Framing on an unlevel pad

[Marshall Johnson]

Last year we had a 16x20 pad poured for my shop. I did not pay close attention. The cement contrator simply followed the slope of the land and did not bother leveling at all. Consequently on the 16' side, the pad is 5" out of level. Not sure what to do.
1-pour a level pad on top
2-Deal with it while framing...
3-Mudjack
4-pour a level 4" apron around the inside edge of the pad
Cost is a concern, or I would just rip it out and start over. I have attached an image of the apron idea.shopIIb.jpg

[Jamie Buxton]

Me, I'm a wood guy, so I'd fix it with wood instead of concrete. Wood is a much nicer material, and I have all the tools to work it. I'd do something like your apron, but I'd make it from wood instead of concrete. I'd put extensions on the foundation bolts that are now sticking up out of the concrete (right?). Then I'd put the mud sill down, hiking it up on blocks so that it is horizontal all around the pad. I'd put blocks right near every foundation bolt, so you can tighten the nuts without distorting anything. As usual, all wood touching the concrete needs to be pressure-treat. After you have a horizontal mud sill, you can proceed with framing, with studs that are all the same length.

[Brian Tymchak]

Wow. If I were in your situation, I would take the opportunity to cap the pad with a new pour. That much slope would nag at me no end as it becomes a factor when setting machines, benches, cabinets, etc. I want all my tool surfaces sitting somewhat close to level as they are easier to use and I feel that it translates to my work in better cuts, etc. My basement floor is sloped to the middle (somewhat by design, somewhat by settling). When I built my bench, the slope in the floor was noticeable to me while working on the top of the bench. So, I shimmed it level.

[Jason Roehl]

I think your "contractor" should rip it out and start over...on his dime. Did he even know what it was for? As a shop floor, that will be incredibly frustrating for virtually everything you do.

[phil harold]

If he did that poor of a job I wonder what else is wrong

If you are stuck with the slab
I would frame a wooden floor over it
The build the walls

[Brian Holcombe]

That would drive me crazy, so I would have it leveled.

[Greg R Bradley]

Use it as a concrete parking area outside a shop built on a proper foundation? It sounds like he doesn't know how to do it properly so how can he do it over and do it right this time?

I would be very concerned about building anything on top of something that must have been done so poorly.

[Jim Andrew]

I really don't believe in using lawyers to solve problems, but in the case you described, I'd reconsider.

[Steve Milito]

I would never consider building on a faulty foundation. It's just wrong in every way.

[Michael N Taylor]

You can simply set a string line from each corner and cut every stud to length to get the top of the wall level but I would go after the contractor to make it right. I hope when you had the work done you had a contract saying that the slab would be __ thick and level pouted on a gravel base __ thick and have a vapor barrier etc. f you did not have anything in writing then you will probably have to deal with it your self but starting out with a bad foundation is never the best thing to do.

[Von Bickley]

I think your "contractor" should rip it out and start over...on his dime. Did he even know what it was for? As a shop floor, that will be incredibly frustrating for virtually everything you do.

I agree with Jason.......

[Ole Anderson]

Is it just a flat slab, or does it have a rat wall or even a full foundation around the perimeter? And, hey Marshall, welcome to the Creek! If you add your location to your profile, we will see where you are located, as that can have some bearing on how the slab should have been constructed and how your shop will be used (heated?). In any case, I agree with most previous comments: bite the bullet and get the slab done right by a reputable flatwork contractor or you forever regret it. But as you said, cost is a concern, just be sure to factor in the additional cost you might incur by having to Rube Goldberg a solution other than starting over. And I see you are putting an overhead or other larger door in as well as a man door. That will take up valuable wall space for benches and tools. I would just opt for single 36" man door unless small tractor access is expected in which case I would consider eliminating the man door. But that is just me, I don't know your potential list of stationary tools.

[Jeff Duncan]

The first rule in construction…….is to start on a good foundation

If your foundation isn't good, your building won't be good.

good luck,
JeffD

[Patrick McCarthy]

Marshall, I think it really depends upon what the cement contractor knew at the time. If he knew (so, you told him, or you had plans and a permit that so specified, etc) it was going to have a building upon it, then it is going to be his fault. If you just said " I want a 16x20 pad and as cheaply as possible" . . . . then you got that for which you asked and nothing more. As a pratical matter, I can't imagine any competent contractor NOT asking the purpose of the pad, the anticipated weight it is going to be supporting, the amount of rebar, the depth of the footings, whether you want a stem wall, the layout of the doors and windows so as to calculate the location of the anchor bolts, whether you wanted an apron interface for a future driveway entrance, etc, etc, etc.

I sense there is a bit more of the factual detail we are missing.

Bottomline, whether it is your nickel or his, it has to be analyzed and evaluated. I would not have that contractor be part of the evaluation process.

My sense it you need to start over rather than putting bandaids and duct tape on it. Money is ALWAYS a concern, but you need to take a longview of it. YOu don't want to spend the next 20 years exclaiming "Gosh, this slab/floor is driving me nuts. I wish I would have just started over and done it right."

JMHO, YMMV

[Ted Calver]

That would be unacceptable to me, but it sounds like you let it ride for a year so you may have no recourse with the contractor. As shown, any water getting into the shop is just going to pool against the down slope wall unless you install through wall drains. My first choice would be to tear it out and have it done right by someone else. Second choice would be to pour a level pad on top.