Btu calculators

[Fibersport]

New member here -
Just picked up a St. Croix SCF 050 for use in a workshop/pole barn. I checked the Btu rating of the SCF 050 and find it to be listed at around 45,000. My building is 30 x 54 with 10' to the bottom of the trusses. Right now there is no insulation but a ceiling and walls both with insulation are in the works. Anyone know what kind of performance I can expect from this unit in a building my size? Keep in mind this is all new to me. I don't plan on keeping the building very warm, probably in the 60-65 degree range when we are out there, and unheated when vacant. My question on the Btu calculators is what is the temperature they are saying can be maintained? Literature for the SCF 050 also say it is good for up to 1800 sq ft which I'm under, but the calculator says I need 50K which is more than the unit is listed at. I know these numbers are all really close but the armchair designer in me is working overtime on planning and analyzing.
Thanks - Greg (aka Fibersport)

 

[johneh]

I do not think that a building that size with no insulation
will heat with any stove Good luck
If the building were well insulated and tight you may keep it
warm but would want ceiling fans to keep the heat down

 

[zrock]

with no insulation in the ceiling you will be lucky to get it warm at all. Even if you could go and toss up the vapor barrier up in the ceiling it will keep some of the heat in the building

 

[Seasoned Oak]

with no insulation in the ceiling you will be lucky to get it warm at all. Even if you could go and toss up the vapor barrier up in the ceiling it will keep some of the heat in the building

I agree and 65 is a lot to ask for here. I have an 18 x25 shop and it s takes awhile to warm it up with a wood stove and a coal stoker (total of 150000BTUs) going at the same time. Heating up a large shop from cold probably take 2 or 3 times the BTUs as it does to keep it warm once its heated.

 

[mikkeeh]

Keep in mind...those numbers are for an insulated space....and typically with 8” ceilings. With 10’ceilings, you are adding another 3000+ cubic feet of space to heat. I heat a 24x24 space with 10’ceiling....R24 in the ceiling, and R8 on the sidewalls with a 5500M. Not sure but i would guess its rated at about 45k btus. Once the building gets cold..it takes a couple hours to get comfortable..ie 60-65. If its really cold out...like in the teens....will run prett hard on level 3 or 4 to keep up. So I’m heating 5800 cu/ft of insulated space, and you’re talking about heating 16,200.

 

[Fibersport]

Not really what I wanted to hear but sort of what I expected. Keep in mind I probably should have said "after I insulate", I've tried a torpedo heater rated at 125K I think and it only warms me if I have it blowing on me even though it melted all the snow off the roof with no problem! I am slowly putting in ceiling joists so I can put up a vapor barrier and drywall, I intend to insulate to around R30 - 40 depending on what I can get with about 8" thick blown in. The walls will eventually be about R19 but all this takes time and money. I have actually thought of hanging visqueen to close off the ceiling quicker, maybe I can hang a "wall" of it too and close off half the building.

 

[railfanron]

Go as high as you can on the insulation in the ceiling. My workshop is 24 x 40 x 10 with a vaulted ceiling and a 100 sq ft off shoot and I heat it with a propane furnace rated at 60,000 btus. It's insulated well in the ceiling and r13 in the walls. I can heat it up to 65 degrees in about 2 hours from 30 degrees. The furnace is ducted and I use a big fan to blow the heat down from the top of the ceiling.
Ron

 

[Seasoned Oak]

I have a small shop 18 x 25 and a large shop 24 x 60 I don't even try to heat the large shop. It takes 150000 BTUs to heat the small shop to 60 in a few hours. Once it hits 70 in the small shop I let the excess heat into the large shop but really don't make a dent . Until you get that place insulated you are fighting a losing battle. Eventually ill hook up a 200000+ Btu oil furnace I have to make a difference in the big shop,but for now I just don't do much in there when its really cold.

 

[Fibersport]

I was going to put up a ceiling and insulation before getting anything for heat other than my torpedo heater but the St Croix furnace was what I thought a pretty decent deal that I couldn't pass up, sometimes the horse HAS to go before the cart!

 

[Seasoned Oak]

45000 BTUs even in a insulated space will take a long time to warm up IMHO .