The Best Way To Fix Cracks In Concrete Foundation Walls
You’ve spotted a crack (or maybe a few) in your concrete foundation wall. Naturally, you’re feeling a bit concerned and tempted to grab the caulk and seal it up yourself. But is that really the best approach?
You’re not alone—many homeowners face this issue, and it’s normal to feel uneasy about what these cracks mean (and how much it might cost to fix them). Whether you’re seeing hairline cracks or wider gaps, it’s crucial to address them early to avoid bigger problems down the road.
In this article, we’ll break down why these cracks occur, why DIY repairs aren’t always the best choice, how to fix them, and what steps you should take to protect your home’s foundation. Let's get into it.
Why do foundation cracks happen?
If you’re seeing cracks in your concrete foundation wall, you might be wondering what’s causing them. Foundation cracks can happen for a few reasons. Here are some of the most common:
Your home rests on soil that, when saturated, puts pressure on all sides of your foundation.
1. Soil movement
Over time, the soil surrounding your home can shift for a few reasons. Weather changes, water saturation, and even poor soil compaction can cause the ground to move.
When the soil shifts, it creates pressure against the foundation, which can lead to cracking. There are two types of soil movement that often come into play:
- Expansive soils. Certain types of clay-rich soil expand when they absorb water and shrink when they dry out. This constant expansion and contraction can push against your foundation, causing stress and eventually cracks.
- Erosion. Heavy rain or bad drainage can wash away soil beneath your foundation, causing it to settle unevenly. This type of soil movement can result in cracks as the foundation tries to adjust to the new, uneven ground.
2. Hydrostatic pressure
When water accumulates around your foundation—either from heavy rains, poor drainage, or high groundwater levels—it can create what's called hydrostatic pressure. This pressure pushes against the foundation walls from the outside.
When the pressure becomes too great for the wall to bear, it can cause horizontal or diagonal cracks. Without proper drainage solutions, this pressure can worsen over time, leading to more significant structural issues.
3. Foundation settlement
All homes settle into the ground to some degree as time passes.
Uneven foundation settlement causes part of your home to sink while the other remains in place, leading to wall cracks.
This natural settling process occurs as the soil beneath your home compresses under the weight of the structure. But if the settlement is uneven or excessive, it can lead to vertical or stair-step cracks in your foundation walls.
This can happen for a few reasons. Here are the most common.
- Improper soil preparation during construction, which results in a weaker base for the foundation.
- Changes in moisture levels, such as prolonged drought or excessive watering near the foundation, which can cause soil to contract or expand.
- Tree roots seeking water sources beneath the foundation can also disturb the soil and create settlement issues.
4. Poor drainage or gutter issues
Water is one of the most common culprits behind foundation cracks.
Improper drainage, like clogged gutters, can allow rainwater to pool near the base of your home. When water isn’t channeled away from the foundation, it seeps into the ground and adds to hydrostatic pressure or increases the risk of soil erosion and settlement.
No matter the cause, foundation cracks are often a sign that something is off—and they shouldn’t be ignored.
Bad drainage can cause water to pool near your foundation and cause hydrostatic pressure.
How we fix cracks in concrete foundation walls
As a foundation repair company, we take a comprehensive approach to fixing foundation cracks. When choosing a contractor, it’s crucial to select one that conducts a thorough inspection of your home and provides reliable, proven solutions. Here’s a look at our process for foundation repair.
1. Thorough inspection
First, we conduct a detailed inspection to understand the type, size, and location of the cracks. We evaluate the overall health of your foundation and identify the root cause—whether it’s soil movement, hydrostatic pressure, or foundation settlement.
2. Custom repair solutions
Once we identify the problem, we recommend a customized repair plan specific to your home. Depending on the severity and type of crack, we may use:
- Carbon fiber. Carbon fiber is a strong, lightweight material that works well for foundation cracks. We apply carbon fiber strips directly to the wall, which help stabilize it and prevent the crack from spreading. It's an effective, long-term solution that provides reinforcement without taking up any extra space in your basement.
- Power Brace Wall System. Power braces are metal beams installed along the inside of the foundation wall. They're designed to stabilize the wall and prevent movement and settlement. This method is great for cracks that are more significant but haven't caused significant structural issues. They can be adjusted over time to slowly shift the wall back into place, making them a great solution for stabilization and gradual correction.
- Wall anchors. Wall anchors are steel plates installed in the ground outside the foundation and connect to your wall with a long steel rod. This method is effective for larger cracks caused by external pressure, like soil movement or hydrostatic pressure. They essentially "pull" the wall back into place.
- Piers. Piers are installed beneath the foundation to lift and support the structure. If your cracks are due to significant foundation settlement, piers are often the best solution. They transfer the weight of your home from unstable soil to stronger, deeper layers of soil or bedrock. This stops further settlement and can even lift the foundation back to its original position.
- EverBrace Wall System. This system is designed for walls that have significant structural damage. It involves installing steel corrugated panels and beams inside the basement, creating a strong barrier that transfers the load from the failing wall to the new system.
Common DIY methods and why they fall short
Some homeowners attempt to fix foundation cracks on their own, using methods that may seem great at first but can lead to bigger problems down the line. Here are the most common DIY methods and why we do not recommend them.
1. Caulk or store-bought sealant
If you apply caulk incorrectly, it can trap moisture and lead to mold.
The method: Many DIYers try to fill the cracks with caulk, epoxy, or another sealant available at the big box stores.
Why it's ineffective: These materials only provide a superficial fix. While they may temporarily seal the crack, they don’t address the underlying cause. Also, incorrect application can lead to trapped moisture, which can mold growth and even, weaken the wall over time.
2. Hydraulic cement
The method: Some DIYers use hydraulic cement to patch the crack, as it’s designed to harden quickly and stop water leaks.
Why it's ineffective While hydraulic cement can stop leaks, it’s not flexible. It doesn’t move with the natural shifts of the foundation, making it a short-term solution at best. As the foundation continues to shift, the crack may reopen or spread.
3. Interior waterproofing paint
The method: Homeowners sometimes apply waterproofing paint to the interior of foundation walls, believing it will seal cracks and stop water penetration.
Why it's ineffective: Waterproofing paint may mask the problem but won’t eliminate the root cause. It also doesn’t provide the necessary structural support for the wall, leaving your home vulnerable to further damage.
Why we're against DIY foundation repair
Everyone loves a good DIY project—it can be a little fun, a time-saver, and most importantly, a money-saver. But when it comes to repairing foundation cracks, it's best to leave it to the professionals. Here’s why.
1. Surface repairs don’t address the root problems
A crack in your foundation is often a symptom of a larger issue.
Simply filling the crack with store-bought sealant might mask the problem for a while, but it won’t address what caused the crack in the first place.
Professionals have the tools and expertise to diagnose the root cause—whether it’s drainage issues, soil movement, or structural concerns—and fix it at its source.
2. Foundation repairs require specialized knowledge
We’re all for a good DIY project, but foundation repair isn’t one of them. Here’s a behind-the-scenes look at a recent foundation repair job that required excavation and drilling into the foundation.
Foundation repairs aren’t like patching up drywall. They often involve technical knowledge of soil conditions, load-bearing calculations, and waterproofing techniques.
Without the right expertise, DIY repairs can inadvertently cause more damage.
3. Your home’s structural integrity is at stake
Your home’s foundation is literally what holds everything up. If cracks are left unaddressed or improperly repaired, they can get worse and potentially compromise your home’s structural integrity. What starts as a small crack could evolve into a much larger, more expensive repair if not handled correctly from the beginning.
What you should do instead
When you spot cracks in your foundation, the best course of action is to call in a professional for an inspection. Here’s why.
- Expert diagnosis. A professional can assess the type, size, and location of the crack and determine whether it’s a cosmetic issue or a sign of a larger structural problem.
- Long-term solutions. Professionals don’t just patch the crack—they offer long-term solutions that address the underlying causes and prevent future cracks from forming.
- Peace of mind. Having an expert evaluate your foundation gives you peace of mind that your home is safe, stable, and secure.
At Thrasher Foundation Repair, we offer free home inspections to help homeowners understand what’s happening with their foundation and how to fix it. Our experienced team will take the time to explain the issue, answer your questions, and provide a clear plan for repair.
Schedule a free inspection
If you’ve noticed cracks in your concrete foundation walls, don’t wait for them to get worse. Reach out to our team to schedule a free home inspection.
We’ll help you identify the issue, explain your options, and guide you through the repair process—no hard sales pitch, just honest advice.
At Thrasher, we’ve been helping homeowners protect their homes for 50 years. Our approach is simple: we provide solutions that work, backed by experience, integrity, and a genuine commitment to your peace of mind.
Get started today by scheduling your free inspection. Your home’s foundation is too important to leave to chance, and we’re here to help every step of the way.
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Additional resources for you
If you found this article helpful, there’s plenty more where that came from. Our extensive library is packed with information about foundation repair. Below are a few recommended reads, but feel free to explore our blog for more insights.
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