# How deep of concrete slab under a pole barn?



## SkizzlePig

We're looking to build an equipment shed with a concrete slab floor. It'll be the home for our 60hp tractor (5000lbs+/-) and the implements. It'll also be the sometimes home for ATVs and such.

How deep of concrete will we need to pour to not get cracks? I was thinking 6", but I really have no clue.

Thanks in advance!


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## unregistered168043

Mine is 6 inches, its 7 years old now and no problems.


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## RonM

If you discover concrete that wont crack get in touch with me......we will get rich.....it all cracksto some extent, but to answer your question my floor is 4 in on a good base.....5 in should be plenty, get 3500 mix....


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## ihuntgsps

It depends on your soil, climate, etc.
If you have good draining, well compacted soil, you can get away with 4" and be fine.

use the plate compactor on your level builidng site then levelinside your concrete forms with washed fill sand then use a vibratory plate compactor and pack the base every couple inches until it is stable.

I almost always use 2x6 form materials and pour my floors 4.5 to 5" thick.
Use plenty of rebar to stabalize the slab. 3/8" or 1/2" will be fine.

a good 3500 lb mix will serve you well. No need for the 4000 or 5000 lb mixes in your application. I would advise against use fo fiber in your concrete becuase it doesnt finish as well.

Edge it and finish then make sure you cut in multiple runs at least 3/4" deep on a 4" slab. Should last very well and have minimal cracks after several years.


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## farminghandyman

a lot depends on how your prepare your base, if you have solid and well prepared base, 6" should do it,

I like the use of fiber (NO IT DOES NOT REPLACE RE-BAR), but it does help and work as micro re-bar, yes your floor may have hairs for awhile, but one can power trowel it to a very smooth surface, a lot of it just depends on how long one wants to work on it, my knees can't take much hand troweling any more.

try to not have cold joints, in other words try to have the number of trucks to do your pour or section of pour all at one time, if you have a significant time lag between pours on the same slab section you may get a crack at that point,

but like said your concrete will crack, that is what control joints are for, to allow it to crack where you want it to or where it not ugly, usually about every 10 foot is what I have experienced, if no control joints are used,


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## TNHermit

Put down a good 6-8" stone 00 then 6's. you can put sand over that but i didn't. then 6" concrete. Don't let it have more than a 4" slump. I forget the bag mix 3500-4000 i think. i have a 30x60 with cuts at 10 foot. No cracks in ten years. gotta cut it and its easiest if you cut after a week or so.

See if you can get a front unloader. i made three 20 ft pours since they only hold about 11 yards a truck and mine was only 4 inches for the wood shop.


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## jwal10

4" is thick enough with rebar around the edges and concrete wire mesh. Good compaction. I use 2"x4" forms and leave 5" at entrances, 5" aproaches. Water good before placing concrete. I make cuts every 8' in the slab, slabs the width of bays. I had 5" in my shop and had huge equipment in there. If running a tracked vehicle I put down some old 2" boards....James


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## SkizzlePig

Thanks guys! Using this info I just got a quote for a 24' x 24' x 6" pad delivered and poured onsite.

The quote was $3,000 ... seems high to me. Thoughts?


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## RonM

1 yard of concrete is 80 sq ft @ 4 in thick.........24x24=576 divided by 80 =7.2 yards say 8 yards of concrete figuring your entrance pad...for 6 in thick divide by 54 that makes it 10.6 or 11 yards you will need,how much is it a yard........if it is $200. a yard you have $2200. in material...that leaves $800 for labor.........might not be too bad a price...


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