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Soil under my foundation

Is Damp Clay Soil Something to Worry About?

Expansive soils like clay can cause a great deal of damage in many homes. Here’s what you need to know about these soils and how to protect your home and foundation.

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It’s hard to quantify the impact of damp clay soils around the country, let alone Baltimore, MD. Nearly 25% of homes experience structural damage or cracks due to soils with superior absorptive ability. With this hindsight, it’s important that you learn how clay soil affects your home and what you can do to minimize its impact. 

Damp clay soil is bad news for any homeowner. If you don’t act now, you could be staring at serious foundation problems that could jeopardize your home’s structural integrity. 

soil under my foundation

Coming across damp clay soil is conflictive for any homeowner. It could mean significant foundation problems that could jeopardize your home’s structural integrity. 

Learning About Damp Clay 

As the name suggests, damp clay is soil that has a high moisture content. The water could be from excess rainfall, snowmelt, or burst pipes near the foundation. This soil swells and expands in the presence of moisture. 

While their particles are tiny, clay soils can absorb water with tremendous efficiency and expand several times their original size. 

Clay can get wet or damp during heavy rains or because of poor drainage. Rains will saturate the soil with water and soften it. The same thing may play out if the drainage is poor, as water will collect around the foundation. 

Leaking water lines, sewer lines, underground streams, and high water tables might also contribute to the wetness. We encourage you to perform checks once a year, both inside and out, to determine the condition of the foundation. 

Symptoms of Damp Clay Soils 

Summer and spring are particularly hard for your home as the soil’s conditions change drastically. Your foundation is likely to experience settlement and cracks during either season. Other telltale problem signs that should prompt you to take action include: 

  • Gaps and spaces around your doors 
  • Cracks on brick veneers 
  • Sagging or bouncy floors 
  • Self-closing or opening doors 
  • Doors and windows that stick to their frames 
  • Soil pulling back in summer 

Should I Worry about Damp Clay? 

Clay soils that sit in the active zone, an area that’s affected by water or climate change, are likely to expand and contract depending on the soil moisture conditions. During the wet season, the soil expands and exerts pressure on your foundation walls (hydrostatic pressure), potentially causing them to crack or bow inward, which reduces their stability. 

Drought conditions will just be as bad. The drying clay will shrink and form gaps that won’t bear the weight of your home. Within no time, the foundation can settle where gaps exist. Floors may be out of level, cracks can appear on the walls, and windows and doors will start sticking. 

Clay and water have a stronger interaction than other soils due to the large surface area of their particles and the structure of the minerals that exist in the soil. Often, these minerals do influence soil movement and behavior. 

When the soil swells, it loses its ability to bear the weight of your home. Swelling foundation soil may exert an upward force that can displace the foundation by up to eight inches. This can cause floors to become uneven. 

Ways to Mitigate the Effect of Clay Soil 

Moisture is behind the many cases of foundation damage we’ve handled over the years. Most of your efforts should be directed toward controlling it. You can’t remove wet clay soil beneath the foundation. The most sensible thing to do is try to minimize its impact on your home. 

Here are several ways to manage this problem. 

  • Implement positive site drainage around your home to discourage water ponding. 
  • Use drip irrigation to water your plants and trees so as to reduce the amount of water that saturates the soil. 
  • Keep trees and shrubbery at least 10 feet from your house as they tend to absorb water and dry out the soil. 
  • Install and maintain gutters and downspouts to ensure water gets deposited far away from your home. 
  • Ensure the landscape and soil around your home, especially the yard, has positive grading and slopes away so water flows naturally. 
  • Compact the backfill around the foundation to avert the clay bowl effect. 
  • Use sprinklers with timers to prevent overwatering the yard. 
  • When building a new home, erect a sturdy foundation wall that can withstand various damaging factors. 

Professional Foundation Repairs 

Whether you are noticing damp clay soil for the first time or have struggled with foundation issues due to wet clay soils, JES Foundation Repair can help you with your unique situation. Our foundation repair experts will visit your home for a thorough inspection, and then fill you in on the next steps. To get started, contact us today to schedule a free foundation inspection and repair quote

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