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Clay Bowl Effect

Due to the clay bowl effect, water soaks the soil around your foundation and exerts pressure on the foundation walls. Find out how to protect your home.

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Homeowners often forget that the foundation is the most important part of the house. It keeps your home stable and bears the load of the entire structure. Unfortunately, there are so many ways the health of the foundation can be compromised. One of the factors that can harm your foundation is the clay bowl effect. Although you may have not heard about it before, this effect happens a lot. 

When rain falls, the water finds its way through the loose soil around your home’s perimeter and to your basement. There it can cause problems with the foundation and infiltrate your basement. Although this can happen due to various reasons, the clay bowl effect is one of the most common. Let’s take a look at this concept and explain why it happens and how it affects your home. 

clay bowl effect

What Is the Clay Bowl Effect? 

During construction, soil is dug out to make room for the foundation. However, the hole is always bigger than the foundation, to give builders easy access. After the builders have laid the foundation and built the walls, they use the soil they previously excavated to fill in the gaps between the foundation and the earth. This soil that is returned to the ground is called the backfill. Since this soil has been moved around, it is no longer as dense as it was. Regardless of how hard the builders try to make it tightly packed once again, it will never be as it was. That is when the clay bowl effect takes the stage. It is a natural consequence of digging out the soils for the foundation. 

Since the backfill soil is more porous than the compressed, dense soil around it, it creates a” clay bowl” around your home. Every time rain falls or there is a flood, water will collect in this artificial water table. If you are not sure whether the clay bowl effect is causing problems with your foundation, you need to keep your eyes open for the elevated radon gas levels and cracks in your foundation, as well as persistent mold issues. Other signs that you are dealing with the clay bowl effect include dark patches on the basement walls and higher humidity levels in the basement than in the rest of your house. If the existing cracks in your foundation weep water, it is very likely that you have a “clay bowl” around your home. 

Should You Worry About the Clay Bowl Effect? 

The clay bowl effect should be taken seriously since it can lead to a wide range of problems. This effect can cause basement leaks, water damage, mold growth, and other issues. Anytime it rains, the snow melts, or the water pools around your home for some other reason, your home will suffer. The water will saturate the soil around your foundation, causing it to expand and press against your foundation walls. Due to this hydrostatic pressure, water will eventually break into your basement through the paths of least resistance such as cracks in the wall and openings around pipes. The water can also enter the basement through the porous concrete or the floor joint. Hydrostatic pressure can also weaken the joints in the foundation walls and widen the existing cracks.  

Another type of damage the clay bowl effect can cause is bowing foundation walls. Since the backfill soil is not as dense as it used to be, it moves freely, therefore exerting stress on your foundation walls. The constant variations in the pressure can cause the basement walls to bow and become far less stable. The clay bowl effect also leads to radon gas build-up in the basement. As the water soaks the soil beneath your home, it traps radon gas, which enters your home through the cracks. 

Possible Solutions 

As you can see, the clay bowl effect can lead to all kinds of problems and eventually even compromises the structural stability of the house. Luckily, there are several methods that can help you resolve this issue. 

Interior Drainage System 

The main problem with the clay bowl effect is that water can damage your foundation and enter your basement. With an interior drainage system that skilled contractors can install along the interior footer of your foundation, you can prevent water from causing trouble. The drainage system will collect the excess water and direct it to the sump pump, from where it will be pumped out of and away from your home.   

Wall Anchors 

Wall anchors prevent the walls from bowing any further and over time can even move them back toward their original position. They are constructed of galvanized steel and are the most effective method for even severely distressed basement walls. They are installed into the stable soil away from the foundation walls. 

Professional Foundation Waterproofing 

Another way to stop the outside water from seeping into your home is to waterproof the foundation. This way, you will prevent water from damaging your wooden support and ruining your belongings. Talk to your contractor about the best waterproofing solutions. 

AFS Foundation & Waterproofing Specialists offer various types of waterproofing solutions to homeowners in Alabama, Mississippi, Georgia, and Tennessee. Schedule a free inspection and our experts will provide you with a no-obligation quote. With AFS, you can find a lasting solution that completely suits your needs.

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