Building an interior space inside a pole barn

[Asha'man]

I have a 40x60x12 post-frame shop building (link in sig) that I use for working on cars, storage, and basically all the usual shop stuff. However, it's well-ventilated (ridge vent, eave vents) and only has foil bubble insulation inside, and the sheer size of it means that effectively heating the space is nigh impossible. I'm thinking of building out an interior space inside that I can heat with ease, keep tools, maybe have an office space or workout area, and have enough room to work on one vehicle at a time. Ideally there'd be space on top for storage, though I'd have to tiptoe through my trusses to some degree. I'm picturing doing a 20x30 or 20x40, basically taking up two bays of length and either a partial width or full width across the existing building. If I butted it up against the wall with the eavelight, I could use clear panels and retain the natural lighting on that side. Those are ten-foot bays, so picture coming off the back wall 20 feet, and then spanning the width of the shop probably 30 feet or so, leaving a space in the corner by the Ford banner.

What's the general opinion on something like this? I've seen it done before, but I have no idea if it ends up being cost effective. Maybe it would make more sense to pick up a couple of rad tube heaters or a waste oil furnace and just try to keep the whole space moderately comfortable when I'm doing stuff out there, rather than having a smaller space that's more conditionable all the time.

Opinions? Examples? Pictures?

 

[Jeff Ivers]

I have a building within a building that I installed in my barn. However, it is only 10 x 12 and only carries relatively light load of the ceiling structure and scrap lumber stored on top. For the size you are talking about, you will have to span a much larger width and be able to support far more weight - what is the depth of your slab? If you do determine it is feasible and proceed, I would build out from the right rear corner in the picture where the car is parked. Use the left rear corner for storage and add some windows to the built out area that face the clear panels to take advantage of the light.

 

[rburke65]

Cost effective is different for very one. Cheaper to heat less square footage obviously. Ya need to figure YOUR cost of energy, your cost of a heat source....boiler, furnace, etc....then maybe duct work. Cost of getting a gas line run or electric. Can you do all this your self? Insulation. Where ya getting th waste oil ..... Waste oil heater....Have to get out your pencil. Good luck.

 

[Asha'man]

Thanks for the input. Slab is 4" nominal, nothing crazy. I'll be doing the work myself so there is that. I have an old woodstove that we've had knocking around for years that would heat a smaller space with ease, and I can just picture a gloriously warm space in the shop when it's frigid outside.

 

[G-ManBart]

What you're talking about is essentially what I did with my build. I built a wall that followed one of the trusses and connected the two. I pretty much just screwed the wall top plate into the bottom of the truss. I drilled holes and used coated deck screws, so it's not going anywhere.

Insulating the exterior walls could be more of a pain unless you're planning on using spray foam. I knew I was going to be using steel liner panel on the inside, so I built a framework for the liner panels, and was able to hang roll insulation off of that. I went one step further and added 1.5" foam in between the purlins since it was otherwise wasted space.

The biggest thing for heating/cooling will be insulating the ceiling. Are you thinking of covering the trusses with a ceiling, or leaving them open, and then adding insulation on the inside of the roof panels?

 

[matt_i]

Seems good, I'd use a flat joisted ceiling that you can walk on/store things on as a mezz, keep the side-light open/below the top level. Sort of like a flat/bridge truss or I-joists. Ideally around 18" of space for insulation which I think I'd put in as cellulose loose fill. Stick framed sidewalls 2x6. Then go with heat source. Wood is free if you have the right source but needs tampering to cut and split, light and cleanout, sweep chimney, etc and some ramp-up to get the fire cooking. My grandfather had wood heat in his shop but it seemed like ~2hrs to get everything warm. With gas fired heat I can have my shop nice and warm in 5-10 minutes depending on how hot I choose to make it.

 

[bowhuntr311]

I would think you could pretty easily stick frame up your walls (2x6 24"oc). Attach to the exterior walls and to the floor with some concrete screws; not many screws the wall wont need much to hold it in place. Put some kind of I-joist for a ceiling to span your width. Put everything flush to the rafters and tie into your existing walls. Should be plenty solid structurally. Then some batt insulation in rolls. Fill your ceiling with a couple layers of it. Doesnt address your natural light issue though; Menards sells some "garage/utility" windows pretty cheap in common sizes. 3 in 20ft on the wall towards the natural light could let some in.

Heating something like 20x20 with an old barrel wood stove....hahaha....your gonna cook yourself out of there in about 10min flat. I had a barrel stove in the corner of a 24x20 uninsulated attached garage in northern MN. Outside temp was -10, inside temp was about 25. I would fire the stove up with some dry hot burning wood like pine; I always placed a fan behind the stove moving air around. With in 10 min it was sweatshirt temp, with in 20 it was HOT. If I kept a fire going from 6-10pm and then would shut the stove down to put the fire out and go to bed. Next morning the garage would still be above 32.

 

[Asha'man]

G-ManBart, do you have any pics of your setup? Sounds very similar to what I have in my head.

I heat the house with wood as often as I can, so I have a decent woodpile and am usually scrounging more. That's why I'm leaning toward wood heat, though I'll need to make sure it's not a waste in the giant space and that my insurance will cover the building with a stove in it (!).

The posts would be a great basis to attach walls to. My trusses should be rated to hold the weight of drywall (at least I ordered them so), but not more than that and I don't intend to attach any part of the interior space to them. It's 12' and a couple inches to the truss bottoms, so I'm kinda picturing the mezzanine storage area being around 11' or so. Given a straight/flat joist setup for that roof, that would put my interior ceiling height at 9'6" or 10', which seems like plenty. I'd basically have a couple of 10' wide bays on the mezzanine, between the trusses, and I'd just have to be careful not to load the trusses with **** up there. Shouldn't be too hard.

I had a buddy who had a 30x40ish shop with a small work area (15x20?) built out inside, but the work area had an open front to the rest of the shop. He said a double 55gal barrel stove in the back of the work area kept that space at t-shirt levels and the rest of the shop at hoodie levels even when it was legitimately cold outside. I'd like to enclose the interior space a little more, but maybe a sliding door or rollup door would be slick. Keep it open most of the time, be able to open it to get vehicles in and out and if it got blazing hot inside, but able to close it off to retain heat.

 

[lakeroadster]

A fellow Coloradoan.

Take a look at my build thread (see signature line below). I'm in the process of building what I call a maintenance space in my pole barn.

On a pole barn, by design, the slab moves independent of the columns. You need to ensure that it can continue to do so as you move forward with internal structures.

You'll want to leave room for the slab to move, and the trusses to sag, etc. That means don't build the wall tight up against the truss bottom, and don't physically attach the wall to the slab and the support columns.

It's not a big deal if you plan ahead, and design accordingly.

Again, I've got details of that in my build thread... check out post 258..... http://www.garagejournal.com/forum/showthread.php?t=289293&page=13

Do you know the lower chord rating of your trusses? if you can get that information you may be able to utilize a loft for additional storage. We did that, more data starts at post #234.... http://www.garagejournal.com/forum/showthread.php?t=289293&page=12

Good luck to ya... if you have any questions feel free to ask.

 

[G-ManBart]

G-ManBart, do you have any pics of your setup? Sounds very similar to what I have in my head.

Tons of pictures in my Photobucket album....sort of follows how the build went in stages. There's a video near the end where I do a walk around of the inside, and I have another video of the barn side that I need to upload (forgot).

Let me know if you want pics of anything specific...good chance I have them, or can take them.

http://s454.photobucket.com/user/G-ManBart/library/Barn?sort=3&page=1