Your home’s foundation is one of the most important parts of the structure. Over time, cracks and bowing walls can develop due to soil pressure, moisture issues, or natural settling. Understanding these problems and knowing how to fix them is critical for keeping your home safe and in good structural condition. In this article, I will break down the different types of foundation cracks, what causes them, and the best ways to repair both cracks and bowing foundation walls.
Not all cracks are a cause for concern. Some cracks are normal and expected while others can be an indication of serious structural issues. Here is a quick breakdown of the most commonly found foundation cracks while performing home inspections in New Jersey.
- Hairline Cracks – These are thin surface cracks that usually occur as concrete cures. They are typically not a cause for concern, but they should be monitored for worsening conditions.
- Vertical Cracks – These are common in poured concrete foundations, these cracks can result from natural settling of the structure. If vertical cracking begins to widen, it could indicate a major issue.
- Horizontal Cracks – These types of cracks are generally more serious. They often appear in block foundations and can indicate excessive soil pressure pushing against the wall which creates this type of structural cracking.
- Stair Step Cracks – These cracks form in brick or block foundations, these cracks suggest shifting or settlement. These cracks can be caused by differential movement.
- Diagonal Cracks – These types of cracks are often caused by uneven settling or water collecting too close to the exterior foundation walls of the home.
It is useful to have a basic overview of how foundation cracks are repaired in homes.
The correct method of repair depends on the severity of the crack. Here are some of the most common foundation crack repair solutions.
Epoxy or Polyurethane: Injection This is for narrow and thin cracks.
- Excellent for vertical or diagonal cracks in poured concrete foundation walls.
- Epoxy injection strengthens the crack, while polyurethane is more flexible and water-resistant.
- The process involves cleaning the crack, injecting the material, and allowing it to dry and too cure.
Hydraulic Cement: This is for nonstructural cracking
- Used to seal minor cracks and prevent water from pushing through the cracking
- Requires chiseling or grinding out the crack, wetting the surface, and injecting hydraulic cement that expands as it cures and dries.
Carbon Fiber Straps: For Preventing Further Movement
- Used for minor to moderate cracking or bowing in poured concrete or block foundation walls that might get worse over time.
- Carbon fiber straps are bonded to the wall with epoxy to add strength and prevent widening or further movement of the foundation walls. These straps are typically applied every five feet down the length of the wall from the interior.
Underpinning: For Structural Settlement Issues
- Underpinning is needed when major movement causes large cracks or foundation instability.
- Involves installing steel piers, helical piers, or push piers to stabilize and possibly lift the foundation.
Fixing Bowing and Moving Foundation Walls
Bowing walls occur when soil pressure or water collection pushes laterally against the foundation. Here are some of the most effective ways to stabilize and repair bowing foundation walls:
Carbon Fiber Reinforcement: For Moderate to Major Bowing, Less than 2 Inches
- Carbon fiber straps are applied top to bottom along the foundation wall to prevent further wall movement.
- Works best for moderate horizontal cracking or bowing before they can get worse over time.
Wall Anchors: For Moderate Bowing, Up to 3 Inches
- Metal anchors are installed in the ground outside the foundation and connected to steel rods inside the foundation wall.
- The system is tightened gradually to stabilize and straighten the wall over time.
Steel I-Beams: For Moderate to Severe Bowing
- Vertical steel beams are installed inside the foundation wall as a buttress to brace the wall against inward hydraulic pressure.
- This method of repair requires periodic tightening to maintain stability.
Helical Tiebacks: For Severe Bowing or Leaning Walls
- Helical anchors are drilled into the ground at an angle and attached to the wall.
- The system is tightened to stabilize and straighten the wall.
Excavation and Wall Rebuilding: for major wall bowing and movement (For Extreme Cases)
- Involves excavating out soil, rebuilding the foundation wall, and improving drainage to prevent future problems.
- This is a last resort and very expensive solution for walls that are severely damaged and beyond what typical repair methods can accomplish.
As NJ Home inspectors, foundation problems are always a major focus during an inspection. They are one of the most important issues paramount on the minds of home inspection clients.
- Visible Cracks – Assessing the size, pattern, and severity of cracks to determine whether they are cosmetic or structural.
- Bowing or Leaning Walls – Checking for inward movement that could signal excessive soil pressure.
- Moisture Issues – Looking for water damage, poor drainage, and high humidity levels that could weaken the homes foundation.
- Structural Red Flags – Uneven floors, sticking doors/windows, and drywall cracks that suggest foundation movement.
- Repair Recommendations – If major foundation issues are present, I advise clients to seek professional structural engineer evaluation before buying or selling a home.
Final thoughts:
Foundation issues should never be ignored. They can become worse over time and seriously impact your home’s structural integrity. Whether the home you are living in, or purchasing has cracking, bowing walls, or settling. Understanding your repair options can help you take action before the foundation wall problems get worse. Having a thorough and comprehensive NJ home inspection can find these problems and give you the opportunity to ask for credits or possibly correction. Regular inspections and proper maintenance will go a long way in keeping your foundation strong for years to come.