The short answer
What Causes Cracks to Widen
Foundation cracks spread when the soil beneath your home expands and contracts with moisture. In a climate with wet and dry seasons, the ground can swell when wet and shrink when dry, putting repeated stress on the concrete. Water that seeps into a crack can also erode the soil underneath, making the crack worse over time.
Temperature changes and tree roots nearby add more pressure. A crack that looks minor in dry weather can open wider after heavy rain. You might notice the crack lengthening along the wall or new small cracks branching off from the original one. Not all cracks grow, but many do if the underlying cause is not addressed.
Signs Your Crack Is Spreading
Check your foundation cracks every few months, especially after a wet season. Measure the width with a simple ruler or a crack-monitoring gauge. If the gap widens by more than a millimeter, that is a sign of movement. Also look for new cracks near doors, windows, or corners where the foundation meets the walls.
Other clues include doors that start sticking, windows that no longer close smoothly, or gaps appearing between the foundation and the siding. You might also see water stains or efflorescence, a white powdery residue, near the crack. These signs suggest moisture is actively working on the crack.
If you notice any of these changes, it is worth having a water damage inspection to see what is happening below the surface.
- Crack widens by more than 1/8 inch over a year
- New cracks appear near the original one
- Doors or windows become hard to open
- Water stains or white residue near the crack
- Floor feels uneven or slopes in one area
- Crack extends beyond the foundation into the wall
When to Take Action
A small, stable hairline crack may not need immediate repair, but a crack that is growing or letting in water should be addressed. Water intrusion through a foundation crack can lead to mold, wood rot, and more serious structural issues. The longer you wait, the more likely the crack will spread and the damage will deepen.
You can slow the spread by improving drainage around your home. Make sure gutters and downspouts direct water away from the foundation, and grade the soil so it slopes away from the house. Fixing leaks from pipes or irrigation systems also reduces moisture near the foundation.
For a crack that is actively widening, a foundation stabilization service can help. Pros assess the soil conditions and may recommend underpinning or other methods to stop movement. Acting early often prevents a bigger repair later.
How Water Damage Plays a Role
Water is the main driver of crack growth. When rain or groundwater saturates the soil, it pushes against your foundation walls. As the water dries, the soil shrinks and can pull away, leaving voids. This cycle of swelling and shrinking can cause cracks to open and close, gradually widening them.
If a crack allows water into your crawlspace or lower level, you might also face dampness, musty odors, or mold growth. In that case, you need both crack repair and moisture control. Structural drying and dehumidification can help dry out the area after a leak or flood, reducing the moisture that feeds the problem.
If you notice water pooling near the foundation after heavy rain, that is a warning sign that should not be ignored. Keeping the soil dry around your home is one of the most effective ways to slow crack growth.
What the Pros Usually Do
When you call local water damage pros for a foundation crack, they start by inspecting the crack and the surrounding soil. They measure the width, check for movement, and look for water entry points. They may use moisture mapping to detect hidden dampness in the walls or floor.
Depending on what they find, the work can involve sealing the crack with a flexible epoxy or polyurethane, installing drainage, or stabilizing the foundation with piers or underpinning. The goal is to stop the crack from growing and prevent water from getting in. The exact approach depends on the crack size, the soil type, and the cause.
Policies vary, and your insurer decides what is covered. Check your policy to see if foundation damage from water is included.
Talk to someone now
Water keeps spreading into floors and walls, so it is worth acting early. Calls are answered 24/7.
Call Now (817) 799-6732Frequently asked questions
Can I fix a foundation crack myself?
You can fill a small, stable hairline crack with a masonry sealant, but that only covers the surface. If the crack is widening or letting in water, a professional repair is safer. DIY fixes may hide the problem without addressing the cause.
How fast do foundation cracks spread?
There is no set speed. Some cracks stay stable for years, while others widen noticeably within a season. Heavy rain, drought, and poor drainage can speed up the process. Monitoring the crack width every few months gives you a clearer picture.
Will my insurance cover foundation crack repair?
Coverage depends on the cause. Sudden water damage from a burst pipe might be covered, while gradual settling or poor maintenance usually is not. Policies vary, and your insurer decides what is covered. Review your policy and ask your agent about specifics.