Introduction: Jack Goodban, 25+yrs. in the trades, self proclamed “not stupid”, still able to learn from from intellengences far greater than my own, Miller Lite, and I also leap tall buildings in a single bound.
MFCH (my first complete house) problem.
I supervised this concrete slab being poured. First the footings, then the slab. Lots of steel per structural engeneering.
My slab still split, seperated 3/16″, and heaved right down the middle of the kitchen and dining room where it called for ceramic tile.
How would you prevent and/or repair this problem.
Respect,
Jack
Replies
Did the middle heave, or did one side drop?
So it was built per engineered plans ... was it inspected before the pour? Then I would call the engineer to the site and ask him what happened.
I'm sorry, I thought you wanted it done the right way.
The footings stayed level around the perimiter and down the center. It raised in the field only.
The structural engereer said the city didn't want a soils report, so its not his problem.
Jack
"The structural engereer said the city didn't want a soils report, so its not his problem"
What complete B.S. He is responsible for producing a design that will work. It's not up to the city or his mommy or anyone else to tell him when a soils engineer might be advisable. He did not rely on a soil report in his design, therefore he assumed responsibility for analyzing and approving soil conditions.
Unfortunately you may need to hire a lawyer and a failure analyst to pin this on him, but I bet they could, based on what you are saying.
A failure analist? I will use that term, Thank you.
And if the problem comes back, I'll find one.
I had a half a?? repair done with epoxy and grinding, then set the tile.
I know it might come back and I will have to honor our warranty.
Any failure analist out there? I know there is!
Jack
Edited 7/28/2005 12:45 am ET by Goodban
I agree 100%. The engineer charged what was probably a fair chunk of money to design a foundation , and when he sold you the plans he was saying "this is what you need to support your house on your lot". Talk about trying to dodge responsibility! I think I would talk with a lawyer to at least see what your options are. It was the engineers responsibility to gather all necessary information prior to completing the design. He should have told you that you needed to pay for a soil test. And thenm he should have made a 10 minute visit to the site before the pour to confirm that the steeel was per the plans.
The person you want to talk with might also be called a forensic engineer.
I'm sorry, I thought you wanted it done the right way.
What complete B.S. He is responsible for producing a design that will work.
Nice idea. While I certainly don't brag on the 3 structural engineers I dealt with getting our place going, that was 100% of the local talent.
One was a total nitwit, but I only wasted $125 (would be $300 today) on him. Another designed the roof, straight from a bar joist table, but had the state stamp I needed. The third designed the walls and footings to support our 240 ton roof. Nobody gave any consideration to soils or site. When I asked, I was told it'd work just about anywhere. As far as they were concerned, they did the structural analysis and that was the end of their responsibility. Site applicability was solely my responsibility. Our building dept. ignores such things. Hey, I had engineering.
Looks to me like Goodban's up the creek. PAHS Designer/Builder- Bury it!
As far as I know, a design on paper with no site information given lets the engineer off the hook. If he included the site information on the drawings then it's assumed that it's engineered for the site.
The plans call for the bottom of the footings to be at undisturbed soil (undisturbed since when?).
In the field, where the heaving has occured it calls for 3" of gravel, 6mil. vapor barrior, then 4" sand.
And with the 4" steel reinforced slab, I thought it should be bullet proof.
I live in wichita falls texas (north texas). Built my own house but subcontracted the slab of course. I told him I wanted 24 inch beams and 5/8 rod. within six month I noticed cracked brick. Then another, then another. Then the doosie. I used stain concrete in my entry room. I trimmed it to perfection. It was gorgeous! A crack started right down the middle of it. It comes and goes so much that the the crack is now chipping out. Horrible looking now.
RED CLAY I should have had an engineeded slab.but everyone told me it was a waste of money. "just Beef it up" they said. ha
good luck
Geeze!
>> The plans call for the bottom of the footings to be at undisturbed soil (undisturbed since when?). <<
Since before birth of Christ... Pick a time... anytime before that... anything after that is not undisturbed! ;-) Matt
Almost sounds like a clevar way to cover your a$$ if your foundation design fails.
Don't know about that, but during foundation excavation the basic idea is to dig down to never been dug up, firm earth... If that is not feasable, additional engineering is in order. Also, you often don't know until the digging is well under way.
Matt
Edited 7/30/2005 3:16 pm ET by Matt
In my case, I didn't know even after the digging was complete. Nor do I know now.
Don't get me wrong... I feel for you and your situation.
Around here the building inspector checks footings and demands more excavation or a soils engineer if he does not find firm dirt at the bottom of the excavations.
I carry a probe rod in my truck, and check footings I have had dug (or dug myself). If what I find is not good I either get 'em to dig some more or call a soils engineer. The soils engineer usually just uses longer rods and an assortment of hand augers and few other fairly simple testers. He can tell by the way his tools go through the soil, and color and consistency of the soil be brings up with his auger, etc.
The probe rod I have is a ~ $25 tool that is simply a ~ 4' fiberglass rod ~ 1/2" in diameter with a thicker 'T' handle. The "business end" has a metal tip that is in a dull conical shape. Using it is not rocket science; I can teach anyone how to use it in 5 minutes or less, but it is the kind of thing that needs to be seen (felt) first hand and takes a little practice. I see a lot of probe rods made out of steel - the 2 disadvantages being that 1) it would probably get bent in the back of my truck with all the rest of the junk, and 2) if you happen to 'find' a wire you could have a shocking experience :-(
In your case, it might be something besides soft soils - like maybe expansive clay. Matt
I still think the engineer is responsible for his work. You are responsible for installing all of the materials to his specs. How could he claim that a foundation design was not site specific?? What other responsibility could you conceivably take?? I have a clause in my contract that states that I am not responsible for the work of design professionals. If I were in your shoes it would be my job right now to demonstrate that I had done what was drawn and spec'd. I would hopefully be able to do that using photos, building inspection approvals, field notes... and the biggie... inspections by the engineer himself.
I do think you should tell your client. It will not go away. It will not help you to conceal something you know about.... it'll make you seem complicit.
The six phases of construction:
1. Unrestrained enthusiasm and complete cooperation
2. The beginnings of concern
3. All-out panic
4. The search for the guilty
5. Punishment of the innocent
6. Rewards for the non-participants
Being my first complete house, I wanted and made a nice paper trail, but failed to call the engeneer before pouring. Plenty of pictures with tape measures in the dirt though.
I'll take your advice and alert the property owner. I now feel more at ease in doing so.
Step 3.5 :-- Fix the problem. (sometimes)
Sounds to me like the sub grade wasn't compacted properly to begin with. I know the states I've worked in so far require a compaction of 95% for most of this type work, although residential may not apply to these numbers.
In addition, my experience in this would indicate that the soil was not of a stable type, meaning crusher run or gravel, and the heaving was due in part to the moisture content of the soil rising and the material in question expanding, hence the heaving rather than dropping.
Clay is the main culprit in my experience, but there are other soils as well that could cause this condition.
If you've got a heaving problem now, it's gonna continue in the future..when the soil underneath dries it's going to settle and when the mositure content rises she's going to heave again, I know of no way to prevent this from happening, but I would certainly like to hear from others on how to prevent the situation from being ongoing....
If you aren't one of the one's I'm talking about,you shouldn't have any complaints....
The soil is clay.
The struct. engeneer told me that the design was drawn up without a soils report because the city didn't require one.
We had a ton of rain during the framing, when the crack started, and a three foot deep trench for an electrical duct on that side of the house wich caught most of the runoff.
I graded every thing away from the house,but I don't feel comfortable.
The property owner hired an architect who sub contracted the struct., elect.,and ect. engerring. I guess I need to find some one to read all the fine print. The owner isn't aware of the problem.
Tell the property owner now ,or wait for when/if the crack comes back?
Clay ... that's a very commoin soil in north Texas around Dallas ... and foundation repair companies have more ads in the yellow pages than the lawyers. The problem is that the clay expands ... a lot ... when wet and shrinks when dry. There are ways to deal with it, but that has to be done before the slab is poured. Chances are you're going tio have more problems in the coming months.
I'm sorry, I thought you wanted it done the right way.
Your structural engineer needs a few years practical experience in the field before he's allowed to use his stamp again. Just because the city doesn't require it doesn't mean it shouldn't have been done...seems pretty obvious this engineer doesn't have much experience or field time and sees everything on a 2 dimensional basis.
I don't know of any way to make the headaches disappear with your situation, maybe somebody out there with more experience than I've got can help you out.....If you aren't one of the one's I'm talking about,you shouldn't have any complaints....
Here is the reasons for cracking slab-
The clay soil was not flooded to fully expand the soil.
Post tension rods are required (by Engineers)for slabs with highly expansive soil (when dry the expansive soil has all sorts of cracks in it).
Steel rebar will crack the slab when it is too high up and heated by the sun.
Slab will crack if part of it is in the sun and other half in the shade.
It will crack where the first load stops and the next one started.
Also will crack where the pour is over an old slab stops and the dirt starts
Post tension rods?
I understand the rest.
If you hired the engineer to design a foundation for your specific site, then he/she is responsible for their design. However, not allowing he/she the opportunity to inspect the foundation before placement may be a problem. If the reply you got from him is accurate, you may want to complain to his licensing board.
I did rattle some cages. I'll let you know what happens.