Is rebar needed for concrete swimming pool decking?

Question

I am having an existing concrete deck torn out around my in ground pool and a new one poured, my contractor removed most of the big chunks of concrete but left a bunch, some small some large...
I ask him was he planning to remove the chunks and put down rebar, he said, "No, no one does that anymore" And he was going to pour the cemet over the chunks, does this sound okay?

Answer 1

Wire mesh reinforcing should be fine. All you need is to reduce cracking. All portland cement concrete cracks. Be sure no steel in the slab touches the ground or sticks out of the surface. It needs at least an inch of concrete under it and over it.

Be sure he leaves cracking control joints, and expansion joints if it is a large placement.

The old material should either be removed or beaten down into the base. You need a uniform thickness in the new work, and you don't want point loading. I.e. it should go down over a smooth surface of gravel.

Check out his history with the State. You will need his contracting license number, which any reputable contractor will have given you up front, but should be on his card, his paperwork and in any ads he has in phone book etc.

If you are afraid of calling him on deficient work, hire somebody to watch it for you. Ask the building inspector (if a permit is required) to tell you where to look for one.

Answer 2

Rawstuff 007 has it right. The contractor is probably trying to save on the amount of concrete he is pouring by leaving chunks of existing concrete in the form. If the new concrete is going to be slurried around the existing chunks, such that the old concrete is part of the new decking, this creates weak points in the decking (where old, cured concrete contacts new, wet concrete) that will be susceptible to cracking.

When pouring a slab of concrete like that, all of the existing material should be removed down to a depth of at least 4 inches. Then concrete reinforcing mesh (that Rawstuff described) should be placed across the entire area where the concrete is going to be poured. If not, the decking may not be to code when it's complete.

Answer 3

You definitely don't need rebar, but check with your local city building inspector, they may require a wire mesh, or better still, you might. By the way, find out if you need a permit and get one yourself if you do (you’re the one on the hook for that). If you need a permit and your contractor said that you don’t, he is trying to pull a fast one on you. A permit means inspection by the city and that means he will get caught if he is trying to cut corners. Remember, the inspector works on your behalf to ensure a minimum level is met.

As for the old concrete, it is OK to use broken concrete like gravel, so long as they pour at least 4” of new concrete over it and not use the old concrete as filler to save on concrete. See if your municipality allows it.

Concrete is relatively cheap. If your contractor is trying to cut corner and use the old chunks as filler to save on concrete, I would seriously question his reputation. Put the job on hold and call other contractors to find out what is best practice in your area and to determine how much it would cost for them to complete his work. If he is cutting corners here, where else is he cutting? Your contractor might also shape up if he knows that you are an informed consumer.

Answer 4

No. All the garbage cement needs to be removed and yes you do need rebar or reinforcing screen. Also make him leave a stub of rebar stuck out of the slab for electrical grounding. All the rebar must be wired together with simple twist wire also. Any metal items in or near the pool must be bonded together for electrical grounding. Ladders, diving boards, ect. If you don't do all that now, you will not pass inspection and may have to tear out the whole slab to do it over. The installation will have to comply with the new electric code which has gotten much more strict. Check with your building department or inspector for more information.

Answer 5

You already have a bunch of great answers. So I am only going to re-emphasize the stuff that was already said.

Re-Bar is not needed for a small deck.

Expansion joints are needed or at least relief joints to induce cracking. these can either be tool cut or you can have them use a crack inducer by WR Meadows.

Welded Wire Fabric is recomended.

Finally, the area where the concrete is to be placed should be CLEAN AND FREE OF DEBRIS!

I don't know who this contractor is but short cuts lead to inferior work. You are paying him to do a job. But if you want that job done a certain way then you can demand it - but it may cost you sometimes.

$ = Scope, Scope = $

Answer 6

You really wont need rebar since its a deck. As far as the chuncks that is kinda questionable. If the chunck is going to sit taller than the concrete I would question that. As far as the rebar thats a little overkill. You might want to suggest some wire mesh even though not really required(get sheets if you do they are much more user friendly than the rolls.) That is a little lighter and will help from future cracking.

Answer 7

I would think the rebar should be laid down. It always helps to reinforce the concrete. The chunks really shouldn't matter. They are concrete also. It will just save him some money because he will not have to pour as much new concrete. If it were me, I'd insist on the rebar..

Answer 8

Definitely NOT!!! Get that garbage out of the concrete form before he pours.

A concrete walkway around your pool doesn't need rebar, but it does need a reinforcing screen. the screen has square holes in it abour 4" x 4" or 6" x 6".

Also, he needs to place expansion joints in the pad. You cannot just pour one continuous pad. It will split and heave, and look like hell after one full season of frost heave and spring thaw.

it real easy to place the screen in a concrete pour! the expansion joint is easy, as well, so I don't know why he isn't using it!!

Answer 9

If this is by a pool you better get ahold of an inspector. Most pools are required to have a grid to ground it. The deck may fall under the same rules. Dont let him pour til you get facts.
When dealing with pools you want everything to have equalpotential.

Answer 10

Better to remove the chunks - new concrete will not join with the old.