"Water does not announce itself. By the time you see the damage, it has been working for months. We stop it before it starts."
Balcony, terrace, deck, and below-grade waterproofing in Brooklyn, Queens, and Manhattan. Liquid-applied membranes, sheet waterproofing, crystalline systems, and drain board assemblies. We have waterproofed luxury high-rises in Williamsburg and basement walls in Bay Ridge. Same standard of care on every job.
Waterproofing is the process of applying specialized membranes, coatings, and sealants to surfaces that are exposed to water — preventing moisture from penetrating walls, roofs, and foundations. In Brooklyn, where buildings range from century-old brownstones to modern apartment blocks, waterproofing is not optional. It is essential maintenance.
Water infiltration is the #1 cause of structural damage in New York City buildings. A small crack or failed membrane allows water to seep in, freeze in winter, expand, and cause cracks to grow. Over time, this leads to mold, rot, compromised foundations, and expensive structural repairs that can cost tens of thousands of dollars.
The good news: professional waterproofing applied correctly lasts 10–25 years and pays for itself many times over by preventing damage. MLM Construction Group uses premium-grade materials including EPDM membranes, TPO systems, crystalline waterproofing compounds, and liquid-applied coatings tailored to each surface type.
We apply high-performance membranes — EPDM, TPO, liquid-applied coatings, and modified bitumen — directly over flat and low-slope roofs. Our roof waterproofing systems are backed by manufacturer warranties and protect against ponding water, UV degradation, and freeze-thaw damage common in NYC winters.
Brooklyn basements face constant hydrostatic pressure from groundwater. We install interior drainage systems, apply crystalline waterproofing compounds to block walls, seal floor-wall joints, and where needed, install sump pump systems. The result: a dry, livable basement that stays dry year-round.
Foundation cracks are a gateway for water, mold, and structural failure. We excavate where necessary, apply elastomeric coatings and drainage boards to foundation walls, and install French drain systems to redirect water away from your building. Essential for older Brooklyn homes and brownstones.
Brick facades, stucco walls, and concrete surfaces all absorb water over time. We apply penetrating sealers and elastomeric coatings that repel water while allowing the wall to breathe — critical for Brooklyn's brownstones and older masonry buildings to prevent spalling and freeze damage.
Roof terraces and balconies are among the most vulnerable areas of any Brooklyn building. We install liquid-applied waterproofing systems with fabric reinforcement, sloped drainage, and UV-resistant topcoats that keep your terrace watertight and usable for decades.
Parapet walls sit at the top of flat-roofed buildings and take the full brunt of Brooklyn weather. Cracked or failed parapet capping allows water to travel directly into the roof assembly and walls below. We cap, seal, and waterproof parapet walls to stop this common source of leaks.
We assess every vulnerable surface — roof, walls, foundation — and identify all existing leaks and at-risk areas.
You receive a clear written estimate with the exact materials, methods, and warranty for your specific project.
Our licensed crew applies premium waterproofing systems following manufacturer specs and NYC DOB codes.
We provide written warranty documentation and check in after the first heavy rain to confirm performance.
Every day without proper waterproofing is another day water gets deeper into your walls and foundation. Call MLM Construction Group today for a free inspection and estimate.