Licensed Waterproofing specialists serving Great Neck, NY with written warranties on every job, residential and commercial alike.

SGP Waterproofing is a licensed and insured Waterproofing contractor serving homeowners, property managers, and commercial building owners across Great Neck, NY. We didn't start as a marketing company that added waterproofing to a service list — our crews came up running sump pumps, pouring interior drain tile, and injecting epoxy into foundation cracks long before the trucks had our name on the door.
We keep our crews local rather than routing calls through a national call center, which means the technician who answers your questions on the phone is often the same person standing in your basement two hours later. That continuity cuts down on the miscommunication that drags out so many waterproofing jobs.
Freeze-thaw cycles, seasonal rainfall patterns, and water table depth all shift how urgently a given crack or seep needs attention in Great Neck, NY specifically. We track these patterns because they change how we prioritize scheduling during storm season versus a slow drip in the middle of a dry month.
Because we've worked enough Great Neck, NY basements to recognize patterns, we can often tell within the first ten minutes of an inspection whether a problem is isolated or connected to a larger drainage issue affecting the whole block. That context shapes whether we recommend a small crack repair or a full interior system.

Water damage rarely announces itself with a flooded basement on day one. It usually shows up as one of these smaller signals first, and Great Neck, NY's seasonal moisture swings tend to speed the timeline up.
A persistent musty smell almost always means moisture is present somewhere in the wall assembly, even if you can't see a wet spot yet.
Efflorescence forms when water carries dissolved minerals through porous concrete and leaves them on the surface as it dries — a clear sign moisture is actively passing through.
A crack that's a sixteenth of an inch wide today can become a sixteenth of an inch wider by next spring if the pressure behind the wall isn't relieved.
Drywall that feels soft, bubbles, or shows a tide line near the floor is already absorbing groundwater — by the time you see it, the insulation behind it is usually soaked too.
A window well that fills with water during heavy rain is putting direct pressure on the glass and frame, and it's one of the most common entry points we find in older Great Neck, NY homes.
Puddling near the foundation that doesn't drain within a few hours usually means grading, gutters, or a failing perimeter drain — and it's the fastest path to a flooded basement.
Every job starts with the same on-site inspection, whether it's a single crack or a full interior drainage retrofit. Below are the services Great Neck, NY clients request most often.
Once the water is out, we run air movers and dehumidifiers to bring humidity down before mold has a chance to establish itself in drywall or subfloor.
For finished basements we route the drain tile beneath the existing slab edge, which limits how much flooring has to come up during installation.
Commercial jobs typically pair exterior membrane work with an interior collection system, since most existing commercial structures can't be fully excavated without major disruption.
Low-pressure epoxy injection bonds structural cracks back together, while polyurethane injection is better suited for cracks that are still actively leaking.
A properly encapsulated crawl space with its own sump discharge line keeps humidity below the threshold where wood rot and mold can take hold.
Sometimes the fix isn't inside the wall at all — regrading the soil away from the foundation and adding a French drain can solve a moisture problem before water ever reaches the block.
You describe what you're seeing and we ask a few questions to gauge urgency before anyone gets in a truck.
We walk the interior and exterior with a moisture meter and flashlight, tracing water back to its actual entry point instead of guessing.
You get a flat-rate, itemized quote before any work starts — no verbal estimate that changes once the crew shows up.
Once installation wraps, we test the sump pump under load and walk you through the warranty paperwork before we leave the site.
You'll know the total cost before we start — no hourly billing, no surprise add-ons once the walls are already open.
Because our crews are based in and around Great Neck, NY, we're not routing your call through a national scheduling system that books you two weeks out.
Our crews run truck-mounted extraction units, moisture meters, and thermal imaging cameras — not a shop-vac and a guess.
If a sealed crack reopens or a sump system underperforms within the warranty window, we come back and make it right at no extra charge.

We document every job with photos, moisture readings, and a copy of the warranty terms, so there's a paper trail if you ever need to reference the work again.


Our Great Neck coverage area extends through most of the surrounding Great Neck, NY communities. Give us a call even if your address falls just outside the zone below; we'll let you know honestly if we can reach you same-day.

Zip codes we serve in Great Neck, NY: 11024 11023 11027 11020 11021

"Our basement flooded during a storm at 2am and someone actually picked up the phone. The crew had pumps running before sunrise and came back two days later to install the drain tile system."
— Great Neck Homeowner
"The crack in our basement wall had been leaking for a year before we finally called. Injection took less than an afternoon and it's been dry since."
— Great Neck Seller
"Our crawl space had standing water and a mold smell we couldn't get rid of. They pumped it out, encapsulated the whole thing, and added a dedicated sump discharge line."
— Great Neck Homeowner
"Our old sump pump died during the biggest storm of the year and we got water in the finished basement. They replaced it with a battery backup system so we're covered even during a power outage."
— Great Neck Customer
"Our parking garage had a persistent leak coming through the deck above the lower level. They installed a membrane system and coordinated the work around tenant parking so nobody was displaced."
— Great Neck Property Manager
"We'd been dealing with musty smell in the basement for years and finally found out it was efflorescence building up behind the paint. Interior drain tile solved it for good."
— Great Neck Homeowner
Response time depends on call volume and severity, but emergency water intrusion always jumps the queue ahead of routine estimates.
Pricing is disclosed in full before you sign anything, and we walk through each line item so nothing is a surprise later.
Emergency crews are equipped to stabilize the situation immediately, then schedule the permanent fix once the immediate flooding risk is under control.
Cost depends on square footage, the type of system needed, and whether the fix is interior drainage, exterior membrane work, or both — we won't quote a number without an in-person inspection first.
No crack is too small to inspect; catching it early usually means a smaller repair bill down the road.
We install both — interior drain tile and sump systems for most residential jobs, and exterior membrane or French drain systems when the source is surface water or when excavation is practical.
A single crack injection can be done in an afternoon, while a full interior drainage system typically runs two to three days start to finish.
We're happy to provide the documentation adjusters typically request, though we recommend confirming your specific coverage details directly with your insurance provider.
A French drain without a sump pump just relocates water to one spot; the pump is what actually discharges it away from the home.
Yes, every interior drainage, sump, and crack repair job comes with a written warranty, and terms are explained in full before you approve the quote.
Standing water doesn't stop us from starting; we extract it as the first step, then proceed with vapor barrier and drainage installation.
Yes — our commercial work covers parking garages, retail basements, and multi-family buildings, usually scheduled in phases to minimize tenant disruption.
Call now for a free inspection and a flat-rate quote before anything gets worse.
Call +1-866-476-1348© SGP Waterproofing. All rights reserved.