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Clay Soil

If your home was built on clay soil, don’t be surprised if you experience foundation problems. Here is everything you need to know about clay soil.

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How often do you think about the soil underneath your home? If your answer is “seldom,” do not worry, many other homeowners do not think about it a lot either. However, the soil beneath your home can greatly affect your foundation and impact your home’s structural stability. Unfortunately, most homeowners are concerned with the type of soil on their property only when they are landscaping.  

If your home sits on clay-based soil, you could experience some foundation issues. This type of soil is known for its poor draining properties and needs a lot of time to warm up. In addition, during warmer months it can dry out and crack. This is not good news for your plants or your foundation. 

Let’s take a closer look at the characteristics of clay soil, ways it can impact your foundation, and other important things about it. 

clay soil

What Is Clay Soil? 

A disintegrated sedimentary rock called humic shale creates clay soil. It is rich in various minerals such as zinc, calcium, and more. This fine-grained natural soil comes in various colors, shapes, and structures. This is why it is tricky to determine whether you have this type of soil in your yard.  

However, it has some properties that set it apart from other fine-grained soils. It is made from extremely small particles that are about 0.002 mm in diameter. In addition, when it encounters water it develops plasticity, a property that allows it to get deformed under a force and bounce back to its original shape when the force is removed. Unfortunately, this is not good news for foundation walls.  

Also, clay soil particles swell up when it rains and can hold a lot of water. This is why the foundation built on such soil can have a lot of problems. The ability to retain a lot of water is also a problem for plants in your yard since excess water can rot tender roots. 

How Common Is Clay Soil? 

Since clay soils are most common in the South, although they can be found all over the country, it is no wonder that a lot of homes in Alabama, Mississippi, Georgia, and Tennessee were built on this type of soil. Unfortunately, homeowners whose homes sit on expansive soils such as clay soil need to take extra measures to make their homes safe and stable. Due to heavy spring rains, the soil particles can easily swell up and then shrink during the summer, which can leave the foundation severely damaged. 

Clay Soil and Construction 

Clay soils are a real nightmare for builders. Constructing foundations, driveways, pools, slabs, or decks can be extremely difficult if clay soil is involved. Luckily, with proper preparation, it is possible to create a concrete slab without much hassle. For example, excavating clay soil and mixing it with gravel turns it into a stable base for the foundation. 

Clay Soil Movement 

As we’ve mentioned, clay soil is able to hold large volumes of water, and soil particles easily swell and expand, causing cracks in the foundation. On the other hand, during droughts soil can dry out and the particles will shrink once again, leaving gaps in the soil. Since the foundation will no longer be properly supported, it will settle into the hollow area where settlement has occurred. 

The volume of these shrink-expand movements depends on several factors, such as evaporation, compaction, and the presence of below-slab depressions. To minimize the volume of these movements, make sure that the soil in your yard is always moist. 

Clay Soil and the Foundation 

Due to the shifting of the soil, several problems can occur, such as cracks on foundation walls. When these cracks open, they leave the basement vulnerable to moisture. Over time, the foundation walls can bow as well. Since clay soil drains slowly, water can fill the gaps that are created between the soil and the foundation and accumulate behind retaining walls. This can lead to many problems, from rot to mold growth. While rot can compromise the stability of the structure, mold spores can contaminate the air in your home and cause all kinds of respiratory problems. 

Repairing the Damage 

Waterproofing or repairing homes that have been built on clay soils is not a job for everyone, especially because it requires special waterproofing and foundation repair solutions, skills, and experience. Therefore, instead of turning these repairs into a DIY project, it’s best to leave everything to the pros. This way you will be able to relax knowing that the job will be successfully completed.  

If you have noticed that something is wrong with your foundation and your home sits on poor supporting soil, contact contractors in your area and have them take a look. Here are some of the repair methods that can restore your home to its previous state. 

Foundation push piers – These galvanized steel piers extend far below the foundation and reach stable soils that can offer proper support. Depending on the level of damage your foundation has experienced, the contractors will determine the number of piers they will need to potentially lift your home back into its original position. 

Foundation helical piers – If you have a lighter structure, helical piers will get the job done. These are screwed into the ground and when in place, they will transfer the weight of the house to more stable soil. 

Drainage system – If your home is located on clay soil, it is important to prevent water from accumulating behind foundation walls. With an interior drainage system and a sump pump, your foundation will stay dry and moisture-free. Its purpose is to collect the water before it can cause any damage. 

Grading the soil – If every time the rain falls water runs toward your home and pools around it, your yard is not properly graded. This can lead to serious foundation problems, so regrade your yard as soon as possible. 

If you want to waterproof your basement or fix a damaged foundation, contact experts at AFS and schedule a free inspection and quote today. 

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