friend I gave the heater to I also delivered several truck loads of off-cuts from a wood supply company. These were 4" x 2" of assorted small lengths when timber was cut to length and any blemishes removed. I thought I was supplying firewood but he used them to lay down a Parquet floor over the concrete slab, all except for an area where stuff like bulldozers or other vehicles go to be worked on. Glue was the only cost and it is great insulation, very hard wearing too.

Floors, a favorite topic of mine.
The greatest shop flooring possible is what some term Parquet. That is wood, grain laid horizontally, the alternating criss-cross pattern is more an efficient use of small materials.
Not the worst, but not what I consider ultimate; good photos of early shops show how widely accepted the alternative was.
That goes by a few names, but 'wood bricks' is one; difference is they are installed vertically, exposing endgrain, usually mix of 2x4, 4x4, and 2x6. 8's or 10's can be used, but more prone to cupping, being material closer to middle of timber I suppose. Nothing but radial arm or miter saw and a maul with a fair sized head. Depending on your underlayment or slab, a drum floor sander will even things up.
Too early for posting shop pics but machines are in place. I'll frame around them and start in one corner.
Heat sources, another topic worth consideration.
Here in the Midwest, close to exact center of USA, we don't have long severe winters, there are short intense periods. My building is about 125 years old, former factory building with foot thick red brick walls, fairly thick cement floor, above grade (loading dock high), all windows are glass block, leaving only the doors to improve. Learning where roof leaked from rain, turned into weather science complete with frozen buckets of water.
Season after season went by while looking into varied heat sources, with this conclusion. In our zone, the only reasonable source for spaces containing machinery is radiant heat. Infrared is one, some fuel burners are, but anything blowing is not. Forcing air causes it to rise, without changing temperature of machinery. That iron is a temperature energy storage mass, that only radiant can alter effectively.
This space will be natural gas hot water boiler and cast iron radiators, at around 350k BTU, once ceiling trusses are enclosed, and blowing mountains of insulation.

 

[Bob Korves]

Move the shop to a warmer climate. Our family left Pipestone, Minnesota for Sacramento, California when I was a 8 year old boy. Best thing that happened to me in my life. I loved snow, winter backpacking, cross country skiing, downhill skiing, and other winter sports during my school years and later here in Sacramento, but drove up to the Sierra Nevada mountains for a day, weekend, or a week enjoying winter, then drove back to Sacramento, where it might go a couple degrees below freezing over-nite on a few nights in an entire winter. My shops here have not needed heat to keep them warm, just an old jacket on the coldest days here...