Basement Waterproofing in Merrick, NY

Get Your Basement Completely Dry

Professional waterproofing that stops water problems for good, not just until the next storm.

Hear About Us

Merrick Waterproofing Services

What a Truly Dry Basement Means

You walk downstairs after the heaviest rainstorm and find exactly what you expect: a completely dry basement. No puddles in the corners. No musty smell hitting you halfway down the stairs. No checking and rechecking your stored belongings.

Your basement becomes usable space again. Storage that stays dry. A workshop that doesn’t smell like mildew. Maybe even a family room where your kids can actually play without you worrying about what they’re breathing.

The constant background stress disappears. You stop checking weather forecasts with dread. You stop rushing home during storms to move things off the floor. You just live in your house without that nagging worry about what’s happening downstairs.

Merrick Basement Waterproofing Company

We Know Long Island Basements

We’ve been solving water problems for Merrick homeowners who’ve tried everything else. We understand how Long Island’s high water table and clay soil create unique challenges that generic solutions can’t handle.

We’re not the guys who show up, spray some sealant on your walls, and call it waterproofing. We dig deeper—literally and figuratively—to find why water keeps getting into your basement and fix it at the source.

Every job starts with understanding your specific situation. Different houses fail in different ways, and cookie-cutter approaches leave you with the same problems six months later.

Basement Waterproofing Process

How We Actually Stop Water

First, we figure out where water is coming from. Foundation cracks, hydrostatic pressure, poor exterior drainage—each problem needs a different approach. We don’t guess; we investigate until we know exactly what’s happening.

Next, we address the root cause. Sometimes that means exterior basement waterproofing to redirect water away from your foundation. Other times it’s interior waterproofing with professional-grade basement wall sealer and drainage systems. Often it’s both.

We use materials designed for Long Island conditions. The basement sealer that works in Arizona won’t hold up against our water table and freeze-thaw cycles. We know which products actually last here because we’ve seen what fails after five years.

Finally, we test everything before we leave. You’ll see exactly how water moves around your foundation now and why it won’t be getting into your basement anymore.

Ready to get started?

Explore More Services

About Diamond Masonry & Waterproofing

Get a Free Consultation

Complete Waterproofing Solutions

What You Get With Our Service

Our basement waterproofing services include both interior and exterior solutions depending on what your house needs. Exterior basement waterproofing involves excavation, membrane installation, and drainage improvements that stop water before it reaches your foundation walls.

Interior basement waterproofing focuses on managing water that does penetrate, using basement waterproofing sealer, drainage channels, and sump pump systems that redirect water safely away from your living space.

We handle foundation crack repair as part of the waterproofing process because cracks are often how water finds its way in. Each crack gets properly cleaned, sealed, and reinforced to prevent future water infiltration.

You’ll also get a clear explanation of what we did and why, plus practical advice for maintaining your newly waterproofed basement. No mystery treatments or proprietary systems you can’t understand.

How long does basement waterproofing actually last?

Professional basement waterproofing should last 15-25 years when done correctly with quality materials. The key is addressing the actual source of water intrusion, not just treating symptoms. Interior waterproofing systems with proper drainage typically require minimal maintenance, while exterior waterproofing can last even longer since it prevents water from reaching your foundation walls. Cheap sealants that just coat your walls might last 2-3 years before failing, which is why many homeowners end up waterproofing multiple times.

Should I choose interior or exterior basement waterproofing?

It depends on your specific water problem and budget. Exterior basement waterproofing costs more upfront but provides the most comprehensive protection by stopping water before it reaches your foundation. Interior waterproofing is less expensive and works well for managing minor seepage or when exterior work isn’t practical. Many homes benefit from a combination approach—exterior work where possible and interior systems as backup. We’ll assess your situation and recommend the most effective solution for your specific water issues and budget.

What's the difference between waterproofing and just sealing basement walls?

Basement wall sealer is just one component of proper waterproofing. Sealing walls can help with minor moisture issues, but it won’t stop water that’s coming through foundation cracks, floor joints, or from hydrostatic pressure. True basement waterproofing addresses the entire water management system around your foundation—drainage, crack repair, moisture barriers, and often interior drainage systems. If you’re dealing with actual water intrusion rather than just dampness, sealing alone won’t solve the problem long-term.

How much does basement waterproofing cost in Merrick?

Basement waterproofing costs vary significantly based on your home’s specific needs. Interior waterproofing might range from $3,000-$8,000 for an average basement, while exterior waterproofing can cost $8,000-$15,000 or more depending on excavation requirements and drainage work needed. The investment typically pays for itself through prevented water damage, increased usable space, and higher home value. We provide detailed estimates after assessing your specific situation because every basement waterproofing project has different requirements.

Can you waterproof basements during winter in New York?

Interior basement waterproofing can be done year-round regardless of weather conditions. Exterior basement waterproofing is more challenging during winter due to frozen ground and excavation difficulties, but emergency repairs can often be completed when necessary. The best time for exterior work is late spring through early fall when ground conditions are optimal. However, if you’re dealing with active water intrusion, we can often implement interior solutions immediately to protect your basement while planning more comprehensive exterior work for better weather.

How do I know if my basement waterproofing is failing?

Signs of failing basement waterproofing include water stains on walls, musty odors, visible mold or mildew, efflorescence (white chalky deposits on walls), and actual water intrusion during heavy rains. You might also notice increased humidity levels, peeling paint on basement walls, or rust on metal items stored in your basement. If your basement was previously waterproofed but you’re seeing any of these signs, the system may need repair or replacement. Early intervention prevents more extensive water damage and more expensive repairs later.

Local Resources