Heaving vs. Settling Concrete: What’s the Difference?

Heaving and settling concrete are two separate issues, caused by different external factors.

Whether the surface in question is your patio or your driveway, you need to get to the bottom of the issue to find a solution that lasts and prevents more damage.

Heaving and settling concrete

How can you tell if it’s heaving or settling concrete that’s causing dips, cracks and general all-around damage to your slab?

What Causes Settling?

Settling concrete is a common problem in slabs that were poured without proper soil compaction beforehand. If pockets of air are left in the ground under the structure, over time the weight of the concrete will cause them to dissipate, allowing the soil to sink. This creates a settling effect throughout the slab.

Recognize the Signs

Settling concrete is easy to recognize because the concrete sinks, giving it a concave appearance. Some sections may settle farther than others, but they don’t push upward.

What Causes Heaving?

Heaving is caused not by improper soil compaction, but poor soil composition. If the ground beneath the concrete has a high absorption rate, the soil will swell when saturated, then shrink during dry periods. Clay is a common soil type that exhibits these properties.

How to Tell the Difference

With heaving concrete, the middle of the slab often appears higher than the edges, since the surface is being pushed up by the expanding soil beneath.

While settling concrete typically only moves in one direction — downward — heaving concrete moves in both directions, according to the state of the soil below. Because of this, you might see many cracks along the edges of the slab, indicating the concrete has gone through this cycle more than once.

How Can Concrete Lifting Help?

Concrete lifting can correct settling through stabilizing the foundation beneath the slab. Working with a professional can also remedy heaving issues as well, as you’ll get in-depth guidance on limiting moisture saturation in the ground below your slab, and lifting techniques that can restore it to its proper position.

Get in Touch with a Professional

At Lift-Up Concrete, we take all slab damage seriously. Neither heaving nor settling concrete is too big a problem for us to tackle. With our years of experience, we know how to take a strategic approach and repair your surface as quickly as possible, producing long-lasting results. Call us today and share the details about your problem — we’ll provide a free quote.