shop furnace

M E Cook · Dec 4, 2016

do you think a propane furnace 40000 btu will heat my shop 24x36x12 ceilings insulated with 3 1/2 rigid in walls r30 blown in ceiling need to get to 60 -65 in winter when in high 20s outside in tn ????

Citydude · Dec 4, 2016

M E Cook said:
do you think a propane furnace 40000 btu will heat my shop 24x36x12 ceilings insulated with 3 1/2 rigid in walls r30 blown in ceiling need to get to 60 -65 in winter when in high 20s outside in tn ????

This may give you an idea.

BTU Calculator

ovrszd · Dec 4, 2016

I use a 65K BTU propane furnace in my 42x50x12 shop. I have 12" insulation in the ceiling, 4" in the walls. My furnace plays with the task. I also burn wood when I'm energetic. Let the propane furnace take care of it when I'm not. Whatever you set the thermostat to, it'll keep the temp there, regardless of weather.

If you have a problem you could always add more to the ceiling. That's where 90% of your heat goes anyway.

One last thing, drafts are your worst enemy. If your building isn't tight, start finding the leaks and fix them.

Good luck with whatever you choose. Post your decision and the results with pics of course!!!

George2615 · Dec 4, 2016

According to CD's provided BTU calculator you'll need about 60,000 BTU to heat to 65 deg.
I have 2 garage areas connected by a 12' x 7' opening.
Front garage is 24 x 24 x 14 and has 3 1/2" insul. in walls covered by 1/2" sheetrock. Ceiling has no insul. just a black tarp stapled to bottom of rafters. When I get a-round-tuit I'll insulate my rafters and add some sheathing to help stop the upper heat loss.
Back of garage (shop area) is 18 x 32 x 10 and has 6" rolled insul. in walls and ceiling plus is covered by 17/32" sheathing.
In the back shop area is an 80,000 BTU oil fired mobile home furnace. I can easily heat that area to 60-65. The front stays cooler at about 50-55 with this set up due to poor insul. plus door being opened to get different vehicles in or out. If I set a box fan on the floor blowing heat from back to front I can maintain the 2 areas withing 5 deg. of each other. It stays warm enough for me. If I need more heat in the front I have a 135K BTU salamander with built in T stat.
It was 30 deg. outside this morning and I worked in the garage all day in a T-shirt with the furnace stat set at 65. Don't go too small on a furnace. Better to have a bigger furnace that doesn't have to run very long to heat things up. I keep my back garage at 45 deg. when I'm not out there. I got my furnace used from a furnace service guy. Check with a furnace service company. Many people upgrade home furnaces and these companies service and sell the used ones to guys like me that want some heat in the garage.

ovrszd · Dec 4, 2016

For an idea of what's going on in a person's shop, get one of those battery powered heat laser gadgets. Pull the trigger and point the red laser at whatever you want to diagnose for heat.

In George's case it would have been interesting today to go outside and point it at his roof in the section not insulated. I think it would be an awakening.

George2615 · Dec 4, 2016

ovrszd said:
For an idea of what's going on in a person's shop, get one of those battery powered heat laser gadgets. Pull the trigger and point the red laser at whatever you want to diagnose for heat.

In George's case it would have been interesting today to go outside and point it at his roof in the section not insulated. I think it would be an awakening.

I know I'm losing a lot of heat in the front garage area. Now that I've retired I'm trying to find time to get it done.

ovrszd · Dec 4, 2016

George2615 said:
I know I'm losing a lot of heat in the front garage area. Now that I've retired I'm trying to find time to get it done.

I totally understand that George!!! Being retired also, I have no spare time!!!! Life is good.

George2615 · Dec 4, 2016

ovrszd said:
I totally understand that George!!! Being retired also, I have no spare time!!!! Life is good.

My retired friends warned me before I retired that I wouldn't have enough time in a day to get things done. I laughed and said I'd have nothing but time. Little did I know they were right.

ovrszd · Dec 4, 2016

George2615 said:
My retired friends warned me before I retired that I wouldn't have enough time in a day to get things done. I laughed and said I'd have nothing but time. Little did I know they were right.

Congrats on your retirement George!!!

If you insulate your shop start a thread and post pics. We'll all be glad to tell you "what we would have done".....

George2615 · Dec 4, 2016

ovrszd said:
Congrats on your retirement George!!!

If you insulate your shop start a thread and post pics. We'll all be glad to tell you "what we would have done".....

It will be 8 months the end of the month since I retired. I now wonder how I had time to work for someone else 8 1/2 hours a day.
When I do it I'll add 6" rolled insul. in the rafters and maybe blow in more on top of that then install 17/32" sheathing to the rafter bottom like I did the back. Going to trash the sheet rock walls and replace with sheathing also. I use the garage daily working on cars, trucks, tractors etc.

Deere Dude · Dec 4, 2016

M E Cook said:
do you think a propane furnace 40000 btu will heat my shop 24x36x12 ceilings insulated with 3 1/2 rigid in walls r30 blown in ceiling need to get to 60 -65 in winter when in high 20s outside in tn ????

I live in SE TN also and I am from WI a few years ago. I heat my 24x30?x8 garage with 3.5 insulated and rocked walls and sheetrocked ceiling with I assume fiberglass in the ceiling. Never been up there as there is no opening.

I heat that with a small woodburner in the end and it heats it up comfortably in no time. If I was to get a heater that 40,000 BTU is the exact one i would get.

If you want it to heat up in 5 minutes it may be to small, but if you are patient I am sure it will work.

Norm W · Dec 4, 2016

The second thing you learn, after you retire and you learn that you don't have enough time, is you have no place to go to rest up.

dadster4 · Dec 4, 2016

Concrete floor? Tightly sealed doors? If tight, 40K will be OK 90% of the time once the floor warms up. 40K will maintain a comfortable temp once your shop is warmed up, but don't expect to start from a 25 degree shop and warm it up in a couple hours.

M E Cook · Dec 4, 2016

dadster4 said:
Concrete floor? Tightly sealed doors? If tight, 40K will be OK 90% of the time once the floor warms up. 40K will maintain a comfortable temp once your shop is warmed up, but don't expect to start from a 25 degree shop and warm it up in a couple hours.

going to try thr 40000 just want to be comfortable when working in winter months will let you know

thepumpguysc · Dec 5, 2016

The wife came home w/ a couple of radiant heaters from Wally world the other day. 2 setting, 5100btu w/ fan for 20.00 a piece.
Might be just what you need to "spot heat" your area till the big one takes control.. it'll keep your feet warm while standing at the work bench anyway.. and pretty inexpensive.
Comfort Zone is the name brand.

lostcreekranch · Dec 5, 2016

This one?

http://www.walmart.com/ip/Comfort-Zone-Howard-Berger-Co-Electric-Portable-Heater-Fan-CZ40/19524986

thepumpguysc · Dec 5, 2016

Its the CZ "5".. 5120btu.. site says 24.88 w/ free shipping on a 50.00 + order..
They must have had them on sale cuz I saw the receipt.. 22.00 after tax's.

newbury · Dec 5, 2016

M E Cook said:
do you think a propane furnace 40000 btu will heat my shop 24x36x12 ceilings insulated with 3 1/2 rigid in walls r30 blown in ceiling need to get to 60 -65 in winter when in high 20s outside in tn ????

You don't say where in SE TN, but I'm in NE Mississippi. I've got about 5,500 sq feet of "workshops" with concrete floors.

Leaky as a sieve, very little insulation but they do get pretty much full sun.
My largest "workshop" is 60x40x12 with only 1 inch of insulation in the ceiling to prevent condensation. The winter of 2014-2015 was cold and we actually had snow. But even then about the coolest it got inside the shops was only slightly below freezing. The mass of concrete floor really helps.

But it was cold enough I laid out $140 for a Dyna-Glo Delux 80K BTU Kerosene Forced Air Heater last year and ran it occasionally in the big workshop. It would warm up the big workshop from the the low 40's to 60's in about 20 minutes.

Now I was raised in Northern Vermont and find "working" at 50 to 55 fine as long as I'm moving about and have a decent wool shirt on. And during the winter the house temp is set from 58 to 62. So you might need everything warmer.

But I'm sure that 40K furnace will get you to 60 degrees from the high 20's outside.

lostcreekranch · Dec 5, 2016

Then, must be this one?

http://www.walmart.com/ip/Comfort-Zone-5-120-BTU-Electric-Radiant-Heater-Gray-CZ530WM/21899615

I think I'm going to grab a couple of the first one I sent link on, with fan.

We supposed to be near freezing here Friday morning so will get to test them.

skyhook · Dec 5, 2016

If it were my shop, I definitely would go " wood stove with a blower ", start er up 1/2 hr before you go in and your set. You can't beat the heat these things give off.