Want to know why concrete sinks?
IT’S ALL ABOUT THE DIRT!
Concrete sinks when the soil beneath the slab washes out or compacts. There are many reasons why the soil fails around your home. In Central New York, most of the time soil is sandy or clay. Here are the three 3 major causes of soil problems. First drying and shrinking of the soils. The second wetting and softening of soil and last is poorly compacted fill soil.
1 - DRYING AND SHRINKING SOILS
During prolonged dry periods, the soil around your home dries. This is especially true with clay soils. The dry shrinks the clay soil creating a void. When this happens, to concrete this could cause sinking or major cracks. When soil shrinks around foundations this can lead to structural damage.
2 - OVER-SATURATED SOILS
Water can be dangerous for your home’s structure in many ways. Here are some common causes of water over-saturation:
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Heavy rains can cause dry soil to become over-saturated. Now, this over-saturated soil can cause heavy objects to sink. For example your slab of concrete or even your home.
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Another way rain can cause damage is poor drainage. From clogged gutters to hidden areas of water. These areas can cause water to pool next to the home, which softens the soil. This small bit of water can cause big problems for your concrete or home.
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Plumbing leaks and broken water lines under or near a home can be really detrimental to the soil. This water could be one of the biggest problems because it's hard to diagnose. Water from plumbing problems can cause slabs to sink, or even the whole foundation. Another problem with plumbing leaks is their location under the home. These types of leaks can wash soils out from under the home, creating a void beneath the structure.
3 - POORLY COMPACTED FILL SOILS
Homebuilders sometimes use quick fixes that can cause long term problems. The builders will bring in soil from other areas to level the lot. This “fill soil” is typically looser than the hard-packed soil. This fill soil is usually compacted before placing a foundation. But, if this compaction is not done, your home’s weight may cause the soil to compress. The compression can lead to foundation settlement issues or concrete breaking.
Homes built on hills are one area where we see big problems. If your house is on a slope, chances are that half your house is sitting on the original soils and the other half is on fill-soils.
So now you know, the concrete settlement is definitely all about the dirt!
