Foundation issues are one of the major concerns for many Texas homeowners. It is important to understand when a foundation problem is a simple fix and when it requires professional attention.
In this blog, we will discuss warning signs to watch for in your foundation, how to catch small issues, and low-cost repairs homeowners can make for foundation cracks and exposed post-tension cable ends.
Types of Cracks in Post-Tension Slab
There are two common types of cracks in post-tension foundation:
Corner Cracks
In the Houston area, most homes with concrete slabs have corner cracks, which are usually not a sign of foundation failure and can often be treated easily by the homeowner for under $5.
If these cracks are left untreated, water can enter the crack and cause the crack to increase in size. Eventually, the corner section may fall off completely. Even then, the foundation isn’t failing, but minor repairs are needed to restore support to the brick or framing above that corner.
In addition, cracks can create a conducive environment for wood-destroying insects to enter the structure of the home.
Vertical Cracks
Most exterior vertical cracks seen on a foundation are not a concern if they are not wide enough to look problematic. These cracks can be treated in the same manner as the foundation corner cracks. For these cracks, you can use DIY repair techniques.
Cracks Requiring Professional Assessment
Some cracks are an indication of foundation settling and may require foundation repair. These cracks are over ¼ inch wide, as shown in the picture below. A crack like this would require further evaluation by a foundation company to determine whether the foundation needs repair. Homeowners should never compromise on the stability of a foundation.
Why Foundation Stability Matters for Texas Homeowners
Your home’s foundation is more than just a concrete base. It is the structural backbone that supports everything above it. In Texas, unique soil conditions and extreme weather make foundations vulnerable to movement.
Expansive clay soils, common across the state, absorb water and swell during rainy months, then shrink and crack during droughts. Combined with seasonal temperature swings and inconsistent drainage, it becomes the perfect condition for foundation shift.
What Happens When a Post-Tension Cable Breaks
When a post-tension cable snaps, it releases a huge amount of stored energy. The results can include:
- Cracks or separation in your concrete slab
- Popping or loud “gunshot” sounds when the break occurs
- Uneven floors or gaps forming between walls and floors
- Weakened load-bearing capacity in that section of the foundation
In severe cases, a broken cable can even cause concrete blowouts, where part of the slab or garage floor breaks apart due to sudden force. If you suspect a post-tension cable is broken, stop all DIY attempts and call a qualified structural engineer.
Exposed Post Tension Cables: Why They’re a Red Flag
One of the easiest warning signs to spot in a foundation is exposed post-tension cables. These cables are meant to stay completely sealed inside the concrete. When you can see a cable poking out or corroded along the edges of the slab, it’s a sign that the foundation has shifted, cracked, or been improperly repaired in the past.
Exposed cables are serious because they can:
- Rust and weaken over time, reducing the foundation’s strength
- Lead to water intrusion through cracks
- Eventually snap under pressure
If you ever see exposed post-tension cables, do not cut, grind, or patch them yourself. The tension inside is extreme. Cutting one can be dangerous and cause injury or further damage to the slab.
Common Causes of Post-Tension Cable Damage
Texas’ unique soil conditions and weather patterns make post-tension foundation issues fairly common. Here are the most frequent culprits behind post-tension cable issues:
- Soil movement: Expansive clay soils swell when wet and shrink during dry spells, stressing the slab.
- Improper drainage: Poor yard grading or leaking plumbing increases soil moisture and slab pressure.
- Poor construction or cable placement: Misaligned or overstressed cables can fail early.
- Corrosion: Moisture entering the concrete can cause steel cables to rust, especially near exposed areas.
- Heavy loads: Large additions, vehicles, or equipment can overstress certain sections of the foundation.
Post-Tension Cable Repair: What Professionals Do
If you’re dealing with a damaged cable, here’s what a professional post-tension cable repair typically involves:
- Inspection & Location: A licensed engineer identifies which cables are broken, corroded, or exposed.
- Accessing the cable: The affected area of the concrete is carefully cut open without compromising the slab.
- Repair or replacement: The damaged section of the tendon is spliced or replaced, then re-stressed to the correct tension level.
- Re-sealing: The area is patched with high-strength, moisture-resistant concrete to prevent future corrosion.
This isn’t a quick DIY job; it requires special tools and certifications to handle safely.
Post-Tension Cable Repair Cost: What to Expect
One of the first questions homeowners ask is about the post-tension cable repair cost. The actual cost depends on the severity of damage; however, on average:
- Minor cable exposure repair cost: $300–$800
- Partial tendon replacement cost: $1,000–$2,500
- Full post tension foundation repair (involving multiple cables and slab correction): $5,000–$15,000+, depending on severity
However, costs can vary widely based on factors like location, foundation size, accessibility, and soil conditions.
The good news? Catching issues early, especially exposed post-tension cables, can drastically reduce repair expenses and prevent larger structural failures.
Post-Tension Foundation Repair: When It’s Time to Act
A full post-tension foundation repair is often needed when the damage extends beyond one or two cables. Signs it’s time to call a professional include:
- Wide cracks running across your slab or walls
- Uneven or sloping floors
- Gaps between the ceiling and the walls
- Doors and windows that stick
- Visible cable ends or rusted anchor points
During a foundation inspection, a professional may use radar or X-ray imaging to locate damaged tendons before recommending repair or re-stressing.
DIY Method to Treat Foundation Cracks
The DIY method can only help if the cracks are minor and are not caused by some structural defect.
Go to your local hardware store and purchase some gray silicone sealant. You want the gray color to blend in with the color of the concrete. The cost of these tubes is typically under $5. You may have to purchase a caulk gun, but the gray silicone is also available in plastic tubes, where you cut the nipple off with a knife.
Apply the silicone sealant to the inside of the crack. Insert enough sealant so that it comes out of the crack. Scrape off excess with a straight edge, a piece of cardboard, etc. “Trick of the trade,” wiping the surface off with a damp sponge will remove excess silicone and leave a smooth finish.
DIY Technique for Post-Tension Slab Cable Repairs
Cable ends protruding from post-tension slabs should be covered with a concrete patch to prevent the cable ends from rusting. When rusting occurs, the cables grow thicker and eventually cause other foundation issues.
To repair, purchase some concrete patch from the hardware store.
Use a putty knife or a hand trowel to apply the concrete patch to the exposed cable end. “Trick of the trade,” wiping the surface off with a damp sponge will remove excess silicone and leave a smooth finish.
Inspect your foundation annually for cracks and exposed cable ends. Making low-cost repairs now can prevent more costly repairs later.
Final Words
Your foundation literally supports your home. Texas soil, which is constantly shifting, vigilance is key to keeping the foundation in good condition. Whether it’s exposed post-tension cables or a deeper post-tension foundation repair, addressing the issue early is always cheaper and safer than waiting for structural damage to spread.
If you have any questions about whether the crack is causing foundation problems, contact us. Our experts will help you protect your home.
Frequently Asked Questions
Q: How much does foundation repair typically cost in Texas?
Foundation repairs in Texas usually range from $3,000 to $10,000, depending on the type of damage and foundation system. Smaller fixes, like sealing minor cracks, cost less, while major structural or post-tension foundation repairs can be on the higher end.
Q: What’s the biggest difference between DIY and professional foundation repair?
DIY fixes might hide surface issues, but professionals address the root cause — things like soil movement, drainage, or damaged post-tension cables. A licensed expert also ensures repairs meet safety standards and prevent future structural problems.
Q: How often should I have my foundation inspected?
It’s smart to schedule a foundation inspection every 2–3 years, or sooner if you notice cracks, uneven floors, or sticking doors. Texas weather can change soil conditions fast, so regular checkups help catch issues early.
Q: Can a home inspection detect foundation problems?
Yes, a home inspection can reveal early signs like sloping floors, wall cracks, or exposed post-tension cables. If anything looks suspicious, your inspector may recommend a structural or foundation specialist for a deeper evaluation.
