Heating Options - 42x40x14 plus loft (40x11x7)

[Homer14]

Hello,

I'm putting this thread here in case people are willing to provide some input and opinions while I continue to research the forum and the internet. I've probably read about 100 threads various places thus far and I am taking notes.

I've got a 42x40x14 pole barn up. There's stairs in the corner to a 42x11x7 loft. I'll be doing fiberglass R19 I believe with the vapor barrier and then osb for walls. The ceiling will likely be white steel/sheet metal with sprayed fiberglass as well (R30?). I'll insulate the walls of the loft as well with whatever is appropriate. [EDIT] There's already a cement floor in place. Vinyl sided and Shingle Roof.

I'm in Michigan. We hit 0 degrees F occasionally and tend to float around the teens in the winter. In the summer we may hit 90-100 now and then and float around the 90's.

What I'm trying to figure out? I'd like to heat everything [EDIT] and have Natural Gas ready. I'd at least like to heat/cool the loft which will become a small nicely finished man cave. I dont mind cooling everything but I'm open to just cooling the loft area when desired while heating everything. [EDIT] I am open to keeping a lower temp while not in use then cranking it up before I use it for a couple hours each night now and then or just maintaining a temp. Once in a while a 10' door will be opened to move a tractor in and out for plowing and someday down the road to move cars in and out to work on a lift with.

What do I go with? Radiant Tube, Heat Pump, Standing Furnace, Hanging Furnace, Infrared, Used Oil burner, etc? Do I heat the bottom with something, such as a hanging furnace, and then do something different on the top such as a heat pump? How do I calculate BTU for the lower and upper in various situations such as a closed door on upper while heating lower?

I plan to work in here on nights and weekends and have occasional sausage fests with buddies in the loft when its done for sporting events or fights with the wife.

Side note: I did get a free 75k btu standing furnace from a friend. It seems undersized but it was free so if it makes sense to use it then I'm ok with that but I'm also ok giving it back and getting something else.

This is a brand new project, I have options and I'm open to all of them. Please share opinions.. I'll follow-up as I update my notes and read from others.

Thanks!

 

[D45]

What fueling options do you have........NG or propane?

Will the barn be heated all the time (just turned down) or will you only heat it when you are out there?

I bet that 75K would work, especially if the temp is maintained in the barn and it is insulated well

 

[Homer14]

What fueling options do you have........NG or propane?

Will the barn be heated all the time (just turned down) or will you only heat it when you are out there?

I bet that 75K would work, especially if the temp is maintained in the barn and it is insulated well

That was a fast reply thanks. I edited my main post. I have natural gas ready at the barn. I am open to maintaining heat if needed (e.g. furnaces arent meant to hold 40deg) or keeping it cooler unless it's time to work.

when you say maintained with the 75k free furnace I got, what was in your mind as far as maintaining temp wise? I'm not an expert but I read maintaining a low temp on a standing furnace to condensation issues and heat exchanger issues?

 

[Homer14]

I'll edit this as I find more examples of other peoples dimensions and btus. These are from other peoples posts and what they went with for reference:

[Forced Air Hanging Furnaces]
- 32x48x10 75k btu (15,360)
- 34x34x14 75k btu (16,184)
- 40x52x10 125k btu (20,800)
- 42x40x14 N/A Me (23,520)
- 36x48x14 100k btu (24,192)
- 44x48x14 150k btu (29,568)
- 40x60x14 100k btu (33,600)
- 32x75x16 75k btu (38,400)
- 40x60x16 75k btu (38,400)

- 40x50x16 + 20x50x16 150k btu (48,000)


[Infrared Radiant Tube Heaters]
- 28x28x8 75k btu (6,272)
- 30x38x12 80k btu (13,680)
- 32x40x13 75k btu (16,640)
- 40x52x10 80k btu (20,800)
- 44x40x12 125k btu (21,120)
- 40x60x12 2x 60k btu (28,800)

 

[D45]

Hanging wont take up any valuable floor space, which I like

NG is the best route, for sure.......cheap to heat

It is a no brainer use NG for the heat then

I have a 75k in my somewhat poorly insulated 1,000 sq ft garage.......NG. It is not heated 24/7 during the winter. I usually turn it on for an hour in the morning and an hour at night.......it heats the area up well and pretty fast.

Is your current 75K a hanging style or a residential style setup? Both will need to be properly vented to prevent moisture and condensation issues in the barn

 

[D45]

How many windows do you have?

How many doors? What size? Insulated?

 

[Homer14]

Hanging wont take up any valuable floor space, which I like

NG is the best route, for sure.......cheap to heat

It is a no brainer use NG for the heat then

I have a 75k in my somewhat poorly insulated 1,000 sq ft garage.......NG. It is not heated 24/7 during the winter. I usually turn it on for an hour in the morning and an hour at night.......it heats the area up well and pretty fast.

Is your current 75K a hanging style or a residential style setup? Both will need to be properly vented to prevent moisture and condensation issues in the barn

The 75k free one i have is a non hanging floor model. I've read using a non hanging style one will run into condensation issues in general if the barn were kept low temps like 40-50 which they really aren't designed for, versus a hanging one.

 

[Homer14]

How many windows do you have?

How many doors? What size? Insulated?

upper 42x11 loft has two 4x4 windows (one a at each end)

lower 42x40 has 4 3x3 windows, 1 8x7 insulated garage door, 2 10x10 insulated garage doors, and one standard 3' insulated service door.

 

[Showkey]

The 75k free one i have is a non hanging floor model. I've read using a non hanging style one will run into condensation issues in general if the barn were kept low temps like 40-50 which they really aren't designed for, versus a hanging one.

Hanging vs floor has little effect on the condensation or internal rust issues. Most if not all garage type hanging furnaces warn not to use continuously at temperatures lower than 50*.

 

[D45]

Most if not all garage type hanging furnaces warn not to use continuously at temperatures lower than 50*.

Why though..........condensation?

If so, just run it longer to burn it off?

 

[Showkey]

Why though..........condensation?

If so, just run it longer to burn it off?

Don’t think that works.........
Here is what the install instructions say:

 

[bobbyjean]

you can hang the free unit you have horizontally...add some ductwork and that should be close for downstairs....if you can airseal the **** out of the place...every nook...it all helps...get yourself the "pro" gun for foam cans on amazon for 15 bucks and have at it.
for upstairs you could go with a ductless 1 ton(12k) ,or depending on your layout a small furnace with a-coil...now you need two chimney's..going hi efficiency will give you pvc exhaust ....if you have access to free oil then of course waste oil...but not sure your insurer will cover that.

 

[Krzewinskibe]

I put 150K heater in my 44x48x14 garage. I have 3 large garage doors that do have some leakage at the edges. Heats from 40 to 60 pretty quickly.

Hanging vs floor has little effect on the condensation or internal rust issues. Most if not all garage type hanging furnaces warn not to use continuously at temperatures lower than 50*.

My Modine 150K heater has no such warning. It says "Heaters are designed for use in heating applications with ambient startup temperatures between -40°F and 90°F and ambient operating temperatures between 40°F and 90°F."

Implies continuous use at 40+°F

 

[D45]

^^^^^^this

I just read through my manual, twice

There are no low temp use warnings on my Modine Hot Dawg 75K (power vented)

 

[Showkey]

^^^^^^this

I just read through my manual, twice

There are no low temp use warnings on my Modine Hot Dawg 75K (power vented)

Modine tech support response:

Per the installation manual, the HD units are designed to operate in ambient temps of 40 to 90 degrees. I would not recommend setting the thermostat below 40 degrees, as it would most likely cause the unit to short cycle which can create condensation in the heat exchanger and premature failure. Please let me know if you have any further questions or need anything else.

Regards,

Which confirms the implications drawn on post 13

 

[Homer14]

Are these modine hd units better designed to sit around 40-50 than a standard house furnace would be?

I'm starting to like the idea of the radiant tube heating and I keep wondering if i could pull something off with that and then somehow heat/cool (or only cool if needed) my loft area with something else? Any thoughts going that route or does the free 75k btu house furnace change the game a bit?

My mind is going all over the place with options haha. This is why i posted and continue to research.

 

[Showkey]

Standard 96% 60-80k an be purchased for $800-$850 delivered. Easy install Venting with PVC and you gain over 20% efficiency over a standard garage heater.

The down side if there is one .......they are condensing so the you have to have a way to drain the water. They can not be shut down in freezing conditions. Big temperature swings in the garage are not a good thing and 40-55 temps are better storage temps especially of collector cars. The higher temps the better with the down side being the cost of fuel. 20% efficiency gain can can be a huge off set on those fuel costs.

My next garage heater will be a 96% furnace. Mounted horizontal off the ceiling.

Example of furnaces with pricing.....
https://www.alpinehomeair.com/viewcategory.cfm?categoryID=128

 

[Homer14]

so im now leaning back to forced air.

main reasons?
- ill have good insulation
- i need a/c at some point, can add right to furnace easily/quickly
- time to heat
- cold/hot spots
- possibly painting and finish work on things (avoiding infrared to the objects)

Now i need to decide on the btu's and hanging vs floor model (id put it up on a shelf in a corner). Is the 75k free one enough or do i buy a larger one (100-125k btu)?

Any comments on ducting? A friend suggests spiral for the look mainly.

 

[finn]

I’ve been heating my 32x75x16’ with a 75k hanging heater, and I’m 500 miles north of you.

Main advantage of the ducted residential furnace would be that it’s quieter, has better filtration, is ac compatible, and there’s probably less air blast for good heat distribution.

It will cost more to install, though.

 

[zmotorsports]

As others have stated, NG is going to be your best bet which is sounds like you are prepped for.

I like just a plain hanging gas-fired forced air heater for heating my shops. I had a 75k btu Modine Hot Dawg in my last shop which was 34x34x14 and it did a great job.

In my new shop that is 40x50x16 (with attached 20x50x16 storage/RV bay) I installed a Reznor UDAP 150k btu gas-fired heater. Probably a bit overkill but heats the shop well.

My cousin has a 40x60x16 and he uses a Reznor 75k btu to heat it which is also does a good job but seems to run a bit longer than mine.

 

[finn]

As others have stated, NG is going to be your best bet which is sounds like you are prepped for.

I like just a plain hanging gas-fired forced air heater for heating my shops. I had a 75k btu Modine Hot Dawg in my last shop which was 34x34x14 and it did a great job.

In my new shop that is 40x50x16 (with attached 20x50x16 storage/RV bay) I installed a Reznor UDAP 150k btu gas-fired heater. Probably a bit overkill but heats the shop well.

My cousin has a 40x60x16 and he uses a Reznor 75k btu to heat it which is also does a good job but seems to run a bit longer than mine.

Running longer can be a good thing.

 

[Homer14]

Forced Air it is.

Are there A/C options for the hanging types? I suppose it just makes sense to mount a standing furnace up on a corner shelf and later add the A/C to it.

I've updated the examples above of sizes and btu's of hanging furnaces. It seems 75k would do it based on those real world examples and maybe 100k is more ideal. Just two of those examples are using 75k btu for a much larger area while others closer to my area jump to 100k or so. I'm beginning to feel more comfortable with the 75k now but I'm not sold. This forum is helping a lot..

 

[zmotorsports]

Running longer can be a good thing.

I agree, but within reason. You don't want short cycling but I don't want it running 30 minutes at a time either. That tells me it's struggling too much.

 

[Homer14]

oh the joy of options... if i considered only a/c on upper... any thoughts about this?

1. tube heating on lower level (couple tubes probably hung at 13' ish)

2. a small little furnace/ac on upper level hidden in the trusses somewhere

this would not give me a/c on lower but maybe i dont need it as much as i think i do (future hobbies with wood, motors, toys, cars, etc). does anyone out there heat a lower and only heat/cool another section (such as my upper) separately?

 

[Homer14]

Current state and plan. Thanks for all of the input. this board is excellent for knowledge and support.

I'm going to:

1. install tube heating lower level (ill have to figure out what sizes, maybe 2 tubes 13' up)

2. see if i can sort of convert the free standup furnace to a directional blower with short ducting, similar to a hanging furnace for if and when i want a quicker heat up. i suspect ill rarely use this.

3. do a mini furnace+ac or a heat pump for the loft area only. ill have to figure out the size for that too. im wondering if i could hide it in the trusses since it will be so little.