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Clay Bowl Effect

The clay bowl effect contributes to flooded basements and crawl spaces. Here, we cover what causes this effect and how you can prevent it.

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Flooded basement with crack in the floor

What Causes the Clay Bowl Effect?

When the foundation of a house is built, the construction workers need to excavate the soil to create a hole that is larger than the actual basement itself will be. This allows them to accurately measure and build the floor and walls of both the foundation and basement itself. 
The gap surrounding the newly constructed basement is then backfilled with a portion of the previously excavated soil. The clay bowl effect is a natural consequence of this foundation construction. The backfilled soil compacted around your foundation forms a sort of empty “bowl” around it. The clay bowl effect occurs when water mixes with that “bowl” of soil to press against the foundation. Severe storms may even wash away parts of the “bowl” entirely.
As a result, the foundation may shift or crack over time. This is just one example of the clay bowl effect in action. Let’s find out more about the clay bowl effect and what causes it to happen in the first place. 

What are some problem signs you should look out for?

This effect can occur with any home, regardless of if you have a basement or not. The way foundations as a whole are constructed is why this effect is so detrimental to basements. The bowl shape the soil creates can cause plenty of issues later on.

  • Leaky Pipes

Discovering seemingly random pools of water along your floor usually indicates that your pipes are leaking. It could be your pipes are simply misaligned and you need to hire an expert to straighten them out again.

Leaking problems may also indicate that the clay bowl effect is starting to affect your home’s foundation. These leaks should not be ignored. Collecting the dripping water in buckets to empty out later is not a solution, especially if a huge storm hits your area. 

  • Cracks

Cracks creeping along your basement’s walls or floor are often signs of a larger foundation problem. Even the smallest hairline cracks might be a sign of the clay bowl effect taking place. Left untreated, the cracks can expand further to cause serious issues to the infrastructure of your home. Cracks of any size can also contribute to severe flooding in your basement.

  • Flooded Basement

This is perhaps the most obvious issue the clay bowl effect presents. Your foundation is specifically built to keep your home upright and dry. If your basement is uneven and consistently floods every time it rains, you will know something is wrong.

Clay Bowl Effect Causes

The clay bowl effect itself can cause massive damage to your basement and foundation. However, the effect itself can be triggered by different factors. So what causes the clay bowl effect in the first place? 

  • Hydrostatic Pressure

The backfilled soil surrounding your foundation is often looser than the soil directly underneath the foundation itself. Most of the time, this backfill will never become firm again. This makes this soil more porous, allowing it to soak in more water during storms or heavy snowfall. The water cannot seep through to the much harder soil underneath the foundation, so it settles into the backfill around it.

The soil thus becomes far more saturated with water than it can handle. This is made all the worse if you do not have efficient gutters or downspout systems in place to drain it away. The combined pressure from the backfilled soil and the water can alter the leveling of the foundation. It may even cause it to crack.

If there is enough of a downpour, the excess water and soil may then start to trickle into any tiny fissures, holes, and pores left in the concrete foundation. Over time, this may cause the foundation to fracture or shift from its original position. Any moisture still caught in these pores during the winter is likely to freeze, expand into ice, and crack the foundation even further.

Especially severe storms can be problematic. After thoroughly wrecking your foundation, the water may continue to push through to your basement or crawl space. This can lead to larger problems such as: 

  • Flooding
  • Electrical issues
  • Wood rot
  • Musty smell
  • Mold growth
  • Attraction of pests
  • Ruined belongings
  • Old or Uneven Foundation

Over time, your foundation will start to show signs of wear. Continuous hydrostatic pressure creating leaks and cracks and moisture infiltrating its concrete pores can wear it down pretty fast.

All this damage can cause your foundation to become uneven. Most homeowners do not have the tools or the experience to fix something this essential to their homes. Often, an uneven foundation can remain undetected for years until the problems get out of hand.

Recreating a stable “clay bowl” and foundation requires an expert’s help. If you are experiencing any flooding or foundation issues, hire an inspector to look at your basement. They will be able to properly assess any problems and help you come up with solutions to patch up your basement.

How to Prevent the Clay Bowl Effect

Knowing what causes the clay bowl effect is the first step toward flood prevention. After an expert assesses where the issue truly lies, you need to determine what waterproofing method is best for your home. How can you prevent the clay bowl effect from damaging your foundation? 

  • Install a Better Drainage System

Most homes already have drainage systems installed within their basements. However, if they cannot steer the water away, then they are clearly not functioning properly.

This is when you need to get a better drainage system. This system can either be an interior or an exterior outlet. An interior drainage system like the AquaStop BasementGutter™ system redirects the water to a sump pump and away from your basement. Usually, the water is expelled into a storm drain or other drainage point. Rather than direct the water to a far-off drainage point, an exterior drainage outlet will disperse this water out onto your lawn instead.

Both systems have their pros and cons. Some will fit different types of homes better than the other. You must let an expert assess which type is best for your basement. 

  • Foundation Repair

The hydrostatic pressure caused by the washed-out soil might shift or crack your foundation. The foundation of your home is meant to keep moisture out at all times.

If you are experiencing foundational issues, it is best to call an expert to repair your damaged foundation. This will not only prevent the clay bowl effect from further ruining your foundation, but it will also help keep water out of your basement permanently.

Hiring the Experts

Flooded basements and uneven foundations can be a pain for any homeowner. All that water damage to your property can start to add up and cost you thousands of dollars.

Yearly inspections and hiring the right basement repair experts can prevent these costly issues from occurring at all. The clay bowl effect may not be entirely preventable, but flooded basements and crawl spaces can be!

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