Opinions of premade wood floor buildings

[Bill Jobe]

I friend took me to talk to a guy who knows a lot about building sheds/workshops. He said I could pour a slab and build it myself with another guy or 2.
But he encouraged me to consider a 12x prebuilt and delivered. A told him my concerns about a wooden floor perhaps not being solid enough....that I thought in time I'd regret not pouring a slab. He told me if it didn't feel solid enough all I'd have to do is add a second 3/4" plywood floor over the original.
These are the buildings made by Amish. 12 wide is as wide as they build them due to the obvious problems delivering wider ones.
The guy I talked to told my freind later that for $200 he'd come out and pour 42" deep small diameter concrete rods then pour larger slabs on top of those, making 3 pads for each of the 3 4x6 beams they build them on, making certain all 9 slabs were level with the others. This sounded like a pretty good idea to me, but I'm having a hard time with not pouring a slab, but concrete is expensive and there is a 4 cubic yard minimum. The city wants it to be 7" deep if poured without a foundation.

I'm writing to ask of those with a wood floor if they are happy with their choice. I'd also like to hear from those who went with a slab what their opinions are of wood floors.
I was not really wanting to consider one until the guy offers to pour and level pads.

[Bob Bouis]

The wood floor CAN be plenty sturdy, it just depends on how it's constructed. You need to know the joist size and spacing.

[Jerry Bruette]

Are buildings made with treated stringers and ply? I would think that a second layer of ply would make the floor plenty strong and it would be much kinder to your feet and legs.

[Mike Wilkins]

One of the prior Fine Woodworking Shops annual issue had an article on just what you are considering. Not sure what issue; I am at work and cannot check for you, but the author worked with the builder to have the floor beefed up with the intent of placing heavy machines on it. Let them know what your intentions are and they should be able to work with you.

[Jim Andrew]

I would want my shop building sitting on a slab. Even if it is built with a wood floor. If I were building a stick built building, would want a foundation. Not just sitting on dirt.

[Bill Jobe]

I would want my shop building sitting on a slab. Even if it is built with a wood floor. If I were building a stick built building, would want a foundation. Not just sitting on dirt.

That's the only reason I'm considering a wood floor....the 9 concrete pads.
The same guy told us his son bought a 12 x 24 for a little over 4k. I intend to have them build it with 8' walls, if I go that route. That makes for a lot of storage space. I have few machines, just mainly the lathe and a cot for when I get locked out of the house. I'm pretty sure I could get by with a much shorter shop than 24'.

[Ted Reischl]

Kinda went through the same thing here a couple of years ago. But, around here, they can build up to 14' wide, you might want to check on that. If you get with the right guy selling them, you should find out that they will set the floor joist spacing closer if you want. That is what gives the floor strength. They make a version here for guys who want to work on cars, I think they set the spacing at 12 inches.

At any rate, they are certainly a viable alternative. I did not go that route because the better half wanted shop space and she runs a couple of kilns and she needed all sorts of attic space. So we built a 28 X 28 building with a walk up attic. Cost WAY more than a couple of storage sheds, but not all that bad. If memory serves me right, it came in at about 22K all done. Concrete floor, 7 windows, one double door, one single door, attic floored...in other words, ready to go except for insulation. That price included wiring with a new subpanel. The only way you will get a price like that is to be your own general contractor. Other guys who do it for a living wanted upwards of 35K for the building. They have to make a living too.

[Bill Jobe]

Thanks for the info, Ted. 14' would be nice. Wouldn't feel quite so penned in. I stood inside of some made by another builder that displays them in town. One thing's for sure...I wouldn't go any lower than 8' walls. A couple of theirs were and at 6' my head was against the loft joists.

[Nick Reid]

Where I live does them 24' wide and up to 40' long. My step-father has the same 24'x24' building I'm getting; they use 12" on center floor joists that are set on top of 4"x4" pressure treated boards running the opposite way as a bit of a buffer between the ground, even though they put the buildings on #67 crushed stone. They use 5/8" plywood for flooring, and he's been using his as an automotive shop for a few years with zero issues. Would I rather do a slab floor and build a building? Maybe, but this route is cheaper for me ($4,500 alone for a slab vs $11k for the completed building with 2 overhead doors, 1 man door and 3 windows), and doesn't raise my taxes.

I'm a bit surprised the place doesn't offer any larger buildings, this guy just brings them in as two 12'x halves and attaches them together on site.

[Nike Nihiser]

I personally wouldn't have less than a 9 ft ceiling, at 8ft you'll constantly be banging into it if you work with lumber, especially plywood, that long.

[Todd Mason-Darnell]

I went with a slab for a couple of reasons.

First, we are on a soil with a very high clay content, so as a result, it moves--a lot, a whole lot. Any wood floor buildings, even ones on a concrete pads like you describe, end up being wonky after the first summer (my neighbor sank his post 30 ft in and still had issues).

Second, I live in the "sub rural" zone, so any crawl spaces or even small gaps under buildings become critter and snake havens.

I ended up having a team pour a 16 x 24 slab of 5000 psi concrete and never looked back.

[Bob Bouis]

Is a slab really better for clay soils? If your conventional foundation moves, you can get out there with jacks and straighten it up yourself, easily. If your slab moves, you've got to call in the big (price) boys.