foundation / settling problem

[thedigitalguru]

Good morning all - I've tried to do my homework before asking, but cannot find any good source of info regarding midwest clays, soil expansion, and poured basement foundation cracking. We purchased our home one month ago (located in Kansas City, MO) and within one week of possession found settlement problems with the back living room extension of the house due to clay compaction and the drying of an underground spring due to the summer's dry weather. This was compounded by the previous owners not watering the foundation during the hottest periods. The house is a 2000sqft split/tri-level house with an unfinished poured concrete basement / foundation.

I _do_ plan to hire the work of an engineer to oversee the repairs, but have a quick question. After getting out the laser, it appears that the rear-corner of the foundation has dropped approximately 3/8-1/2". In the interim, I have set up a semi-buried perimeter drip-system 4 feet from the foundation and timed sprinklers in the yard to try and establish some moisture content in the soil.

I have also made and affixed acrylic 'gap rulers' on each side of the cracks to monitor any further movement (which appears to be only parallel to the basement walls - no inward/outward expansion).

My question: With the daily watering regiment, do you believe it's possible to have any positive correction in the cracks with clay expansion as the moisture content of the soil increases? I understand this is not a permanent correction, but just a temporary stabilization to get us through the winter.

Thanks for any insight/experience you can provide.

[Glenn]

You may be going about this backwards. I am in KC too actually JC.

I had a job once where the house went down on one end eight inches. The dirt has shrunk away from the house, the grade was toward the house and water poured down the wall. Turned out that just below the good clay (and clay is good for a foundation. All houses in the KC area not on a rock ledge are on clay), there was a layer of white clay which when dry is like concrete and when wet, like quicksand.

Your problem may well be too much water in the wrong place. Is your exterier grade the 6" fall in the first 5' this area calls for in the local code? (or 5" in 6', can never remember which)

I heard one so called expert on a talk radio tell people to take a hose and lay it to run into the crack between the foundation and dirt to soak it up. So much for "experts".

[Italian Mason]

This was compounded

Hmmmm....... watering the foundation hu?.......thats a new one to me. Id like to here more on this practice...

extension of the house due to clay compaction and the drying of an

How do you know this information? Did you have a soil test done? If not Id get one done like NOW before trying anymore homemde fixes, you may be adding to the problem. If your putting water on this thing daily and you could very eaisly be creating voids in the soil undermining what you already have.....the water has to go some where and it is probably taking soil with it..

[e-mail] wrote:

[Pete C.]

Very common in areas with expansive clay soils. There idea is to keep the clay soil at a consistent hydration level which translates to a consistent expansion level and avoids the cycling of expansion due to varying hydration. This cycling is what causes the compaction and loss of contact with and support to the foundation, resulting in the settling and cracking issues.

Regions of the country that don't have expansive clay soils have never heard of this of course.

Pete C.

[Eric in North TX]

Seldom do I defer to the experts, but in this case, find a reputable foundation leveling company and hand it to them. Do as another poster suggested and improve your drainage / grading to avoid another expensive visit.

[frippletoot]

Watering the foundation can also be used as a BS excuse by incompetent home builders, to delay the homeowner filing complaints long enough that the builder can say the warranty and/or statute of limitations ran out. I've lived in several states and many areas of the country have "expansive clay soils." One really good example is the desert southwest, where there is clay, plus extremes of wet and dry weather. You might get most of your year's typical rainfall within a few weeks. If a foundation is built right, on a site that's prepared right, you should not have to "water your foundation."

E.g. desert landscaping which is required in some areas now due to water shortages: you cannot water the house in any practical manner and could be fined for trying to do so. A good foundation is not a delicate flower requiring hothouse care. A good foundation is built to withstand the soil and the weather for that region. The fact that so many new homes have foundation failure has much more to do with builders taking shortcuts or not knowing what they are doing. A shame the industry spends money on lawyers and spin doctors to think up BS like watering your foundation instead of doing the foundation right.

That said, if you have foundation problems what you need is a structural engineer and/or a soils engineer. There may be a need for drilling deep core samples. If you do this get a core of your foundation as well as the soil in a few places. Sometimes a lot can be learned from the concrete. Ideally, all building sites would have a soils and engineering report. Sometimes this is required but I feel that it's not required enough, or is not enforced. You might want to try and find out if your area does require it and where you'd get a copy of the report. Sometimes the reports are just "recommendations," meaning the builder was under no legal requirement to follow it, but it can still support your position by showing that the builder didn't follow recommendations for the site. Certainly underground water, if that's the case, would be a big mistake to build over without a lot of precautions at the very least.

Italian Mas> This was compounded

[nowforsale]

everything on thise site is relevant

at it as numerous zones around your house, and of some are watered too much and some not enough, foundation probelms ensue, how you monitor and how you water the zones determines your cost for remediation then control