Heating your shop/garage

[JoeKan]

I don't have a shop, only a 1.5 car garage and I would consider myself a novice on the 1st level of auto body but I love doing this kind of work. I'm thinking ahead to winter and my wife is going to take back her garage so I can't pull my 68 in it. I do have a place where there is a 2 car garage with plenty of room and a 12 foot ceiling that I can use during the winter months.
My concern will be heating it and I am wondering what all you use or could recommend in heating this garage. I would prefer a 110 volt although I know that it would cost more. Thanks for any help.
Joe

[sweetk30]

modine hot dawg nat gas / propane heater unit .

love it . quiet for size / lots of heat / solid unit .

i have a big shop and run a 125k btu unit and leave the shop at 55* and kick up as needed . if to cold i fire up the wood stove .

[Jrainman]

what ever you decide for that space your biggest problem is the 12ft ceilings unless the garage ceiling is insolated , 80 percent of the heating sorce you use will end up above 8ft .

[joe dirt]

I have a pellet stove in my shop...works pretty good

[Dead Parrot]

If it is not insulated, prepare to be cold. A 120V heater will be little more then a hand warmer. You need to be thinking in the realm of 20~40k btu and that is just for basic not freezing heat. Electric means serious 240v current.

Assuming it isn't your garage and just a loaner space, best bet is probably one of those radiant heaters that fits on top of a 20lb propane tank. Won't really warm the garage up but might make the space where you are working better. Pair with a battery operated CO detector just in case.

Old carpet to sit or lay on when doing on the ground work really helps. Amazing how fast cold concrete pulls heat out of you. Shag is better then the outdoor stuff.

[mongocanfly]

I agree 110v is not gonna do anything...gas is the way to go...we use torpedo heaters at work but you need ventilation...if you use any type of gas heat get yourself a carbon monoxide alarm...you sure dont want to wake up dead...

[JoeKan]

Great advice, I may have to abandon that "great" idea I had because of how much it would cost to heat it.

[Dead Parrot]

I wouldn't totally give up on it. A closed unheated space out of the wind is a lot better then an exposed driveway. You may have to time your garage visits to those days where the temps are above your magic 'too cold' number.

[flashed]

I have a Propane Gas chicken house furnace in mine , think its 250,000 BTU , hangs in the middle of my 34x48 shop and I can only leave it on about 30 minutes at a time . It gets warm very fast , its also very efficient .

[Nut Case]

Dead Parrot has your answer, I use that system, I only have it on when I in there working, and takes enough of the edge off to be ok. Done this for two years and my cost per year is approx 125-150 per year. Make sure you have a C0-2 detector, and that there is nothing your working on that can't freeze.

Nutz

[nlped]

I can’t help you here. I live in the southeast, and it gets so damn hot here that I added a heat pump system to my shop. So, as a side effect of my a/c install, I have heat that works fantastic for a really decent price.

[Overdriven]

I have one of these in my 2 car garage, got mine at Home Depot. I’ve added some insulation to the walls but nothing above, still deciding how to finish it off and maintain access to the storage up there. Anyway, it’s 70,000btu, 5 gallons of kerosene lasts about 7 hours and it’s quiet, I can’t stand listening to those torpedo heaters. I normally put a scrap of 2x4 under my garage door to provide ventilation and can comfortably work without a jacket/coat on when it’s 30 degrees outside.

I brought it to work once when it was single digits outside and had to work inside the box of a box truck. We left the door open 6 inches, turned it on and had to work in our t-shirts. Funny part was putting our layers back on before shutting off the heater and being colder inside the shop than we were in the back of that truck!

[Ziegelsteinfaust]

As a HVAC tech I have serviced quite a few of these things, and in you case this maybe a very efficient way to keep the garage warm.

That is hydronic heating. You basically put a tap on the outlet line of your hot water heater, and another at the relief valve near the bottom of your tank. You use a recirc pump to move water, and a heat exchanger or radiator to give off the heat.

They have issues like recovery is quite slow, but once warm they will keep you place that way.

Use aqua pex for the water lines as copper has a tendency to get pin holes after 5-10 years.

[Greasey Harley]

I live in North Idaho, My shop is an uninsulated steel building, no heat and extension cord power.
I can't really heat it as the tin will sweat in the cold, and condensate inside the building. Right now, I''m just glad to have a concrete floor and a roof

I've been working on insulation, I will probably use a natural gas Reznor with wood backup, if I ever finish my shop. In the mean time
... I use an unconventional heat source:

Seriously though, I love a wood heated shop.
In the dead of winter, I'll keep the gas heat at 45 degrees, and use wood if I want it any warmer than that.

[sweetk30]

Originally Posted by Greasey Harley

I live in North Idaho, My shop is an uninsulated steel building, no heat and extension cord power.
I can't really heat it as the tin will sweat in the cold, and condensate inside the building. Right now, I''m just glad to have a concrete floor and a roof

I've been working on insulation, I will probably use a natural gas Reznor with wood backup, if I ever finish my shop. In the mean time
... I use an unconventional heat source:

Seriously though, I love a wood heated shop.
In the dead of winter, I'll keep the gas heat at 45 degrees, and use wood if I want it any warmer than that.

thats my shop almost to a tee but i got 100 amp service and insulation and modine hot dawg unit . having a few skrewball p.b.whiskey shots as i surf and type here .

[A1971Blazer]

This is the heated area of my garage 20 x 36...the sliding doors lead into the unheated part....
Walls are R19...ceiling will be R30+...
I use this 5000/7500 BTU electric heater from Northern Tool
At 25ºF outside it will keep it at 65º on the low setting a about ¼ of the way on the knob
When I get the ceiling insulated...it should work just fine....
(I still have a few loose ends to finish up on)

[68c10airstream]

I live up north, winters are cold but not a lot of days below zero. As a past auto mechanic sick of dealing with rotted out heat exchangers from solvents, carb cleaners, paint fumes being sucked up into the inside in 3 different repair shops. The heating industry calls it "halogenated hydrocarbons" and warranty null and void (quoted from grainger catalog under unit heaters}.

My option for safe (no explosion potential and no carbon monoxide poisoning potential) is a sealed combustion counterflow house furnace. 96 percent efficient, and it pumps the heat on the floor.

I make a stand so it sits about 2 feet above floor level(code is minimum18") and box it in and put 2 6" 90 degrees elbows on the underside pointing out horizontally. I make a box on top for the return air filters . My current shop is 40x40 with 12' ceiling, metal pole building, metal on ceiling with cellulose insulation above and spray foam on walls (this way when purchased used a year ago).

Just took a temp gun and shot the floor, objects, and ceiling. Floor 57 degrees, objects 60 degrees and ceiling 58 degrees, thermostat at 61 degrees. Ceiling is at r-38, 15" of cellulose.

This is the 5th garage i've been involved with installing a counterflow furnace and ony positive comments. i tell the owners to pump safe warm air on the floor and it will take care of the rest.

Goodman brand furnace is about $1,000 plus extras. I find a steel bed frame for the angle iron and make the stand out of that. The furnace sets down inside the angle iron so it can't shift and slide off. The flange where the headboard mounts become the feet, etc. Some may say this is overkill, but if you are killed from carbon monoxide or an explosion i bet your parents are too old to make another one just like you after the funeral These paragraphs should at least get you to think twice. Good luck!!

I should add that sealed combustion has one pipe that allows outside air to come into the furnace for combustion, and another pipe dumps the furnace exhaust outside! A gas tank leak in a sealed garage will be affected more from a spark from a light switch when you come in the door more than the sealed furnace!!

[LS short box]

If I was going to build a new shop I would do in floor heat. The body shop where I did the body work on my C10 had in floor heat and it was fantastic. No fans blowing dirt around. No noise. The floor was a treat to be near since the temp was set at 70 degrees.

[Jrainman]

Originally Posted by LS short box

If I was going to build a new shop I would do in floor heat. The body shop where I did the body work on my C10 had in floor heat and it was fantastic. No fans blowing dirt around. No noise. The floor was a treat to be near since the temp was set at 70 degrees.

Yep agree thats what I did in my 30x40 Put in pex tubing in before I poured the concrete floor , I use a 40 gallon electric water heater with a boiler aqua stat and taco boiler water pump to control the temp and water flow ,nothing beats radiant floor heat .... and very cheep to run.

[derotoreut]

In your case I would recommend a Modine ceiling mounted heater, either nat gas or propane. I have one in the back part of my shop, which is 40'x40' with 10' ceilings. It draws combustion air from outside and not inside, which is good. It serves the purpose for that part of my shop.

The front part of my shop is 46'x48" with 14' ceilings. For that part of my shop I installed in-floor radiant heat, which I absolutely love. Heat comes from the floor and works its way up. My feet are never cold. It was tricky because I installed a 13' BendPak lift and I had to be sure ahead of time that I knew exactly where the PEX tubing was, so I didn't hit a tube. Worked out perfect for our cold Buffalo, NY winters.

My in-floor heat system with Navien condensing boiler.


Before I installed my lift.


After installation of my BendPak lift.

[burnin oil]

For the radiant heat guys. What do you spend to run the water heater per year? I am about to build a shop myself and want radiant heat. Ultimately a wood boiler setup but that part would be a couple years down the road.

[derotoreut]

Originally Posted by burnin oil

For the radiant heat guys. What do you spend to run the water heater per year? I am about to build a shop myself and want radiant heat. Ultimately a wood boiler setup but that part would be a couple years down the road.

I can't put a number on it, but mine is not a water heater. I'm using a condensing boiler. My boiler will not only heat the loop for the floor, but also provide domestic hot water. It is very efficient. Using a hot water heater vs a boiler for radiant heat is controversial subject. I'm not here to steer you one way or the other. There are many factors that go into the decision making process, so I would suggest you do your research first.

Many boilers and water heaters are not efficient enough to condense the flue gasses down to water. Most boilers and water heaters would rust out or otherwise corrode if condensation occurred within them. For reasons of long term cost and energy efficiency I would recommend using either a high efficient condensing boiler or condensing water heater for radiant floor heat.

[burnin oil]

Thanks. Just scouring the net I get all kinds of answers and numbers. The shop is getting built this year and hope to do some work to the house the following year. Once those are done I want to get the wood boiler setup and heat both. Knowing how plans go the shop would only be on electric heat for 3-5 years before cutting over. I have the shop plans so now i have to clear the land and settle on the amount of insulation under the pad. Just got to finish a few small projects when it's not raining before breaking out the chain saw.

[Bubba4spd]

Dero, what a wonderful space to work in you have!

[macstaples]

Originally Posted by burnin oil

For the radiant heat guys. What do you spend to run the water heater per year? I am about to build a shop myself and want radiant heat. Ultimately a wood boiler setup but that part would be a couple years down the road.

My shop is 1000 ft^2 with 10' ceilings and with all four walls exterior. In the winter I keep it at 57 degrees (to me the radiant heat feels about 10 degrees warmer than what it's set to).I have an off-peak electric boiler and pay $0.045/kWh. My biggest bill was in February of 2019 and I paid $90 for heat when the average temp was 6F. For an entire winter, December-March it averages about $70/month.