How to heat my shop?

I have a 45' X 30' X 10' Morton pole barn that I plan on heating this winter. I live in central Illinois. I plan on insulating it well. We live in the middle of town and there is very little wind. Here are some other items to consider:

- My house has natural gas service and I've decided that I want it to "fuel" my shop heat solution. (no electric/wood/lp)

- The shop also doubles as our only garage, so 1/3ish of the building will be used as a place for our 2 vehicles. (I'll post a diagram once I get home tonight to give you a visual).

- Our dog lives here (so I'll need constant heat, I'm not real sure but I think 55ish would be more than enough when the humans are not there).

- No need to have quick heat when I go out to work (the speed to get an additional 5 to 10 degrees higher than the "dog" temperature is not important/radiant is OK).

- I'm cheap.

My current thought is to get a radiant tube heater (natural gas) and position it near the workspace end of the shop. The SUV/Truck space doesn't need to be "hot" because we'll likely be in that space for short periods of time, and as long as they vehicles can thaw overnight when the snow gets heavy, that will be enough heat for me.

My outstanding questions are:

How big of a heater do I need? I've looked at several BTU calculators and they vary wildly based on the inputs (low temp factor being the largest input variant).

If I position a radiant heater on one half of the building how well will the heat transfer to the other half? I don't have a lot of experience with radiant heaters. I know positioning is key so any suggestions on where and at what angle/direction would be appreciated!

Is radiant tube/natural gas the right solution?

Thanks! (I'll post the diagram tonight)

 

I recommend downloading and paying for HVAC-Calc. I just did that to figure out the heat loss for my house. It's 49$ for two months of functionality. You can play around with with different scenarios all you want. You can enter the lowest outside design temp and then the inside design temp. Well worth it. They let you download it as a trial as well. It just won't give you all the heat loss info.

 

Here is a diagram of the layout:

After some more research I may be leaning towards 2 Mr. Heater 40K heaters: MH40NG.

Additional question: What is the best way to position 2 of these guys?

Thanks for the info drooplug. Since I'm foaming the entire shop and these heaters all have square footage estimates I think I've decided that I have enough info on heat loss/BTU to make a decision.

 

Hi dayton, not an expert on placement, but looking at your drawing i would place a single heater at the top of the drawing where it is labeled "45" and point it across to the workbench. Whether you need a second unit or not would depend upon the insulation you add and the garage doors. Tough to get well insulated and well sealed units. Also tough to add more heat capacity just to heat all outdoors.

Tell us what you plan for insulation, windows, attic space, and stairs.

Bud

 

My house is about 1600 sq ft. It's old and the 2nd floor is not very well insulated. The first floor is pretty good, but no where near sprayed in foam. The heat loss for my house is are 70,000 BTU. That's on a 10 degree day with me trying to maintain 72 degrees inside. Those two heaters would provide enough heat for my house.

Your shop is going to be very well insulated and you have no intention of keeping it as warm as 72. I don't think you need 80,000 BTU's of heat.

 

I'm going to have 3.5 inches of open cell (.5 lb) foam sprayed throughout. I have 3 insulated garage doors (guy before me was a car buff so there is an additional door in the top right corner). I plan on hanging OSB on the walls. There are four windows (2 on each 45' side). 1 walkthrough door in the top left corner.

If 80K is overkill, what's a good size?

 

I don't know. I just wanted to make the point that just because the box says it's good for so many square feet doesn't mean it is right for you. That's why I reocmmended using that software. It's only 50$ for 2 months and would probably save you more than that in the long run.