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Deep Foundation Soils

Deep foundation soils are an important element of understanding soil stability. What should you know about deep foundation soils and systems?

Cut out view of soil layers with grass on the top

Deep Foundation Soils Can Require Foundation Repair

A deep foundation system may be something you need to install if you’re having issues with soil support in your foundation. Installing foundation support that reaches down into one of the deeper layers of soil might be an important element of your home’s foundation. However, it’s also important to know exactly what’s going on in the soil so you can understand why you might need a deep foundation system. Here’s everything you’ve ever wanted to know about deep foundation soils and systems.

Graphic representation of deep foundation soil layers

What Are the Layers of Soil?

It can be helpful to understand a bit more about the layers of soil when you’re starting to understand deep foundation soils. That way, you can understand exactly what you’re getting into when you start to consider a deep foundation support system

  • Organic Matter 

The top layer of soil is decomposed organic matter. This is actually underneath the layer of living organic matter. Sitting on top of the soil, you might find leaves, grass, and other materials, but as long as that organic matter is something you can personally identify, it’s actually not yet the top level of the soil.

Rather, this top layer of the soil occurs when the organic material decomposes entirely. It feels just like other types of soil, but it tends to be a bit more crumbly and dry. You’ll notice that the organic matter layer has very little structural integrity.

  • Surface Soil 

Underneath the layer of organic material, you’ll find surface soil, which some people will call topsoil or humus. It also utilizes organic materials, like leaves, grass, and branches, but these organic materials have completely broken down and become part of the dirt.

Surface soil is also where you find animals like earthworms and pot worms, as well as fungus and bacteria that thrive on plant roots. It tends to be dark, rich, and moist. In some areas, this might be enough to hold up a home, but it’s also possible for surface soil to have too much moisture and allow the home to settle too much.

  • Subsoil 

Once you dig past the surface soil, you’ll find subsoil. This doesn’t typically contain any organic materials at all. Rather, it’s where you’re more likely to find certain types of soil like clay and other expansive soils, typically hidden underneath the layers of surface soil.

This subsoil is typically not a great place to have your home’s foundation. However, because construction crews have to dig out a hole to set up a home’s foundation, it’s common for the foundation to press up against the subsoil layer. That can cause all sorts of problems for your foundation.

  • Parent Rock or Bedrock

The deepest layer of the soil is the parent rock, which some people may call the bedrock. It tends to contain large rocks and solid materials. In some instances, it may even be completely solid rock, although this is less common. Either way, it’s a very solid layer of soil.

When you have a deep foundation system, you’re typically going to be drilling the foundation all the way down to the parent rock or bedrock. That’s because this is one of the most stable layers of soil. If you’re not getting the structural support you need from the upper levels of the soil, you’ll probably get it from the bedrock.

Common Causes of Foundation Problems

Why Might I Need to Drill Down to the Deepest Level of Soil?

So what could cause you to need to install a deep foundation system? Deep foundation soils are a crucial part of the home for a number of reasons. These are just a few of the reasons you might decide to install a deep foundation system.

  • Not Enough Support in the Upper Levels 

The simplest reason you might need to drill down to a deeper soil level is just that you’re not getting enough support in the upper levels of the soil. For example, if you build your home without a deep foundation system, you’re probably relying largely on surface soil and subsoil to support the home, which might not work well.

Instead of relying on the surface soil and the subsoil, you can drill down much deeper and make sure you’re getting the maximum amount of support by gathering support from the lowest levels of the soil. Because bedrock has such a significant amount of support available, you can drill down and ensure your home has the support it needs.

  • Extremely Deep Upper Levels 

If you’re having issues with the support you get from the upper levels of the soil, you might want to look and see whether those upper levels are larger than they tend to be for other areas. If you’re seeing a lot of organic material and surface soil in a specific area underneath your soil, you might have even more issues with shifting and settling because these soils tend not to provide a lot of support.

However, a deep foundation system can help you push past these low-support soil levels. When you have a deep foundation system, you don’t have to worry about how extensive the upper levels of soil are. You can get right past them into the bedrock, even if it means you have to drill many feet into the soil.

  • Foundation Settling and Unevenness 

When you’re handling active issues with foundation settling, one of the things you want to think about is whether the home is likely to continue to settle. If you’re experiencing a very small amount of foundation settling in the first year or two after you build the home, it might stop. However, if it’s starting to sink farther as the home ages, it might continue to fall.

You need to make sure you’re not just keeping your foundation stable but actually lifting your foundation back to its initial position if possible. Because bedrock provides such a stable and extensive option for your home’s foundation, you can shift most of the home’s weight onto the bedrock layer with a deep foundation system.

FAQs About Deep Foundation Soils

Not every foundation will need a deep foundation system. This can be confusing for some people, who might not understand why their foundation needs a deep foundation when someone else’s doesn’t. The decision for whether your foundation should utilize a deep foundation system depends on a variety of factors.

  • Foundations With Enough Support

There are some foundations that get more than enough support from the surface soil and subsoil. This typically happens when the subsoil doesn’t have a lot of expansive soil mixes in it, the construction crew packed the soil properly, and the foundation is relatively close to the bedrock layer.

These foundations don’t usually need a deep foundation system. Most commonly, they already have enough support to manage on their own.

  • Foundations With Support Issues

The main reason that you might need a deep foundation system is if you’re having support issues all throughout your foundation. If you don’t have the support you need from the upper levels of the soil, you might be able to get that support from a deep foundation system.

Foundations with support issues definitely need that deep system. A deep foundation system is going to work best for foundations that already have an issue and need to fix that issue.

The depth of a foundation system depends on your unique situation. Your foundation system needs to go as deep as it has to go so it can hit the bedrock layer. That may only be a few feet, or it may be as much as 10 feet or more below the surface, depending on what you need.

  • The Soil Structure of Your Foundation System

Your foundation system’s depth should depend on the soil structure your foundation system is using. For example, if your foundation rests on a lot of very expansive soil, very poorly packed soil, or very wet soil, the foundation might not have enough stability to maintain itself.

When you’re seeing these problems, it may mean that the bedrock is further down than it would be for other homes. Additionally, some areas may see soil that is unevenly placed, with larger amounts of topsoil or other higher layers.

  • Getting Help From an Expert 

Figuring out the depth of your foundation system is not going to be simple. A foundation repair expert can help you figure out how far you need to drill to maximize your foundational stability.

Talk to a Groundworks expert to learn more about your options when it comes to choosing a foundation system, drilling the foundation system deep enough, and maintaining the foundation system.

There are actually many deep foundation systems you might be able to utilize as part of your foundation system structure. Finding the right deep foundation system is crucial if you want to make sure that your home’s foundation is as stable as possible.

  • The Different Deep Foundation Systems

There are many different deep foundation systems, all of which are best suited for different foundation situations. For example, you might be able to use helical piers, push piers, or another pier style, depending on your needs.

These different deep foundation systems all have different benefits and drawbacks, making them useful for different people. An expert can help you determine which one is right for your home.

  • How to Choose the Right System

Choosing the right deep foundation system typically requires that you understand the benefits and drawbacks of each. This is something a foundation repair expert can explain to you.

If you want to make sure you have the right deep foundation system, your first step should be to contact a foundation repair expert. They can help you understand which system will be perfect for your home.

The right deep foundation system for your needs will be different than the right deep foundation system for someone else’s needs. When you’re looking to decide on a deep foundation system, it’s a good idea to stay with the same person from start to finish, which means talking to an expert from the beginning of the process, if possible.

  • Choosing a System From Your Options 

Figuring out the right deep foundation system isn’t as obvious as it might seem because there are a number of variables you have to keep in mind. Sometimes, those variables might not even be obvious to you.

Choosing the right system is something that most laypeople can’t understand, so an expert’s help is not only useful but vital. It’s going to have a measurable impact on your home’s structural stability, after all.

  • Getting Help From an Expert

To adapt to all the variables and make sure you have the right deep foundation system, it’s important that you get help from a foundation repair expert. An expert will give you more insight into how a deep foundation system can help you and what it can do to benefit your home.

If you’re thinking about changing your foundation system and adding deep support, you need help from an expert. You can get more information from a Groundworks foundation repair expert.

Drill Deeper and Support Your Foundation With an Expert’s Help

Foundation support starts with an expert’s help. Your foundation is one of the most crucial parts of your home. If you mess up the foundation, chances are that you’re going to have to deal with a lot of problems before you’re able to get your home back into working order. This is why many people choose to leave these problems in the hands of capable experts.

Instead of doing your own thing and trying to DIY a foundation fix, you can trust Groundworks to provide you with the foundation fix that will work best for your unique problem. There are many foundation problems out there and just as many potential foundation fixes. A local expert will give you more information about your foundation, work with you to find the solution you like the most, and implement it into your foundation.

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