Foundation Crack Repair in South Farmingdale, NY

Stop Foundation Leaks Permanently

Professional crack injection and structural repairs that actually work the first time.

Hear About Us

Professional Foundation Repair Contractors

Your Basement Stays Dry Year-Round

You walk downstairs after the heaviest storm and see completely dry floors. No more scrambling for buckets when the weather turns. No more wondering if that crack is getting worse or if water damage is spreading behind your walls.

That’s what happens when foundation cracks get fixed right. Your basement becomes usable space again instead of a source of constant worry. You stop losing sleep over structural problems and start enjoying the peace of mind that comes with a solid foundation.

The difference between a proper repair and a temporary patch becomes obvious the moment you need it most. Professional crack injection doesn’t just seal the surface – it creates a permanent barrier that moves with your foundation as it naturally settles.

South Farmingdale Foundation Specialists

We Fix What Others Miss

We at Diamond Masonry & Waterproofing LLC have been solving foundation problems for Long Island homeowners who need repairs that actually last. We’ve seen every type of crack, leak, and structural issue that affects homes in Nassau County.

Most foundation problems in South Farmingdale stem from the same root causes – clay soil movement, freeze-thaw cycles, and settling that’s completely normal for homes built in the 1950s through 1980s. We know exactly how to address these issues permanently.

You’re not getting a sales pitch from us. You’re getting straight answers from contractors who’ve been doing this work long enough to know what works and what doesn’t.

Foundation Crack Injection Process

Here's Exactly What We Do

First, we inspect every crack to determine whether it’s structural or just settling. This matters because the repair method changes based on what’s actually causing the problem. We’re looking at crack width, location, and any signs of active movement.

Next comes the actual crack injection. We use professional-grade polyurethane or epoxy that’s designed to bond with concrete and flex as your foundation moves. This isn’t the stuff you buy at Home Depot – it’s industrial-grade material that creates a permanent seal.

The injection process involves drilling small ports along the crack and injecting material under pressure until it completely fills the void. We work from the bottom up to ensure complete coverage. Most repairs cure within hours, but we recommend waiting 24 hours before testing with water.

Finally, we clean up and explain what we’ve done. You’ll know exactly what materials we used, how long the repair should last, and what to watch for going forward.

Ready to get started?

Explore More Services

About Diamond Masonry & Waterproofing

Get a Free Consultation

Complete Foundation Repair Services

More Than Just Crack Repair

Every foundation crack repair includes a complete inspection of your basement walls and floor. We’re looking for signs of ongoing issues that could cause new problems down the road. You get a full picture of your foundation’s condition, not just a quick fix.

Our crack injection work comes with materials specifically chosen for Long Island’s soil conditions and climate. We’re dealing with freeze-thaw cycles, clay soil movement, and the kind of settling that’s common in South Farmingdale’s housing stock. The materials we use are designed for these exact conditions.

When structural integrity is a concern, we can handle reinforcement work alongside crack repair. Sometimes a crack is telling you about a bigger issue that needs attention. We’ll identify these situations during our inspection and explain your options clearly.

You also get our honest assessment of whether additional waterproofing makes sense for your situation. Not every basement needs a full waterproofing system, but some do. We’ll tell you the difference.

How long does foundation crack injection actually last?

Professional crack injection with the right materials typically lasts 10-20 years or more, depending on your foundation’s ongoing movement. The key is using polyurethane or epoxy that’s designed to flex with normal settling. Cheap sealants fail because they’re rigid – they crack when your foundation moves even slightly. We use materials that bond permanently with concrete but maintain flexibility. Most of our crack repairs come with warranties because we’re confident in the materials and methods we use. The injection creates a seal that’s often stronger than the surrounding concrete.

Can I just seal foundation cracks myself with store-bought products?

You can try, but most DIY crack repair products are temporary solutions at best. Store-bought sealants typically only address the surface of the crack, not the full depth where water is actually entering. Professional crack injection involves drilling ports and injecting material under pressure to completely fill the void. DIY products also can’t handle the pressure that builds up behind foundation walls during heavy rains. We’ve repaired plenty of cracks where homeowners tried DIY fixes first – it usually just delays the inevitable and sometimes makes the permanent repair more complicated.

How do I know if a foundation crack is structural or just cosmetic?

Structural cracks are typically wider than 1/4 inch, horizontal, or show signs of recent movement like fresh concrete dust or misaligned edges. Cosmetic settling cracks are usually thin, vertical, and stable. But the real test is what’s happening around the crack – are doors sticking, floors uneven, or walls showing stress? Location matters too. Horizontal cracks or cracks near corners are more likely to indicate structural issues. During our inspection, we measure crack width, check for active movement, and look at your home’s overall settling patterns. When in doubt, it’s always better to have a professional evaluation than to guess.

Will fixing foundation cracks stop all water problems in my basement?

Crack repair stops water that’s entering through those specific cracks, but basements can have multiple water entry points. If water is also coming through the foundation walls, floor joints, or around windows, you’ll need additional waterproofing. During our inspection, we identify all potential water sources, not just the obvious cracks. Sometimes crack repair is all you need. Other times, it’s part of a larger waterproofing strategy. We’ll be honest about what you’re dealing with and prioritize repairs based on what’s causing the most immediate problems. Most homeowners see significant improvement just from proper crack repair.

How much does professional foundation crack repair typically cost?

Most crack injection repairs range from $300-800 per crack, depending on length and complexity. That might seem expensive compared to a $20 tube of sealant, but consider the cost of repeated repairs, water damage, or structural issues if the problem isn’t fixed properly. We provide free inspections and transparent pricing before any work begins. The investment usually pays for itself by preventing bigger problems and eliminating the need for repeated temporary fixes. Complex structural repairs cost more, but we’ll explain exactly what’s needed and why before you make any decisions.

What's the difference between polyurethane and epoxy crack injection?

Polyurethane stays flexible after curing, making it ideal for cracks that might experience slight movement from normal foundation settling. It’s also better for actively leaking cracks because it can cure in the presence of water. Epoxy creates a rigid repair that’s stronger than the surrounding concrete, but it can crack if your foundation moves. We choose the material based on your specific situation – crack location, foundation type, soil conditions, and whether the crack shows signs of movement. Both materials create permanent repairs when used correctly, but the wrong choice for your situation can lead to repair failure.

Local Resources