Garage Heater

[gsea]

Just purchased my first home and have gone to work setting up the garage. As winter is starting to roll in, it will soon be to cold for all my winter projects without some type of heat.

The garage is an attached 21'x19' with 11' ceilings. I have natural gas to the house, as well as 220V service, though neither are in the garage at the moment.

It is built into the house and is therefore partially insulated (on 2.5 sides). I don't plan on staying in this home for more than a couple of years, so my ideal setup would be minimally invasive/removable. It would be great to have it consistently heated, but really I just need to fire it up to work on projects a few nights and on the weekends.

Winter temps usually hover around the 20-30 def F range, though they can dip into single digits for a few weeks.

I've been leery of forced-air heaters since I live in a dusty area and already have issues with that. Blowing it around further didn't seem like a great plan.

1) What type of heater do you recommend?
2) How many BTU will I need to keep it a cozy 60-65 deg?

 

[Cyberbear]

Since you are not comfortable with forced air type heaters, have you considered infra-red space heaters? Those who manufacture these can provide heater sizing for your needs.

 

[gsea]

Yes, I have considered them, and am wondering if anyone can chime in with experience. Since they heat objects rather than the air, it seems you would want to be very strategic about placement.

Another concern I had was the water vapor produced as a byproduct of burning a gas. Has anyone had any issues with rusting tools or mold/mildew as a result?

 

[warren57]

Size.... 20-30 btu per sq/ft. Output capacity. (12,000 btu output)) (Dependent on construction, insulation, openings, etc.)
Lowest operating cost.... Radiant nat gas. But not a very even heat.
Nat gas unit heater. Yep that's the one.
No nat gas.... Electric unit heater. Higher operating cost, need lots of power. And of course convert btu to kW for sizing. 20 btu= .00586 kW 30 btu= .000293 kw ... 12000 btu= 3.516 kw or a 3.5 kw heater would likely do it. Again tightness of structure, materials of construction, size of door and window openings as well as r value of both, insulation r values, floor materials, etc. all play into amount of heat required. And temp in and out of the heater will determine how fast it will get up to that 60-65 degree set point.
Hope this helps...

 

[gsea]

Yep, sure does!

I've decided to go electric forced air. I do have natural gas, but it would be a lot easier and cheaper to run a 30A electric circuit to the garage than install and vent a natural gas heater. The other concern is that I'd like to it to be somewhat temporary as I will only be living in this home for a few years and then it will become a rental. I don't want the liability issues of providing a natural gas heater....