Wed Nov 16, 2011 9:52 pm

I plan to start soon on a shop/shed 20x40. I'm thinking a slab 4 inches thick should work well for cubs. Any thoughts on the minimum thickness of slab and about how much is a yard of cement?

Re: shop

Wed Nov 16, 2011 10:01 pm

4 inches of reinforced cement should be adequate for your shop.

On the cement. Only way to know is to inquire at your local concrete shop/firm/plant. My ball park guess is $1300- to $1500- for the cement. But then, the local cement plant has a delivery charge based upon milage and quantity.

Re: shop

Wed Nov 16, 2011 10:02 pm

Four inches should be good. I would dig out a little deeper at the doors/entry ways for added strength. I see you are is St. Marys, the last time I called the company in Baldwin, Fla, they were charging somewhere in the $100/yrd range for fiber.

Eugene is quick!! :D

Re: shop

Wed Nov 16, 2011 10:11 pm

I built a 30 x 50 barn a few years ago. I had planned on 4" only because I had all cub cadets. I decided at the last minute to install 4" of crushed stone and 6" of concrete. I am sure glad I did.i now have a couple cadets, 2 farmall cubs and my grandfathers old H.

Check with your local concrete supplier for cost per yard. I'm sure they have a minimum and a possible delivery charge.

Labor to place and finish should'nt be much more. All depends on location.

Just my .02

Re: shop

Wed Nov 16, 2011 10:48 pm

Thanks guys. That is a good idea of a little deeper at doorways. I had also not given any thought to crushed rock. I'm in a sandy location so will think harder on how to proceed. I may have to get cement from Jax. FL, 30 miles away. No demand for cement here because building has all but stopped around this town.

Re: shop

Wed Nov 16, 2011 11:05 pm

Definitely do a haunch pour, which means that as others have said, the slab is thicker around the edges and at doorways. Stone may not be necessary in your area. I know that we built a power plant down in Naples Fl, last year, and everything was done right on top of compacted sand. They had sand down about 20 feet, then bedrock. Our biggest problem was that water table was only 6-feet down, so the sand could possibly liquify under the vibration of the gensets. So we built on auger-cast piles down to bedrock, for the real loads. Anyway, TOTALLY different beast. As long as you have drainage away from your building, and you can level and compact the sand, it may be fine. Ask around with local construction guys or at the building dept. in town, and they will let you know what you need to do.


Re: shop

Thu Nov 17, 2011 7:58 am

I just had the gravel floor in the back of my shop dug out and poured this spring. The contractor recommended 4" with fiber knowing that I'd be putting my compact tractor on it. Total cost was about $1500 including digging out about 3", compacting what was left, pouring the slab to match the existing in the rest of the shop, and cutting the control joints. They also added the black expansion joint stuff along the edge of the existing slab as a thermal break since there's a wall there and the other side is heated. This was for a 16x30 area.

Re: shop

Thu Nov 17, 2011 8:28 am

Personally I would not dig it out I would build it up. That way in hard rains all the water runs away from the building. All my building at the farm are at least 18" higher than the surrounding grade but then I have a lot of snow and spring runoff to deal with.


Re: shop

Thu Nov 17, 2011 6:54 pm

On my 30x40 I have 8-12" of stone then 5" of the higher PSI cement (I can't recall exactly what it is rated at but I went with the PSI rating for roads). Ended up costing about $500 more for the higher PSI and thickness but I also have no concerns now with breakage. My eqpt. is under 5K but I had a track hoe in there a few weeks ago (9600lbs) and no issues what so ever. Also if you ever add a truck/car lift some require a bit heavier cement base than normal.

Re: shop

Thu Nov 17, 2011 8:14 pm


[20' x 40' x .333'] + [120' x 1' x 1'] = 14.31 cubic yds. the 120' is for footing around the premiter of bldg. At $75.00 / yd = $1073. At $100 = $1431. Just some figures to work with. Of course this does not include the reinforcing wire/steel.

Re: shop

Fri Nov 18, 2011 7:33 pm

regwal wrote:I plan to start soon on a shop/shed 20x40. I'm thinking a slab 4 inches thick should work well for cubs. Any thoughts on the minimum thickness of slab and about how much is a yard of cement?

Are you guy's talking about concrete or bulk cement for mixing on site ?
Cement is mixed with sand and stone to make concrete.
Is this a regional term for concrete by calling it cement?
Kind of like having a ham and cheese sandwich on two pieces of white flour.
Just wondering.


Re: shop

Fri Nov 18, 2011 7:41 pm

Russ, I think he is (read we are!!) using the terms as one in the same, southern talk I guess.
Kinda like calling all carbonated beverages "cokes", they just come in different colors and flavors!! :D

Re: shop

Fri Nov 18, 2011 7:56 pm

Thanks, now I know :)


Re: shop

Fri Nov 18, 2011 7:57 pm

The word cement is used instead of concrete in places other than the South. :D

Re: shop

Sat Nov 19, 2011 9:19 am

Terminology is a wonderful thing! Nobody pours a concrete floor here. Everybody calls them cement floors. Cement contractors pour concrete and we end up with cement floors and sidewalks. But almost everyone calls driveways concrete driveways. Go figure!