What Is Differential Settlement?: A Cause of Foundation Damage

What Is Differential Settlement?

“Differential settlement” refers to a process of uneven structure settlement. The reasons can vary, but the most common is the unequal weight distribution of a building. This poor distribution will disrupt the foundation from bearing the load of the structure and allow it to sink into the ground, leading to severe structural damage. 

On the other hand, settlement can come from the soil too. If the soil begins to expand, contract, and eventually shift, it will cause the building to settle unevenly. Such behavior comes from a range of factors that include drought, floods, massive tree roots, run-down water lines, and even poor drainage. Still, it’s possible to see the warning signs before it’s too late. 

In case you find cracks in the concrete and the brick veneer, or your doors and windows aren’t working properly, you should suspect that you’re dealing with differential settlement. The cracks and fractures can allow moisture and pests to enter your lower-grade level. And on the other hand, your windows and doors that don’t work will affect temperature levels. Unfortunately, these are just small-time symptoms, and the main issue is even worse. 

Reasons Behind Differential Settlement 

As we’ve said, differential settlement doesn’t come out of the blue. Like other construction problems, it has its roots in the building process itself. And since the soil is a major factor, we’re going to look at two of its common types in Michigan and how they can affect your foundation. 

Expansive Clay 

The first example is expansive clay. In case you do more research about it, you’ll soon realize that it’s not exactly your best friend when it comes to construction. Depending on the weather conditions in your area, clay will either expand or shrink. Its properties are pretty similar to that of a sponge. 

When it comes in contact with water, clay will expand, and when there’s a drought, it will reduce in size. Experts also call it highly expansive soil, and the name speaks for itself. These physical attributes of clay will affect a home without a proper foundation beneath it. Moreover, they will make it settle. 

Bedrock/Load-Bearing Soil 

Opposite to clay, bedrock, or load-bearing strata as some call it, is one of the strongest supports for a foundation. However, its strength and durability don’t guarantee that you won’t have problems with differential settlement. To put it in construction terms, bedrock will interfere with the footing trenches, causing the structure to sink unevenly. 

Engineers have serious problems while constructing a building on rocky and hilly terrains. This is due to shallow and outcropping bedrock that will make one part of the home sit on soft and the other on hard soil. This is a recipe for disaster because the ground will provide uneven support to the structure above it. You can picture it like this: one part of the home will sink and the other on the hard rock will remain on its level. 

Other Causes 

Expansive and bedrock soil aren’t the only two factors that will contribute to differential settlement. Foundation problems are common if there’s massive excavation near your home. Likewise, if your soil is drying out, you can have this problem. But that’s not all. Differential settlement can come about due to the roots of big trees in your yard as well as if the dimensions of your foundation don’t match with the rest of your home.

Signs of Differential Settlement 

As we’ve said, this process is pretty unpredictable. It can happen during the construction, or it can pop up some time later. Nevertheless, you can spot signs and be proactive. And in case you do, it’s key to act immediately before you allow settlement to further damage your home. 

The first and obvious sign that there’s something wrong is if you see cracks on your foundation walls and the concrete slab. With time, these fractures will widen at the top and stay narrow at the bottom, warning you that you need to act. 

You can also realize that you’re having trouble with differential settlement if your doors and windows aren’t working properly. By this, we mean if they don’t open and close the way they should. Differential settlement will make them pop out of their frames, and they’ll no longer be on the level with one another. 

What You Can Do About It 

It’s important to say that you should keep an eye on the type of soil you’re building your home on. Being preventive will save you from various problems besides differential settlement and more importantly, costly repairs. But if you find yourself in a situation when it’s too late for that, you can employ foundation piers with professional help. 

Before you begin with the construction process, you should contact technicians who will thoroughly examine the soil on your lot. If they do it properly, you’ll be able to determine all the necessary physical characteristics that will allow you to install a perfect foundation. In case the soil isn’t good enough for the type of building you’re looking to erect, you can use deep foundations or replace the soil with some other type, making the ground in your yard stable enough for safe construction. 

If you’re having trouble with differential settlement, you can contact FSM for a free inspection and repair estimate. Afterward, you can choose from a range of options to repair your foundation and keep your home and family safe for years to come.

Differential Settlement FAQs

Is it safe to live in a house with foundation settlement?

Minor settlement is usually not a safety concern. However, significant or uneven settlement can lead to structural issues that may make it unsafe to live in the home until repairs are completed. 

Why does differential settlement happen? 

Factors such as soil erosion, drainage issues, poor soil compaction, fluctuating soil moisture, and nearby vegetation can contribute to differential settlement.

What’s the price range for foundation settlement repairs? 

Costs fluctuate based on damage severity and the chosen repair methods. Foundation Systems of Michigan offers free, no-obligation inspection and various financing alternatives to suit your budget. 

Leah Leitow

Content Writer

Leah is a Content Writer for Groundworks with nearly ten years of experience working in the foundation repair industry. Her experience ranges from working with homeowners to find the right solution to training inspectors and staff. In her background as a Michigan journalist, she gained invaluable insight into people's lives throughout our state. Leah lives in metro Detroit with her husband and two sons.

Related Resources

Why Drought Means Your Foundation is Settling

Are All Foundation Cracks a Serious Problem?

The Top 4 Foundation Repair Products in Michigan