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Are Foundation Cracks Normal?: 5 Types to Look For

If the classic tune “As Time Goes By” was re-worked to address home damage, it might start like this: 

“Remember this homeowner hack, a crack is not just a crack…” 

Your home should not have foundation cracks. If you see a crack in the wall, it could be a sign of something more serious going on beneath the surface. 

Many homeowners are tempted to put fixing wall cracks on the back burner. Foundation cracks have become “normalized” because of underlying environmental factors homeowners are familiar with. 

Let this article be your guide to how to spot and handle foundation cracks. 

5 Common Types of Foundation Cracks 

Foundation cracks are common but in no way “normal” for homes to experience. 

Let’s explore the five most common types of foundation cracks you may notice around your home. 

1. Horizontal Cracks 

What They Look Like 

Horizontal cracks look like lines that run left to right or right to left. 

Where They Appear 

Typically, these cracks are on a basement or foundation wall. They usually form in the middle of the wall, appear to run parallel to the floor, and accompany inward wall bowing. As you can see, this crack near the top of the wall spans almost the wall’s entirety. 

What Causes Them 

These cracks result from hydrostatic pressure created by saturated, expanding clay soil. 

Soils rich in clay soil are often the most problematic soil because they expand and contract between periods of rain and drought, pushing against you foundation.

This continuous movement takes its toll on foundation walls, which will show signs of damage in the form of horizontal cracks and bowing. 

2. Vertical Cracks 

What They Look Like

These cracks are the opposite of horizontal cracks, as vertical cracks span up and down. 

Where They Appear

Vertical cracks can form along poured concrete basement walls and drywall, as well as exterior walls, like what is pictured here. 

What Causes Them

The soil is behind these cracks, as well, typically when the soil is dry. Where drought is more common (for instance, in places like Colorado), the soil shrinks as it is dries, inward pressure on your foundation. It almost pulls your house apart rather than pushing it in.

Shrunken soil cannot support your foundation and home, and it will start to settle into the ground. As the foundation moves downward, that’s when vertical cracking will become visible in basement and upper walls. 

Additionally, these cracks can appear if the foundation has heaved from underlying soil exposed to moisture and expansion. 

3. Stair-Step Cracks 

What They Look Like 

These cracks look exactly like they sound. They follow a pattern resembling stairs along a wall, and they can sometimes look like a March Madness bracket. 

Where They Appear 

Stair-step cracks typically form along the mortar joints in brick or concrete block walls. These cracks are more visible on exterior brick walls. 

Stair-step cracks usually start near a horizontal crack and spread up or down a wall. 

What Causes Them 

As with vertical cracks, settling soil and foundation settlement are the root of stair-step cracks. These cracks, in particular, indicate the foundation is settling unevenly. 

4. Diagonal Cracks 

What They Look Like 

Diagonal cracks show up at an angle on walls. 

Where They Appear 

They are most common in drywall and along the corners of door and window frames, like what is pictured here. 

What Causes Them 

An unevenly settling foundation resulting from unstable soil is also at the heart of these types of cracks. 

5. Slab Floor Cracks 

What They Look Like 

These cracks can be thin and spreading, or deep in the concrete. 

Where They Appear 

As the name implies, these cracks are found in your concrete slab floor, typically in the basement. 

What Causes Them 

It doesn’t take much moisture for volatile soil like bentonite clay to expand. When this happens, it heaves upwards and pushes against the concrete slab. 

This causes the slab floor to heave, bulge, and crack, typically in the middle. 

How to Repair Foundation Cracks 

When spotting a crack in the wall or floor, it’s common to want to slap a bandage on the problem with quick cosmetic fixes like caulk or other sealants. But these are temporary solutions that will not solve the problem. The cracks will only continue to worsen and accompany other damage

As we described above, the soil underneath and around your home is the main culprit, so it’s important to address this root cause. Professionally installed solutions that bypass or take the soil out of the equation include: 

These repairs will permanently stabilize your foundation and prevent any further movement. 

Contact Groundworks for Help Addressing Foundation Cracks 

Foundation cracks can be complex. What looks like a small floor or wall fissure at first glance might end up being a dangerous structural problem. 

Because of clay soil, prevalent throughout the US, it’s not a question of if the walls will crack, but when. Vigilance is crucial to repairing and protecting your home, and it’s important to be ready to quickly act. 

Groundworks is eager to be your partner in foundation repair. Our expert team has been helping homeowners across the United States address foundation cracks and other damage for more than 20 years. 

To get the process started, simply call us or complete our online form to book your free foundation inspection and no-obligation repair estimate. Together, we can help you create the safe and stable living environment you deserve. 

Call Groundworks for a Free Estimate!  

Foundation Cracks FAQs

Ignoring foundation cracks can lead to a multitude of problems that can become costly both in terms of money and health. 

The cracks can become larger and more extensive, jeopardizing the structural integrity of the entire foundation. Other risks include water infiltration, mold growth, and pest intrusion. 

All these issues can put your family’s safety in danger, as well as decrease the overall value of your home. 

If there is a hairline crack – also known as dormant or shrinkage cracks – in your foundation wall or concrete, it usually is harmless. These cracks typically form within the first two years after your house is built and it naturally settles into place. 

However, when you see significant cracking like large, spreading cracks, this is a bigger issue that needs to be addressed by foundation repair professionals. 

DIY fixes are not the answer. To get to the root of the problem, it’s important for repair professionals to inspect your foundation. 

Depending on where the cracks are, what they mean, and the extent of the damage, your house could benefit from a variety of solutions

For example, if your house is settling, helical piers will be used to stabilize and potentially lift it. For significant wall issues, repairs like wall anchors or beams can be used as reinforcements.