Why Is My Driveway Uneven In The First Place?

Jun 15, 2026

Jamie Unruh

You’ve parked your car on your driveway after a day at work. You get out, grab your bag, and walk toward the door, tripping on the way. Whoa! What?! You immediately look back at what you fell over and realize the concrete slab of the walkway alongside the driveway has dropped.

That wasn’t there yesterday. Was it? Itlooks like one side of the slab has sunk or settled into the ground.

This is just one common scenario that some homeowners face. There are many different ways that concrete around a home can be affected.

There are typically five things that can cause concrete to settle in the Calgary and Central Alberta area: soil behaviour, weather, downspouts, backfill and utility lines.

Let’s take a closer look at each one.

Soil Behavior

Before concrete is poured, the dirt in the area needs to be pressed flat in order for the concrete to set properly.

Compacting the ground is basically squishing the dirt to reduce the amount of space between the soil particles. This is what helps prevent concrete settling which causes concrete to crack or become uneven.

When compacting the ground, the type of soil will determine how it behaves to the compacting.

Coarse grained soil, like sand or gravel, is ideal for concrete work as it has high permeability (ability to allow water to pass through it).

Then, there’s fine grained soil which is silted or clay-like. This type of soil absorbs water which will expand and contract with the seasons.

Dirt in the Calgary area tends to consist mostly of clay so this shrink and swell movement over time can cause unstable soil and eventually cause a void under concrete. This void diminishes the support for a concrete slab in turn, causing the slab to settle and become uneven.

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Weather

Living in the Great White North has its perks. We’ve got wonderful, hot summers, but then we can have harsh, cold winters.

The constant cyclical freeze thaw cycles, amplified by chinooks, will cause repeated expansion and contraction of the soil beneath all year long.

While the water soaked clay we talked about above causes a similar reaction, the high moisture content in the soil will also shrink and swell causing unstable soil and concrete settling.

Downspouts

Poor water drainage on a property is another reason concrete can settle. Downspouts attached to a home are not always placed in the appropriate place which can create a pool of excess water in turn compromising a concrete slab foundation or even your home’s foundation. And that’s just plain bad news.

Downspouts located too close to a sidewalk, driveway or patio will quickly erode the subsoil close to the foundation. This area is generally weaker anyway because of the backfill, so the constant flow of water will cause voids which again, makes the concrete slab unstable and start settling.

If, say, a patio close to your house isn’t well sheltered or water isn’t draining far enough away, the soil under the patio will move eventually eroding the dirt close to the home’s foundation wall.

In addition, if the concrete patio settles, creating a negative angle towards the house that was originally designed to shed water away from the house, then the home foundation is going to be negatively affected.

Then, once rainwater and snow start to melt on the patio, it’s flowing toward the house foundation and compounding the problem.

No one wants their house in jeopardy like that, but home inspectors see it often, so if you see concrete in and around your home settling, call a professional to fix the issue before it becomes a bigger problem.

Backfill and Poor Compaction

Earlier we covered compaction of differenttypes of soil prior to pouring concrete. Poorly done compaction no matter whattype of soil is used, ends up having the same effect.

Concrete settling is especially common innewer neighborhoods because the backfill isn’t always compacted properly oruniformly.

Before foundations of new homes are poured, the area is usually excavated quite deep, anywhere from four to eight feet deep, and after the foundation is set, the backfill is pushed back in. That’s a lot of dirt to press back to a solid-ish state, so if that backfill isn’t compacted well enough, or if it contains inconsistent fill, the concrete will continue settling under the weight of normal traffic.

The settling will typically appear in lower spots such as along the garage apron where it meets the driveway, sidewalks, along the side of the house and patios, usually in the first few years of the home being built.

Utility Lines

When a utility needs to be laid in or repaired, it often means a trench needs to be dug or cut and that can often lead to poor compaction issues too.

Of course, utility workers will do their best to leave the area as they found it, right?

.... Well, in most cases we hope they do.

Whether water, electrical, gas or communications lines, sometimes when backfilling the soil, workers will be careful to not damage whatever line they’ve just installed, so they might not always compact the area as it’s needed to prevent concrete settling.

Directional drilling to access some utilities has been known to cause concrete settling. Unfortunately, we do get several calls at Beyond after such a situation

Multiple Concrete Concerns

When concrete is settling, it’s not always just one thing that’s causing it, settling can oftentimes, be due to an overlap of any of these issues. If one problem (cracking, shifting, and/or settling) is occurring, it will likely lead to another and cause one big headache.

In instances where there’s no obvious cause of the concrete settling, we start by asking a lot of questions and occasionally we might ask an engineer for help with reasonings we can’t figure out. At Beyond, we’re a "fix-the-problem-and-the-cause-of-it" type of company, because, honestly, we don’t really want to see you again. Ha! Jokes aside, if multiple things are happening in the same area, it’s a good time to give us a call.

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