Replacing failed concrete patio question...

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Flyingbuffalo

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We recently bought this house. It has a 12' X 24' concrete patio that has settled and cracked in several places. We hired a concrete contractor to bust up the old one, haul it away and make a new one using packed road base, rebar and 4000 psi cement.

They broke up the old patio and hauled away most of it, but there's still quite a bit left and they are telling me that the road base can be laid over the remaining pieces of concrete and tamped down. Some of the pieces are rather large and I'm finding it difficult to believe that this is an acceptable procedure. I have attached a photo with a tape measure as a 12" (footlong) scale.

I'd like them to cart away the remaining pieces of concrete before spreading the road base. Can anyone offer any insight into this dilemma? Thanks!

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oldognewtrick

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Do you have a written proposal with the scope of work stating they will haul away all the old debris? Was this discussed with you before work began?
 

Snoonyb

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We recently bought this house. It has a 12' X 24' concrete patio that has settled and cracked in several places. We hired a concrete contractor to bust up the old one, haul it away and make a new one using packed road base, rebar and 4000 psi cement.

They broke up the old patio and hauled away most of it, but there's still quite a bit left and they are telling me that the road base can be laid over the remaining pieces of concrete and tamped down. Some of the pieces are rather large and I'm finding it difficult to believe that this is an acceptable procedure. I have attached a photo with a tape measure as a 12" (footlong) scale.

I'd like them to cart away the remaining pieces of concrete before spreading the road base. Can anyone offer any insight into this dilemma? Thanks!
Is this a "concrete" contractor, or someone who just pours driveways?

Ask them what size of rebar, the rebar spacing and what is the "cost" in the pour?

"Cost" in this case is the amount of concrete between the base material and the center of the rebar, bar, and should be 2".

How does he plan to attain that over nondescript, unconsolidated rubble, in a 4" slab?

A quote for a concrete, poured-in-place, slab contains "3" dimensions, you have provided 2.

The other is "thickness."

If the proposal was for a 4" slab over "roadbase," what is the composition of the "roadbase", and how thick is it?
 

mudmixer

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"road base" is a local term. Usually it is fine enough to consolidate and compact well. It may well be good to fill the voids in the material left during compaction and provide a satisfactory level surface to pour concrete over to the thickness required. - They just used road base to "choke" the compacted surface. It is done often and is usually not a specific process procedure of performance level that can be measured specialty for a small, non-critical use, since the concrete thickness over the compacted surface is what counts.

Dick
 

Snoonyb

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"road base" is a local term. Usually it is fine enough to consolidate and compact well. It may well be good to fill the voids in the material left during compaction and provide a satisfactory level surface to pour concrete over to the thickness required. - They just used road base to "choke" the compacted surface. It is done often and is usually not a specific process procedure of performance level that can be measured specialty for a small, non-critical use, since the concrete thickness over the compacted surface is what counts.

Dick
That's all well and good for 6" slab, but the forms appear to be 2X4, so using sand as the "roadbase," what is the thickness of the concrete, 1.5-2", what's the "cost" of the rebar, parking sufficient for what size of vehicle.

I'd run the guy off.
 

joecaption

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I've never once seen anyone use rebar in a drive or walk way slab.
If anything it would be wire mesh.
 

Snoonyb

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I've never once seen anyone use rebar in a drive or walk way slab.
If anything it would be wire mesh.
While 6,6,10,10 WWM is a standard, here on the truly left coast, #3 rebar is not uncommon.

What's interesting to me, where was this poster, prior to the agreement being signed.
 

nealtw

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We see rebar in driveways here all the time no one has ever givin a good reason other that, if the ground settles, in that case you want a self supporting slab and you need a lot more steel.
The concrete waist is fine as long as the fill on top still gives you required depth of concrete.
 
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Chris

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Those chunks probably won't cause any issue but if it were me paying for the service I would want anything bigger than 3/4 Rock pulled out. It's not that much work and base is cheap.
 
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Chris

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As for the rebar here in ca we see it about 60% of the time. I personally don't use it but I also make sure I have a properly compacted sub base before I pour and I use a seven sac mix. Never had an issue.
 

slownsteady

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Is that 2x4 supposed to be part of the form or is it just marking the area temporarily? I can't imagine that being part of the form for a new pour.
 

slownsteady

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It looks there is a gap between the board and the ground, and I think I see a nail facing in towards the pour (makes it tough to remove the board). It's hard to tell from the pix, but it doesn't seem to give the required depth above the chunks. I would expect it to have more support stakes to keep it from bulging too.
 
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nealtw

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It looks there is a gap between the board and the ground, and I think I see a nail facing in towards the pour (makes it tough to remove the board). It's hard to tell from the pix, but it doesn't seem to give the required depth above the chunks. I would expect it to have more support stakes to keep it from bulging too.
You throw a 2x4 down to define the area to put the gravel you move the 2x4 and compact the gravel, then you form up. So elevation that we can see there is non information. the other picture of the window well and the curb looks like the elevation is to high.
 

slownsteady

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Thanks. I didn't think it could be part of the form, but I guess it wasn't just incidental.
 

frodo

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what does the contract say ? plan and simple

bust and remove or bust and partial remove ?

I dont see anything wrong but 1 thing.....make sure no big chunks are stopping you from haveing the 3 1/2'' of concrete coverage.

take a string. pull it from form board to form board. measure from the string down to the ground in multiple spots

if you cant measure 3.5'' take pictures.
 

frodo

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you know how it is..they ask a question then flitter off to where ever land
 

Snoonyb

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I mean, this isn't instagram, or twitter, or facebook, (should have bought it at $18 and didn't buy apple at $7.........damn..........), you can't suffer a lose of self esteem by sharing your shortcomings with people you don't know.
 
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