# big crack in 2 week old MONO Foundation



## denick (Feb 13, 2006)

Did he state that reinforcement was required to meet code?


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## stagger19 (Mar 12, 2006)

no, when I meet with the inspector in Feb I was half way thinking about doing the pour myself, and I asked if rebar or remesh was needed to meet code, and he said NO.

So the pour meets code, but im concerned on the crack being a structural issues once the weight of the garage, a car parked on the slab, and a few frost and thaw cycles.


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## denick (Feb 13, 2006)

Stagger,

Just to recap everything.

You asked the building inspector what was required by code for the pour and reinforcement a while before you had the work done.

You hired a concrete contractor who said he would pour the slab (his description here) which meets code as the inspector told you so you said yes.

He did the work as you and he agreed.

?You paid him???

If this is the way the job has gone in my opinion, 
Talk to the contractor. See what he thinks. What is he willing to do.

Then see what you would do as the next step.


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## stagger19 (Mar 12, 2006)

Yes, I made up and submitted plans for my garage.

The inspector approved of the plans and issued me my permit.

I subcontracted out the concrete and hired a concrete contractor
to pour my 16 x 24 mono slab.
I showed him my plans and he agreed to pour the slab.

After he dug out the footings, I called the inspector around to ok the pour. The building inspector blessed the pour, and the next day the concrete guys poured the slab.


So at this point im waiting to hear back from the Concrete contractor, and Im gonna try to get the building inspector around on mon or tues to look at the slab and see what he thinks.

Thanks for all your help, I will post a follow up early next week as to what the outcome will be.

Thanks again.....


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## denick (Feb 13, 2006)

Stagger,

Good luck,

I don't think you have a structural problem as it would pertain to the settling or shifting of the foundation because of the weight of the structure. You have plenty of mass to support the load. The issue it seems will be cracking that might allow for water penetration that would cause deterioration of the slab.


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## K2 (Jul 8, 2005)

A 16x 24 is going to crack within 2 weeks. Planning where it cracks will be is the only issue in my opinion. 

Rebar, mesh, etc. doesn't do anything until it goes under "tension" or the concrete cracks. Pre stressing the reinforcement or putting the steel under tension in advance is a way to try to eliminate cracks but that is rearly done in residential in my area.


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## PipeGuy (Oct 8, 2004)

Rob 53 said:


> A 16x 24 is going to crack within 2 weeks.


That simply does not have to be the case. Adequate reinforcement, proper mix design, proper placement and proper curing will produce slabs free of shrinkage cracks. It's done everyday all across the country on slabs vastly larger than 16 x 24. It takes more than some basic carpentry skills, the ability to order a truckload of concrete to produce good concrete work.


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## K2 (Jul 8, 2005)

PipeGuy said:


> That simply does not have to be the case. Adequate reinforcement, proper mix design, proper placement and proper curing will produce slabs free of shrinkage cracks. It's done everyday all across the country on slabs vastly larger than 16 x 24. It takes more than some basic carpentry skills, the ability to order a truckload of concrete to produce good concrete work.


In my opinion anyone who has poured resi concrete for living would agree that a 16x 24 requires at least one control joint across the long dimension. When the control joint is in place, people don't even know the slab ever cracked. 

As I said before, reinforcement, unless prestress, does nothing until it is stressed. In normal residental construction the only way to stress a piece of rebar or to put it under "tension" is for the concrete to crack. Well that's the way the engineers explained "tensile and compressive properties" of concrete to me and it seemed to make sense.


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## Joasis (Mar 28, 2006)

I have poured a lot of mud, and it is not in my experience that a 16x24 would crack in 2 weeks, or ever. If the framing goes up within days and depending on the time of year, I might not cut it at all. The Oklahoma summer is when control joints need to be cut on time...rest of the year, we can wait a week or more.

There are a ton of variables that affect concrete. I have house floors that did not crack with much greater areas, and I have seen sidewalks and patios crack in days. The nature of concrete is to crack for sure, but it doesn't mean it happens. The way a floor is screeded and finished has a lot to do with cracking.


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## stagger19 (Mar 12, 2006)

I agree with the control joints. A slab that big should have a weakened predetermined area to crack. Concrete expands and contracts so its gonna crack eventually.

my crack doesn't just run horizontal across the slab, but also vertical down the side about 6 ", so I'm not sure if thats shrinkage or settling?

I'm just worried now water will get into the crack and with frost and freeze cycles make the crack worse and deteriorate the slab prematurely.

I guess theres no way to tell now if the slab will be stable now or continue to crack???


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## Joasis (Mar 28, 2006)

Drive your pick-up on it, close to the edge. From your pictures, the crack is pretty large, and splitting down the footing. It would be interesting to check the floor level with a laser and see how much it dropped.


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## Glasshousebltr (Feb 9, 2004)

Stag, in that last pic it looks like the fella used block as a retainer along the inside of the ditch to save on crete.:no: I hope thats not the case, cause that my friend is a big no no. If he left that in place, added to the fact of no rebar or footing tamp....bingo baby. The footing settled durring cure and the 4" at the top lip offered no additional support. Shoot the top, I'll bet one side or both beyond the crack are down. If not the crack developed durring the pour and just wasn't visible.

I never fill inside on a mono ledge. That contour has a lot of support to offer. It cost a bit more in crete, but I've done hundreds of monos, at about that size and never had one crack.......ah....yet.:whistling

Is the crack at one end of that retainer?

Bob


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## stagger19 (Mar 12, 2006)

Ive had nothing but problems from this guy from day 1 when he arrived on site. His uncle does the estimating, and quoted me 6K grand to do the pour. When he arrived the first day, and shot it with his transit, he said because of a slope, the one corner was off by 16" diag from the high corner. 

So he was gonna pour a footer and do block for $7,800 and I said I cant afford that much, so he said ok, I can still do a mono and put in some 12" block to help fill the void to eat up some concrete for $6,500.

As you can see in the pic, yes he did leave the blocks in there to fill the void up. He said it will hold with no problem.

The building inspector saw the block and said it would be fine.

http://i50.photobucket.com/albums/f338/stagger19/monoforms.jpg

The crack runs across the slab at about half way down the 24ft side


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## Glasshousebltr (Feb 9, 2004)

First off, I wouldn't rely to heavily on advice from a building inspector in this dept. No one can predict if or not that would hold. It might have actually worked just not this time.

A rule of thumb I follow on crete: If there's question, I change it to overkill.

Your last pic didn't hit.

Bob


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## Glasshousebltr (Feb 9, 2004)

Here's another thought: Just at a glance I'd say he saved about 3 to 4 yards of crete with the retainer. If we highball that he saved about 400 bucks. What do you think it cost him in T&M to fill it? He put his and your names on the line to save a couple hundred bucks. Not to smart a fella I'd say.

Bob


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## Glasshousebltr (Feb 9, 2004)

Stag, after looking at the forms again, please tell me he didn't poor the apron and mono in one shot.

Bob


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## stagger19 (Mar 12, 2006)

He did put an expansion joint between the mono slab and the apron

well just to show you what else he messed up...

I showed him my plans before they even started work, he knew I was gonna frame out the front wall for a 9ft garage door. He didnt even build to my plans for the j bolt locations or the garage door framing.

He put in what he said they call a wind tray, where there is a cut out where the door drops down into to stop wind from blowing under.

Well he made the tray 11 ft wide, so I told him im gonna have trouble framing out for my trimmers and kind studs as the sill plate would be at 2 different levels. Keep in mind the apron is 9 ft wide, same as the garage door, look at the wind tray he pourded!

Heres a pic to better see what im saying. you can also see the patch he did, hope that holds up also!

So he glued a patio block in there, and it looked like crap, so after he got all pissy with me, he finally pourded a 1.5" overlay over the foundation.

http://i50.photobucket.com/albums/f338/stagger19/16x24monoslab.jpg

http://i50.photobucket.com/albums/f338/stagger19/patch.jpg


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## Glasshousebltr (Feb 9, 2004)

I think he might need a _'wind tray'_ between his ears.

Did he shute that 1.5 over the crack?

Bob


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## stagger19 (Mar 12, 2006)

the wind tray patch is in the front of the bilding, the crack is on the right side edge half way down


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## Glasshousebltr (Feb 9, 2004)

Ok I got ya. For a second I thought he added 1.5 over the whole floor. Sometimes it's tuff to tell what a fella like that might do.

I'm not 100% sure but I think 3 coarces of rebar in a footing are manditory just about everywhere. Some one else want to chime in on that?

Bob


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## maj (Mar 13, 2006)

stagger19 said:


> thanks for all your help guys in this matter, I really do apprecaite all your help! :thumbsup:
> 
> I was just wondering if there is a code violation here...
> 
> ...


I've never even heard of a windtray  must be a regional thing. When I saw that I didn't know what the H it was.. I still don't quite comprehend the purpose.

And I can't believe rebar is not in your codes.


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## Tscarborough (Feb 25, 2006)

Stagger, you forgot the most important one, the one that would have enabled you to finish your garage, "as is":

2 to 4 #4 Rebar in the perimeter beam and at least 10/10 10x10 mesh on the slab.


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## Tscarborough (Feb 25, 2006)

A windtray is a good thing. It is analogous to a brick ledge, in that provides some protection against wind and water. They are pretty standard in Texas.


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## Glasshousebltr (Feb 9, 2004)

Ts always comes up with this serious $hit.....I wonder if he's sitting by the fire with his robe and pipe right now.:w00t::jester:

Bob


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## Tscarborough (Feb 25, 2006)

BTW, I get 15 yards, not counting the approach apron.


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## Glasshousebltr (Feb 9, 2004)

Yea but Ts, ya forgot to math in the sidewalk in front of Captian Concrete's house.

Did he peel off quick behind the last truck Staf?

Bob


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## A+Carpenter (Apr 19, 2005)

stagger19 said:


> thanks for all your help guys in this matter, I really do apprecaite all your help! :thumbsup:
> 
> I was just wondering if there is a code violation here...
> 
> ...


How many times does this need to be gone over to get to the point?. The answer is clearly posted in what is wrong and what can be done to fix it.


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## Glasshousebltr (Feb 9, 2004)

Rutt Row....Does somebody need a nap.:w00t:

Bob


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## ConcreteGuy (Jun 10, 2005)

Good concrete has one singular quality. It gets hard. 

And in that process it shrinks, which produces cracks.

Cracking in concrete is tollerable and controllable by many means and methods as required by conditions.

The reason for control joints in a slab is to produce an aesthetically pleasing appearance of normal concrete shrinkage cracks. 

Proper design will control cracking, but it's all downhill from there. In other words, it's up to knowledgeable and professional material placers to know what they are doing.

EDIT: This is no slam on producers of concrete products, from the batch plant to the laborer who knocks it down. If you misunderstand my tone, I mean to educate you on the product and how you can handle it better. And more specifically to the point of this post, how you can defend yourself against over-reactions to normal properties of this product. The concern of this thread is not about structural integrity but, rather, about aesthetics. The consumer needs to know that cracking is normal, however, that the contractor, or design, failed to control it. Remediation is expensive either way. How much you value this customer and your own sense of culpability are factors. Epoxy joint fillers are commonly specified for "control" joints and you could offer this treatment, apart from breaking out your concrete erasers (jack-hammers).


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## Tscarborough (Feb 25, 2006)

That is all well and good (and true), but the concept of reinforced concrete allows for and makes usable concrete that will crack. Without proper reinforcement what you have is a bunch of separate sedimentary type rocks formed into a pleasing shape with no structural integrity whatsoever.


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## PipeGuy (Oct 8, 2004)

Tscarborough said:


> Without proper reinforcement what you have is a bunch of [junk] formed into a pleasing shape with no structural integrity whatsoever.


And it never ceases to amaze me what passes as "proper reinforcement" in housing construction.


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## stagger19 (Mar 12, 2006)

Well here is an update I thought u guys would have to here...

The building inspector came out today to inspect the foundation,
and when I mentioned about the fill on top of the grass (showed him the pic), the busted up concrete in the trench, and no 45 deg angle transistion on the mono, he didnt seem to think it would be a problem. He mainly was worried about the cracking and said it needs to be cut.

So this is where you guys will NEVER Belive what HAPPENED!

So I call the contractor up and left him a message that the inspector wants the Jbolts fixed and the slab cut. Didnt hear from him, so I called him back a few hours later to see if I can get a hold of him and he answer the phone and just totally flipped off on me. He was screaming at me so loud, people down stairs heard him yelling. So I was trying to calm him down, and tell him what the Inspector said, and he just kept yelling and I couldnt even get a word in, so then he said "I will come around and cut your F-Ing head off" he kept screamed some more, and hung up.

Needless to say u dont run a business like that, I wasnt yelling or nothing, I was being firm, but I was totally calm, so after thinking about what he said, I knew I had to file a police report on this idiot.
You cant threaten people like that, and u surely dont run a business like that!

Talk about a Contracor from HELL!


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## Tscarborough (Feb 25, 2006)

You have that right, and it isn't rocket science; the principles have been known and codified since the 1920s at least.

Fibermesh is a great product, when used in *addition* to rebar/wire mesh. It is used to prevent hairline cracking and to increase the overall flexural strength. It can not be used in place of rebar in a structural concrete slab, though it may suffice in a non-structural application (sidewalks, for example).


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## Tscarborough (Feb 25, 2006)

I think your inspector and your contractor deserve each other. What does your contract say about warranty?


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## stagger19 (Mar 12, 2006)

contract doesnt mention warranty


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## Tscarborough (Feb 25, 2006)

You have a contract stating that he doesn't have to use reinforcing steel, there is no warranty and, your inspector is ignorant enough to ignore poor fill, poor compaction and the lack of reinforcing?

You have learned an expensive lesson, my friend.


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## stagger19 (Mar 12, 2006)

LOL, live and learn. Just NEVER thought Id have a Contractor from HELL!


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## Joasis (Mar 28, 2006)

I think you have legal recourse, you have enough expert opinion here to KNOW he screwed up the job, you have a great set of pictures to back your claim. Have a lawyer send him a nastygram saying fix it or suffer the expense of legal action.


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## Tscarborough (Feb 25, 2006)

Joasis, he would have a case except for the fact that he has a contract that does not require steel reinforcing. With reinforcing, all of the other issues would not matter, the slab would still perform as expected.

As it is, the slab is performing as well as could be expected.


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## stagger19 (Mar 12, 2006)

Well I figure lets see what happens tomorrow.

After he threaten me, I called him back (I was pissed now) and he answered the phone, and said "dude i will be there tomorrow" and hung up.

So hopefully he will stop by and cut the control joints.

And if he doesnt, i figure I can always wreck another 1 of his nights, and maybe he can threaten me again ( I will tape it this time), and he can have another police report against him to show up for court.


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