Greenwich, CT · Fairfield County · Since 1994
Basement Waterproofing in Greenwich, CT.
Interior drainage built for two Greenwiches: coastal slab joints in Old Greenwich, Riverside, and Belle Haven where Long Island Sound holds the water table close to grade, and Backcountry estate foundations where shallow bedrock perches groundwater against pre-1940 fieldstone walls. Lifetime warranty in writing, transferable when you sell.
Free coastal-zone + estate-foundation inspection. Written estimate within 24 hours. Most jobs handled from inside – no exterior excavation across coastal hardscape or Backcountry landscaping.
- Lifetime waterproofing warranty
- Transferable on home sale
- Most jobs done in 1–3 days
Three Greenwich-specific waterproofing triggers
Coastal village or Backcountry estate – the signs are different. The fix is the same.
Greenwich’s housing stock spans pre-1900 fieldstone foundations in the Backcountry and Old Greenwich village core, mid-century block in Glenville and Byram, and modern poured concrete in Cos Cob and Riverside. The water-entry signature changes with the era and the elevation.
Storm-driven seepage after coastal nor’easters
Belle Haven, Mead Point, Riverside, and Old Greenwich properties sitting near the Long Island Sound shoreline see water pool against the foundation during nor’easters and tropical-remnant storms. If the slab joint shows a damp line within 48 hours of the storm, hydrostatic pressure is finding a path through.
SCHEDULE A FREE ESTIMATEYear-round musty air in Backcountry estates
On older Backcountry stone-foundation homes north of the Merritt Parkway, perched groundwater on shallow bedrock keeps the wall face damp for months at a time. The smell shows up in the floors above before the water does. That is the moisture loading you can see at the wall-floor joint with a flashlight.
SCHEDULE A FREE ESTIMATEEfflorescence on village fieldstone and block
White chalky residue across Old Greenwich and Cos Cob fieldstone walls or on Byram and Glenville cinder-block stock. The salt is the symptom, not the problem – water is moving through the masonry every freeze-thaw cycle. Visible most often after the spring melt.
SCHEDULE A FREE ESTIMATEBuilt for Greenwich, CT
What makes Greenwich basements different.
Waterproofing in Greenwich is shaped by the Mianus River and the tidal Long Island Sound shoreline. In Belle Haven and Old Greenwich, the combination of shallow bedrock and glacial till in the backcountry, with coastal silt and clay closer to the shore keeps the water table high enough to push hydrostatic pressure through any unprotected slab joint. That is why interior drainage outperforms exterior excavation on the housing stock here: pre-1940 estate properties in Belle Haven and Mead Point, mid-century homes in Riverside, and stone-foundation colonials in the backcountry. The drain tile sits above the footing, daylights into a sealed sump, and discharges below frost. The wall and slab stay structurally intact.
- ZIP coverage. Service covers Greenwich ZIPs 06830, 06831, 06836, 06870, 06878, and 06807.
- Adjacent towns. We also serve nearby Stamford, Port Chester (NY), and Rye.
- Frost depth. Footings on every job we run extend below the 42-inch frost line required by the Connecticut State Building Code.
Greenwich-specific questions
Greenwich basement waterproofing – the questions we get most.
Do you handle waterproofing on coastal Greenwich properties in FEMA flood zones?
Yes. Belle Haven, Mead Point, Old Greenwich, and Riverside addresses commonly sit in FEMA AE or VE coastal flood zones. Interior drainage is permitted as basement-moisture management regardless of flood-zone designation; we coordinate the Greenwich Building Department paperwork and any historic-district considerations end-to-end.
Will exterior excavation damage estate landscaping in the Backcountry?
We avoid exterior excavation on roughly 85 to 90 percent of Greenwich jobs by using an interior drainage approach. The drain tile sits above the footing inside the basement, daylights into a sealed sump, and discharges below the 42-inch CT frost line. Backcountry landscaping, stone walls, and coastal hardscape stay untouched.
How does Greenwich’s coastal humidity affect basement waterproofing?
Long Island Sound keeps Fairfield County’s relative humidity high through the warm months, especially in shoreline villages. Waterproofing only solves liquid-water intrusion; vapor barrier and dehumidification handle the airborne side. We spec both together on coastal Greenwich properties so the basement does not run damp in July even when no water is entering.
Is a permit required for waterproofing in Greenwich?
Permit requirements vary by project scope. The Town of Greenwich Building Department reviews interior drainage and sump installations; historic-district properties in Old Greenwich and Cos Cob may have additional preservation considerations. We coordinate the permit and inspection paperwork end-to-end so you are not chasing town hall.
Why CT and NY homeowners pick Big Easy for waterproofing.
How we actually do it
Interior drainage. Not exterior excavation.
The waterproofing industry has a dirty secret: the most profitable job is also the most invasive one. Excavating your yard, exposing the foundation from outside, applying a membrane, backfilling. $25,000 to $40,000 typical. Disrupts your landscaping for weeks.
The cleaner truth: for the vast majority of CT and NY basements, an interior drainage system solves the same problem – permanently – for a fraction of the cost, with zero impact on your yard. Here is exactly how we do it.
Free inspection
A specialist examines every foundation wall, every existing drain, every moisture sign. We document with photos and measurements. You get a written estimate within 24 hours – no high-pressure follow-up.
Cut perimeter trench
We carefully saw-cut a 4-to-6-inch-wide trench around the interior perimeter where the foundation wall meets the slab – right above the existing footing. Dust controlled at the source. No demolition outside this strip.
Install drain + sump system
Perforated PVC drainpipe laid in clean stone, pitched toward a sump basin we install in the corner. Battery backup pump included as standard. Discharge line routed outside, below the 42 inches CT frost depth so it never freezes shut.
Vapor barrier + restore slab
Wall vapor barrier installed and sealed to the new drain. Concrete poured back over the trench, finished smooth. The basement looks essentially the same as when we arrived – only now it stays dry, with a lifetime warranty in writing.
When exterior excavation IS the right call
We tell you straight: about 10–15% of jobs genuinely need exterior excavation. Severe foundation cracks under hydrostatic load. Failed exterior membrane on a relatively new home. Certain century-old fieldstone foundations. If that’s your situation, we’ll say so on the free inspection. We won’t sell you interior drainage that won’t solve the actual problem – and we won’t sell you exterior excavation that isn’t needed. That’s the difference.
Real waterproofing projects in CT and NY.
Illustrative example · representative of typical basement waterproofing work · not a specific Big Easy customer project[Problem solved in one sentence – e.g. “Recurring storm-driven seepage stopped, basement bone-dry through Hurricane season”]
Illustrative example · representative of typical basement waterproofing work · not a specific Big Easy customer project
Illustrative example · representative of typical basement waterproofing work · not a specific Big Easy customer project[Problem solved in one sentence – e.g. “Pre-listing moisture mitigation completed, inspector signed off in time for closing”]
Illustrative example · representative of typical basement waterproofing work · not a specific Big Easy customer project
Free waterproofing inspection. Written estimate within 24 hours.
Sixty minutes on site. No verbal guesses. No high-pressure follow-up. An honest answer about whether you need interior drainage – or whether your specific situation is one of the rare cases that genuinely needs exterior work.
- Full foundation walk-through
- Photo documentation of every moisture sign
- Written estimate emailed within 24 hours
- Lifetime warranty in writing, transferable on home sale
- Honest answer if exterior excavation is necessary – or isn’t
Book your free inspection
No obligation. Written estimate within 24 hours.
Tell us what is happening with your basement and we will email a written estimate within 24 hours. No cost, no obligation, no high-pressure follow-up.
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