Sinking Foundation: Causes, Signs, and Repair Solutions in Long Island, Brooklyn, and Queens

A sinking foundation is one of the most serious structural issues a homeowner can face. If left unchecked, it can lead to severe damage, safety concerns, and costly repairs. For homeowners in Long Island, Brooklyn, and Queens, understanding the causes, warning signs, and repair solutions for a sinking foundation is crucial to maintaining a safe and stable home.

Blame the State of New York… 

Yes, properties in Long Island, Brooklyn, and Queens are more vulnerable to sinking foundation damage than many other areas in the U.S. due to several factors:

1. Soil Composition & Weak Foundations

• Sandy and Clay-Based Soil: Long Island’s soil is primarily sandy and silty, which can shift easily under pressure. Brooklyn and Queens have more clay-heavy soil in certain areas, which expands and contracts with moisture, leading to foundation movement.
• Fill Soil in Coastal Areas: Many areas, especially in Brooklyn and Queens, were built on man-made fill rather than solid bedrock, making the ground unstable over time.

2. High Water Table & Coastal Proximity

• Much of Long Island, Brooklyn, and Queens are at or near sea level, with a high water table that can cause soil erosion and instability beneath foundations.
• Tidal and Storm Surge Effects: Rising sea levels and extreme weather events, like hurricanes and nor’easters, contribute to ground saturation and shifting foundations.

3. Urban Infrastructure & Construction Pressure

• Heavy construction and urban development put significant stress on the ground, leading to soil compaction and settling.
• Older Buildings with Weak Foundations: Many homes in Brooklyn and Queens were built over a century ago, often with less robust foundation techniques, making them prone to sinking over time.

4. Freeze-Thaw Cycles & Weather Conditions

• Harsh winters cause repeated freeze-thaw cycles, leading to frost heaving, which shifts and weakens foundations.
• Heavy rainfall in the region can cause soil to wash away, further increasing settlement risks.

5. Seismic Activity

• While not as active as California, the NYC region, including Long Island, Brooklyn, and Queens, does experience minor earthquakes that can contribute to long-term foundation instability.

Properties in Long Island, Brooklyn, and Queens are at a higher risk of sinking foundation damage compared to much of the U.S., mainly due to unstable soil, a high water table, urban stress, and climate factors. Property owners should consider foundation inspections, waterproofing, and soil stabilization to mitigate risks.

Sinking Foundation Signs: How to Identify the Problem

Recognizing the early signs of a sinking foundation can save you thousands of dollars in repairs. Look for these red flags:

• Cracks in Walls and Floors – Large, expanding cracks in drywall, tile, or concrete floors may indicate foundation movement.
• Uneven or Sloping Floors – If floors start to slope or feel uneven, the foundation may be settling.
• Sticking Doors and Windows – Difficulty opening and closing doors and windows can signal foundation shifts.
• Gaps Around Doors and Windows – Visible spaces forming around door frames and window sills suggest foundation movement.
• Leaning or Tilting Chimney – If your chimney is pulling away from the house, the foundation may be sinking.
• Basement Water Intrusion – Water leaks or moisture in the basement can be a sign of shifting foundations allowing water penetration.
• Bowing Walls: It is common for the walls to bend, crack and bow when the foundation of a property sinks.

Here are some foundation repair and waterproofing solutions for properties in Long Island, Brooklyn, and Queens to prevent and fix sinking foundation issues:

Foundation Repair Solutions

Here are the best foundation repair solutions that are particular to the unique environment and soil conditions of Long Island, Brooklyn, and Queens. 

A. Mudjacking (Slab Jacking)

• Best for: Sunken concrete slabs, patios, and driveways.
• How it works: A grout mixture is injected beneath the slab to lift it back into place.
• Pros: Cost-effective and non-invasive.
• Cons: Not ideal for severe foundation settlement.

B. Helical & Push Piers

• Best for: Homes with sinking foundations.
• How it works: Steel piers are driven deep into stable soil or bedrock to provide a permanent foundation support system.
• Pros: Long-lasting and prevents further settlement.
• Cons: Higher cost than mudjacking but offers a permanent fix.

C. Concrete Underpinning

• Best for: Severe foundation failure.
• How it works: Additional concrete footings are poured beneath the existing foundation to add extra support in the underpinning process. 
• Pros: Strengthens foundations permanently.
• Cons: Can be expensive and requires excavation.

D. Polyurethane Foam Injection

• Best for: Minor sinking in slabs.
• How it works: Expanding foam is injected under concrete to raise and stabilize it.
• Pros: Fast-acting, lightweight, and minimally invasive.
• Cons: Not suitable for deep foundation issues.

2. Waterproofing & Soil Stabilization

A. Exterior Waterproofing Membranes

• Best for: Homes with water intrusion and high water tables.
• How it works: A waterproof membrane is applied to the foundation exterior to block moisture.
• Pros: Keeps water away from the foundation.
• Cons: Requires excavation around the home.

B. Interior Drainage Systems (French Drains & Sump Pumps)

• Best for: Preventing water damage and hydrostatic pressure.
• How it works: French drains collect and redirect water, while sump pumps remove excess moisture.
• Pros: Effective against flooding and leaks.
• Cons: Requires proper installation for efficiency.

C. Soil Stabilization with Polymer Injections

• Best for: Loose and shifting soil.
• How it works: Polymer solutions are injected into the soil to solidify and prevent erosion.
• Pros: Prevents future settlement.
• Cons: Best combined with other foundation support solutions.

3. Preventative Maintenance Tips

• Regular Foundation Inspections – Identify early signs of cracks or sinking.
• Proper Drainage – Ensure gutters and downspouts direct water away from the foundation.
• Soil Grading – Maintain a slope away from the house to prevent water pooling.
• Seal Foundation Cracks – Use epoxy or polyurethane injections for small cracks.
• Waterproof Basements & Crawl Spaces – Prevent moisture damage before it weakens the foundation.

Sinking Foundation Repair Cost: What to Expect?

The cost to fix a sinking foundation varies based on the severity of the issue and the repair method required. Here’s a rough estimate:

• Minor Repairs (crack sealing, drainage fixes) – $500 to $3,000
• Mudjacking or Slabjacking – $3,000 to $7,000
• Underpinning with Piers – $5,000 to $25,000 (depending on the number of piers needed)
• Full Foundation Replacement – $30,000 or more (for extreme cases)

The exact sinking foundation repair cost depends on the extent of the damage, accessibility, and the contractor you hire.

Why Choose Zavza Seal LLC for Sinking Foundation Repair?

At Zavza Seal LLC, we specialize in professional foundation repair services for homeowners in Long Island, Brooklyn, and Queens. Here’s why we are the top choice:

• Experienced Professionals – With years of expertise, we diagnose and fix foundation issues with precision.
• Custom Solutions – We tailor repair methods to the unique needs of your property.
• Advanced Technology – We use the latest equipment and high-quality materials for long-lasting results.
• Warranties and Guarantees – We stand by our work with up to 20 years of warranty, ensuring peace of mind for our customers.
• Customer Satisfaction – We prioritize client needs, providing reliable, transparent, and affordable solutions.

Final Thoughts

A sinking foundation is a serious issue that should not be ignored. Whether you’re noticing early sinking foundation signs or require sinking foundation repair, addressing the problem promptly can prevent further damage and reduce costs. If you’re in Long Island, Brooklyn, or Queens, contact Zavza Seal LLC today for a professional assessment and a lasting solution.

Need Foundation Repair?

Call us now or visit our website to schedule a free consultation and protect your home from foundation failure!