Heating a 24x48 insulated shop

[davewest]

I need to add occasional heat to my shop. It is 2x4 framed, insulated and Im in southeast Idaho with temps dropping to -10 on occasion, but hovering around +15 id guess. For simplicity sake, I am thinking all electric. The only other option is propane, which Im not sure would be any cheaper, and would be more involved and expensive for installation at least.

I wont work in the shop consistently, but when i do, i want quick heat. I am shopping for garage heaters and observed that I can get a single heater, enough for the entire space, or it seems I can get 2 smaller heaters to split the work. Because the space is long and wide, the 2 heater option seems better.

These are just random thoughts Ive had so far, so Im open to feedback. What can you learn me?

Thanks

 

[The Cobbler]

not to railroad your thread, but just a thought...The trouble with "quick heat when you want it" is that when everything is very cold, it takes a lot to warm that up.
you need a lot more BTU to get fast heat than to maintain a constant temp.

 

[Radix2]

What do the online calculators say you need BTU wise to get the temp you want at 15 degrees?

What kind of electrical service is available in your shop? (Amps)

What does quick mean to you ? 1 hr?

 

[astroracer]

"Quick heat when you want it" will also create a LOT of condensation. Every metal surface in your shop will be wet. I tried this many years ago using a kerosene powered salamander. I spent more time cleaning surface rust off the lathes then I did actually using them... I went to forced air heat, keep the stat at 50 degree's when I'm not out there, and set it up to 60 or so when I am. No condensation and all of the tools are pretty warm when I want to use them...
Mark

 

[davewest]

Well let me clarify, quicker heat than a wood stove. Calculations say i need about 35000 btu. That should get me about a 50 degree raise in temp, which should be ok. Real dry up here, terribly dry. I wasn't worried about moisture. Should I be?

 

[csp]

"Quick heat when you want it" will also create a LOT of condensation. Every metal surface in your shop will be wet.

That's probably not an issue in the OPs location. It isn't in CO.

 

[danbuff]

You might want to look for a used kerosene torpedo.. To try.
I have a 115k BTU for 24x36 insulated, and it is quite quick..Stinky, but to get you going on occasions..

 

[davewest]

Im holding off on propane and kerosene. Id rather not deal with refills midwinter etc. Anyone heat their place with electric only? Id like to get an idea of cost.

 

[AirJunky]

Not that this is efficient, but it's easy. Work well in my 2.5 bay insulated garage. Takes 15 - 30 minutes to warm the place up & keeps it in the 50s pretty easily.

I have this patio umbrella heater suspended from the ceiling with a small piece of pc's.

This one is at Costco.

 

[astroracer]

Just sayin'. You go from 15 degrees to 60 and you are going to get condensation. It's physics guys...
Mark

 

[manufacture]

I would recommend what I am running, or something similar, in my 20 x 20 more or less uninsulated garage. A 75k btu forced hot air condensing propane furnace. During Maine winters it is able to get my garage up to a workable 55 degrees in less than roughly ten minutes due to it moving a lot of heated air. I am able to run it off a 40 lb propane provided the bottle is inside the building. The combustion air intake and exhaust is PVC pipe which is easily piped outside and mitigates fire dangers due to fumes from stuff in the garage like gasoline. I managed to find the furnace on craigslist for less than $200 and it has always worked well with no failures. Since the moisture that is a combustion byproduct either goes outside or drains into a jug as condensate I don't have moisture problems on tools or equipment. The only slight pain is the condensate drain itself. I just made a p trap out of brake line that empties into a jug. I just have to remember to empty the trap and dump the jug before it freezes but if I forget I can quickly thaw the trap with a torch and be back running in a minute. My furnace is a thermopride unit.

 

[theoldwizard1]

I wont work in the shop consistently, but when i do, i want quick heat. I am shopping for garage heaters and observed that I can get a single heater, enough for the entire space, or it seems I can get 2 smaller heaters to split the work. Because the space is long and wide, the 2 heater option seems better.

That will cost more, but it will heat the space faster and more evenly. If possible mount them kitty-corner from each other.

Electric heat is cheap to install, but expensive to operate. It will not heat up an area as fast as gas (natural or LP) will. What you want is a through-the-wall/direct vent furnace/heater. Rinnai is one of the top manufactures.

 

[Adk Mike]

Get yourself a Modine Hotdawg HD 60. They run on propane. Get a 100 gallon tank from a propane company . You'll be good to go.
Part time heat in your climate 200 gallons a year max.

 

[n20junkie]

People seem to have a few things inaccurate.

First heating with a source that exhausts combustion gasses outside the building WILL NOT cause condensation issues. Heating the air, regardless of rate will decrease the relative humidity inside the building (warm air holds more moisture than cold air). We warm the inside of gun safes and welding rod storage boxes because heating keeps the relative humidity low.

Cooling after a heating cycle can cause condensation issues as the cooling air increases the relative humidity. This is especially the case if water evaporated during the heating cycle and wasn't vented (melting snow or washing cars inside).



Any combustion source that vents inside the structure will cause very bad condensation issues. Many have tried it, and it makes a mess out of any bare steel.