heater Sizing

[Steve Szakats]

OK, its time to buy the heaters. I have a brand new detached 3-car garage, and an existing attached garage with bedrooms above. The detached garage has 8 foot ceilings, the attached garage has 14' ceilings. FWIW, in winter the bedrooms over the attached garage are cold.

My question is, how many BTU do I need for each garage? All the literature I read says a 45,000 btu unit will easily heat a 2-3 car garage. Do I need to go to a 75,000 btu unit? What effects do the variable ceiling heights have on sizing the heater? How about attached versus detached? I would have thought that an attached garage would be easier to heat than a detached one and hence require a smaller unit. Can I get away with a 45k unit in both garages?

Thanks, Steve

 

[MyDomain]

I would sketch out your garages, including window and door locations, insulation values and orientation. Then get whomever you are buying it off of to do a load calc. You can also do one yourself here. Use the KwikWay application. It is for a high velocity unit but a btu is a btu. Don't forget to check the "Heat" box or you will just get cooling.

 

[Winmon]

Here is a basic guide. Scroll down to "Size you Heater"......

http://www.northerntool.com/catalog/buyersguides/heaters/