5 Types of Foundation Cracks and What They Mean for Your Home

Seeing cracks in your home’s foundation can understandably cause some worry. Foundation cracks can range from harmless to serious; knowing the difference is important. While some cracks are simply cosmetic, others can indicate bigger structural issues that need immediate attention. So, how can you tell what’s going on beneath your home?

This article will cover the top five types of foundation cracks, what they mean, and when it’s time to call in foundation crack repair specialists or consider professional basement waterproofing services.

1. Vertical Cracks

Vertical cracks are some of the most common foundation cracks homeowners see. These cracks typically run straight up and down or at a slight angle (within 30 degrees). Vertical cracks are often caused by the natural settling of your home over time or by concrete shrinkage as it cures.

Are they Serious?

The good news is that vertical cracks are usually not structural. They’re more cosmetic, especially if they are thin (less than 1/8 inch wide). However, they can let water seep into your basement, leading to dampness, mold, or even flooding during heavy rain.

What to Do About It

If you spot vertical cracks, don’t ignore them. Over time, even small cracks can widen and let in moisture. Calling professional basement waterproofing services to seal the cracks and install waterproofing systems helps prevent water damage before it escalates.

2. Diagonal Cracks

Diagonal cracks run at a slant, often starting at the corners of windows, doors, or foundation walls. They are more concerning than vertical ones because they are usually caused by uneven settling or pressure on the foundation from shifting soil.

What Causes Diagonal Cracks?

Soil movement, erosion, or changes in moisture levels around your home can cause one part of your foundation to settle more than another. This uneven pressure causes diagonal cracks to form.

Are They Serious?

Diagonal cracks can be both structural and non-structural, depending on their size. Thin cracks may not be a huge issue, but wider cracks (more than 1/8 inch) should be evaluated. If you notice diagonal cracks growing over time, it’s time to call foundation crack repair specialists for an inspection.

What to Do About It

Repairing diagonal cracks involves sealing them to prevent water infiltration and stabilizing the foundation to prevent further movement. This may also include addressing soil issues around your home to reduce pressure on the foundation.

3. Horizontal Cracks

Horizontal cracks are among the most serious foundation cracks a homeowner can encounter. These cracks usually run parallel to the ground and are a clear sign of structural stress.

What Causes Horizontal Cracks?

Horizontal cracks typically form when water pressure builds up in the soil surrounding your foundation. This pressure, known as hydrostatic pressure, pushes against the walls and can cause them to bow or crack.

Are They Serious?

Yes. Horizontal cracks indicate that your foundation is under significant stress and may fail. If left untreated, the walls can eventually collapse, leading to serious and expensive damage.

What to Do About It

Horizontal cracks require immediate attention. Repair methods may include reinforcing the walls with steel beams, carbon fiber straps, or even rebuilding sections of the foundation if necessary.

4. Stair-Step Cracks

Stair-step cracks are often seen in homes with brick or concrete block foundations. These cracks follow the mortar joints, creating a staircase-like pattern.

What Causes Stair-Step Cracks?

These cracks are usually caused by uneven foundation settling or soil movement. Like diagonal cracks, they occur when one part of the foundation shifts more than another.

Are They Serious?

Stair-step cracks can range from minor to serious, depending on their size and progression. The cracks may not require immediate repairs if they are thin and stable. However, wider cracks or cracks that grow over time could indicate structural problems.

What to Do About It

If you see stair-step cracks, it’s best to have them evaluated by a specialist. Repairing stair-step cracks often involves stabilizing the foundation, sealing the cracks, and addressing soil or water issues around your home.

5. Hairline Cracks

Hairline cracks are thin, superficial cracks that often appear in newly poured concrete as it cures. These cracks are usually very fine and may not extend through the entire foundation wall.

Are They Serious?

In most cases, hairline cracks are harmless and purely cosmetic. However, they can still let in moisture over time, especially if you live in an area with heavy rainfall or fluctuating temperatures.

What to Do About It

While hairline cracks may not seem like a big deal, sealing them early can prevent water from entering your basement.