Concrete Floor

[leversole]

Looking to build a pole barn for my truck...is a 4" 3500 PSI slab adequate?

Thanks

[mowerman]

dont know,,,but i heard those portable cement truck guys,,,give you allot better price,,than the mixer outfits,,hope that helps you.lol.bob

[Olivetroad]

I poured my shop floor 8 inches thick which was overkill, but the four inch thick apron we poured on one end has cracked in several places and I bet I replace it in a few years. The six inch apron on the other end is still perfect. I had a D8K at the time and I would pull a hyster lowboy with the Cat on it into the barn with no cracking. If you can spring for the extra thickness, I would go with 6 inches. That also gives you more wiggle room for the rebar to not be too low or too high. The best thing the guy did that helped me was force me to install metal strips he called keyway into the edge of the aprons with bent pieces of rebar in the holes. Now when I get some extra dough, I just dig out the end and straighten the rebar and it is ready to pour without having to drill holes for the new rebar to tie into the old slab. My concrete knowlege and 50 cents will not buy you a soda anymore.

Unlike women, with concrete, the thicker the better.

[41chevy]

4" thick is considered minimum here. My slab outside of my shop is 25x25 x 6" thick 4000 psi fiberglass reinforced concrete with an expansion joint at 12' 6" and steel screen to prevent cracking. We did a 6" layer of compacted 3/4 to 1" gravel before the slab to prevent frost heave. Took about 9 yards as I recall and the Fiberglass reinforcement was only $100. more. One thing I wished I did was a slight crown for drainage. The Cat that holds my mail box in my avatar I tugged it all over the slab and no problems. Paul

[tanbuddy]

I do a lot of concrete work for a living, The minimum i would do is 5 inch with steel reinforcemet if the truck is going to be empty, but i would rather do 6 inch.

The last time i did a municipal garage floor for plow trucks and such it was 12 imch with rebar at 4 and 8 inches high. That was way overkill but its what the township wanted

[Rob]

I did 9.5" 5000# fibermix in my shop floor. I was concerned about jacking a loaded truck up with a floor jack.

Rob

[leversole]

Thanks all...looks like 6 inch is the minimum...small price to pay for the extra insurance!

[609albert]

5.5 / 6 " should be your min. and at least 4000# with wire, our pole barn(a MORTON) 42X52 we had to build up with recycled concrete 6 to 18 " took about 50 tons ,power plate compact in 2" lifts, cover with plastic, wire .

another important item is the expansion material, we used a recycled rubber material 6" high all the way around

the building including around each post , we did all the prep work and the concrete crew did the pour/placement started

at 7am and they where gone by 2 pm 40 cu yd including aprons , (7 GUYS)come back next day and saw cut joints in.

HAS NOT CRACKED IN 5 YRS.

[1958 F.W.D.]

I am a building inspector by trade. Usually detached accessory buildings dont have to follow any codes, but considering the weight you are going to place on the floor, I would do no less than 4" stone and 6" of 4000psi with #4 bars 16" on center each way. I have heard good things about the fiber-reinforced concrete but have no experience with it, dont see it a lot around here. One thing I do highly reccomend though- will you be heating it? Have you considered a hot-water heated slab???? The Volunteer FD here did a heated slab when they built their new building and they love it- it is very efficient, and not hard to do yourself. You would need a hot-water heater of course and a system to pump it through the tubes.

[MACKTRUCKS4]

I too would go with floor heat. I have it in my entire house, including basement, attached garage, main floor and 2nd floor. There is nothing like it in the dead of winter when you have the floor warm and open the door to drive something in or out. and within minutes of closing the door, you can still feel the warm floor. I t does not cool down fast so it does not take long to warm back up. Also you can heat the water with anything you like, coal, wood, oil,and even waste oil. It is not hard to put the tubing in now and hook it up later.

[fxfymn]

There is a six inch minimum if you ever decide to do a four post lift. I used 4 inches of fiber reinforced on my floor and I have not had any substantial cracks. The key factor is in the base prep since concrete is only strong in compression with little or no strength in tension. In other words if any of the base settles and leaves a void cracking and settling of the pad is almost inevitable. Reinforcing is used to provide some tensile strength, but what you really want is to avoid having to rely on the reinforcement for crack prevention.

It costs a couple of hundred bucks, but I would get a soil test done to make sure you do not have any shrink swell soil problems. If you do than you will need an engineered foundation. This costs more, but the result is a proper foundation that will do the job.

Make sure the base is resting on undisturbed soil or have it properly compacted and tested to ensure the compaction was done correctly. Generally the codes allow the use of sand or crushed rock under the slab. Either will work, but I prefer crushed rock. (usually 57 or 68)Make sure the base layer fills the foundation completely and I always provide mechanical compaction as well. Yes; its belt and suspenders, but you only get one chance to get this right.

I also prefer to use a poured foundation as opposed to a block foundation for the same reasons. A properly poured 8" wall will never move so your base will never move either.

Due to an elevation difference I had to account for I used 200 tons of 68 under my slab. That's why I'm certain I will never have a cracking or settlement problem.