concerete guys step up

[truckdude239]

looking at getting a 30x30x4inch spad poured for our shop we looking to build we where told to grade it and add 4 in of washstone under it but we dont know anything about doing the rebar anyone explain how to set up the rebar?

[NONHOG]

They make small ceramic risers to hold the rebar up off the ground. I suppose you could make something to hold it up.

You tie the rebar together with wire so it stays in place.
Where you get your rebar you should be able to get your other supplies.
You'll have to look up your local code for spacing and size requirements.
I went with wire mesh.

No expert, was a concrete "grunt" over 20 years ago. Hope this helps !

[rwolf9653]

Wire mesh is the way to go. Lay it flat and as you rake the concrete you just pull it up with the rake and the concrete will keep it up.

[LEEVON]

I'm not a residential guy but for a 4" slab I believe that normally you would use 1.4x6x6 welded wire fabric. If you are concerned with cracking then a grid of #4 or #6 rebar on 12" centers would help. You could do the fabric and then just use some bar at the entrance where you plan to drive in. Use concrete bricks or "chairs" to hold it up, the chairs look like caterpillars. Of just pull the mesh up to center like the OP said, just make sure it doesn't get near or penetrate the surface.

[Bishops Trucks]

wire mesh works just fine. Pull it up into the concrete with your rake as you go.

[Hottrucks]

ok here goes!!!!!!!!

you want to build a floating slab

the slab grade should be ABOVE the yard grade ( at least 4") so water will flow away from it that is most important!!

second grade the area so that your slab is 4" thick..... aound the perimiter you need to have it dug out so that the part that supports the walls is thicker..personal I would recomend doubling it to 8" deep and about a foot wide also rent a compactor and USE IT!!! over and over you can't do it enough also when your doing it spray it with water it helps compact..like a piant job the top is only as good as the bottom

third...fiber vs wire vs rebar...personally I would go with the wire but have had great luck with the fiber they add to the crete...also plan to have the floor stress cut so that if it does crack its controled..if you choose wire or rebar use cement bricks to hold the wire/rebar up pulling it with a rake works but then you have no idea if its covered with 1" or 4" of crete a brick is 2" and consistant

if you have any more questions just ask

Jeff

[bhoeger70]

3/8ths or 1/2 rebar on 2 foot centers, place the rebar on broke up cement blocks. I prefer to dig a 12x12 inch footing around the perimeter and put a 1 inch grade to the middle of the slab. Buy or rent the wire twister and use the prefabbed wire ties get the longer ones(6-8 inch I think). Also run at least 2 runs of rebar around the perimeter, cut some into four foot long chunks and bend them into a U shape then pound the ends into the ground around the perimeter at about 4-6 foot intervals and tie those two runs of rebar to those. Have enough poly around to cover the slab when you are done finishing it in case it rains.

[Hottrucks]

3/8 wire is planty on a 4" slab the bar around the out side is a good idea ...you can get 1/2" bar and bend it on the ball of your truck where it needs to be bent....besure to go at least 3 feet around the corned and over lap about a foot or so and tie it together

alot is going to depend on what type of building your going to put on it

I would recomend at least a couple rows of blocks this will keep the water from spalshing up and rotting the sills..also will give you some ceiling height..and allow you to wash the inside floor without wetting the walls

[Hottrucks]

read this

http://www.concretenetwork.com/concrete/slabs/

[truckdude239]

okay heres the deal looking at installing a lift in the shop at some point. cement company says i need rebar plus building codes require the fiber to be added to the cement and was quoted 1300 to pour and float the cement

[Hottrucks]

you need to get the location for the lift and be sure to dig out below the lift points ..I would use a 2 foot square under each leg of the lift...also rebar in a # pattern under it...the rest of the building I would think that 2' on center would be plenty...you may want to check with local code on bar placement..I find it hard to beleive that they make you use fibre even with the bar??? either or ???

[chickenwing]

Just went through this. Research out the lift you want. Now determine how wide your bay opening is gonna be. Redetermine what lift you want. Determine what your sidewall height will be. Redetermine what lift you want. Sidewall height needs to be a bit above 12' for a 2 post above ground lift. Determine how deep into building lift will be based upon your longest vehicle. Nice to close a bay door while truck is on the lift. Now ya might can figure out where your max thickness needs to be for your lift. Bendpak specifies only 4" of 3000psi rated crete for their 10000lb 2 post. Why make it all only 4" when you can go a bit thicker on your load bearing areas? Minimal additonal cost that way. I went with fiber no rebar. Pad as a whole is non-load bearing on mine as I have a pole constructed building. So I poured no footing around the perimeter. (If it I did go stick built it would have had a footing. Doubt inspector would allow you to go without one if that is the case.) Did go a bit thick on my primary service bays (6"-8"). Did cut control joints in mine on 10' centers while it was still green. Totally agree with a raised sloped pad, particularly if you reside in a wet climate. Go with a vapor barrier below the concrete too to prevent sweating. Know I didn say a darned thing about rebar but hope I helped.

[chickenwing]

Wow, that $1300 doesnt include the concrete. Right? Edit: Pic in your avatar looks kinda suburban. Any chance you can declare it an agricultural building? Lotta building code requirements go away with that designation... Have you talked to your inspector? They can be helpful when you are preplanning. Show em specifications required by lift manufacturers and make sure they know this is for a non-commercial operation. Maybe they might forgo the rebar or the fiber.

[truckdude239]

no it inculde s it

[Hottrucks]

you need about 9.5 yards of crete...around here its $135 a yard plus fees

so thats a good deal

[truckdude239]

was told 11.5 yards at 106 dollars a yard

[NONHOG]

Talk with your concrete guy and tell him your plans and concerns.
I'm glad I did, I assumed some things and was wrong.

Read up on vapor barriers, touchy subject but you get to decide not the contractor.

Consider doing the compacting yourself, you'll probably spend more time at it than the contractor will. (?)

I cut control cracks on my floor with a skill saw and would never again.
rent a walk behind or pay someone to do it.

Good luck, keep us informed !

[Hottrucks]

good price on crete...you can figure your yardage...LXWXH/27=yards..I just did a quick guess be sure to figure your edges and pads for your lift....and remember theres always some left over so if you need a wak or something have it ready