Understanding Differential Settlement

A small brick house with a front porch appears tilted against a clear blue sky.

What Is Differential Settlement?

Differential settlement is the uneven or unequal settling or sinking of a home or building’s foundation. This occurs when the soil under your foundation contracts, expands, or shifts irregularly, causing the structure to settle unevenly.

When this occurs, the affected home or building develops small or large cracks and gaps in the concrete walls and floors. You may even notice problems that come with unevenness, like sticking, with your doors and windows.

Signs of Differential Settlement

Whether settlement happens in a few months of owning your home or takes a couple of years, the problems that arise remain pretty much the same. You’re likely to experience multiple issues such as:

Sticking doors and windows

Wall and floor damage

Lower vertical crack on the window wall.

Drywall Cracks

Large crack in concrete close up with tape measure

Foundation cracks and deterioration of slabs

Bowing and cracked brick on the exterior foundation wall.

Structural instability that makes your building unsafe

Understanding you have a problem is the first step, but foundation problems don’t get better on their own and need professional repairs to stabilize your home and protect your family.

What Causes Differential Settlement?

Shrinking and dry, cracked soil. — The soil under your home can affect the stability of your foundation.

Cracked and dry soil. — The soil under your home can affect the stability of your foundation.

Let’s look at some of the reasons that might cause your home’s foundation to sink unevenly.

Weak Soils

Highly compressible soils have a weak bearing capacity. Structures erected on such grounds require special footings to help spread the load of the building over a wider area. This will help prevent differential settlement.

Poorly Compacted Soils

During the construction of a building, the ground may require artificial leveling and filling to ease the construction process. When adequately compacted, this fill soil provides a substantial base for supporting the foundation. If not properly packed, the ground may settle unevenly under the building’s weight, leading to structural damage.

Expansive Clay

Clay soil is one of the worst soil types for building. This is mainly because this soil swells with water during wet seasons and shrinks during the dry months. Soil that behaves this way is highly expansive.

If your foundation sits on clay soil, you are likely to experience differential settlement after some time. Your footing will settle downwards during the dry seasons as the clay shrinks.

Bedrock Issues

The bedrock is one of the strongest supports a foundation can have. This, however, does not mean that it is immune to differential settlement. Sometimes, the bedrock may intercept the footing trenches, causing differential settlement. Hilly and rocky areas tend to have shallow and outcropped bedrocks. Builders find it hard to dig through such soil to cast trench footing.

Restoring a Settling Foundation

Your sinking foundation needs to be underpinned using piers and there are a few ways to do this. While the specifics may vary, the general concept is the same, transfer the heavy load of your home to the deep stable bedrock and stabilize the foundation.

Helical Piers for Foundation Repair

Also known as screw piles, helical piers consist of a central shaft with several helix-shaped plates. These piers are versatile and great for supporting light structures such as porches.

Push Piers

Mechanically driven into the earth, push piers help pass your structure’s weight to the stable bedrock. They’re installed close to the footings and secured in place using brackets. These systems are easy to install and cause little disturbance to the landscape.

Differential Settlement Prevention

When it comes to foundation issues, prevention is the first step. Builders should start by assessing the soil to confirm that it is perfect for the type of structure they want to put up. Ideally, you should build a house on soil layers with minimal clay or silt. This way, you will not have to worry about the soil under your foundation shrinking and expanding. If possible, the house should sit on native soil and not fill soil.

Before any construction work starts, get a professional to determine the load-bearing capacity of the soil. They will advise you on whether the ground needs some improvements or amendments early enough and whether a deep foundation is necessary.

Groundworks Puts Homes Back on Solid Ground

If you’re noticing signs of differential settlement around your home, it’s important to choose a company with a proven track record of repair. While this might sound obvious, the risk of choosing a plumber to install your garbage disposal and someone to stabilize your sinking home is drastically different. You want a company with engineered products tested throughout the country in all types of soils, an installation team with world-class training, and a company that will be around for years to come.

In the last 12 months alone, Groundworks has stabilized more than 17,000 homes across the country. All our products come with a nationally backed warranty. Meaning if your home ever needs an adjustment, we’ll be here when you need us.

The local experts in your area understand the unique soil and climate issues your home is facing and have years of experience repairing problems like yours. Read thousands of reviews online and rest assured you’re making the right decision.

If you have any foundation concerns, contact us today to schedule a free foundation inspection from your local expert for a lasting fix to your foundation settlement problem.