Waterproofing and Foundation Repair Services in NJ & Eastern PA
Waterproofing and foundation repair services should be matched to the actual cause of the problem. Down Under Waterproofing serves homeowners and property owners throughout New Jersey and Eastern Pennsylvania with solutions for basement water, foundation movement, drainage issues, crawl space moisture, concrete and masonry deterioration, structural damage, and exterior water intrusion.
Since 2006, our team has focused on identifying the source of the problem first and then recommending the right repair for the property’s actual conditions. Many water and structural problems are connected, which is why our services include waterproofing, drainage, foundation repair, masonry, concrete, structural stabilization, and restoration.
Based in Robbinsville, NJ, we are a service-area contractor serving New Jersey and Eastern Pennsylvania. We travel directly to customers and do not operate a public storefront or showroom.
Direct Answers About Our Waterproofing and Foundation Repair Services
What services do you provide?
We provide Basement Waterproofing, Foundation Repair, crawl space encapsulation, French drains, sump pump systems, exterior drainage, concrete and masonry repair, retaining walls, stucco repair, above-grade waterproofing, Bilco doors, structural restoration, and related services.
Do you provide concrete work?
Yes. Our concrete work may include concrete repairs, steps, walkways, exterior slabs, foundation concrete, retaining wall repairs, and concrete affected by cracking, settlement, deterioration, or water-related damage.
Do you install French drains and sump pumps?
Yes. We install interior French drains, sump pump systems, battery backup options, and related basement drainage components based on the property’s water conditions.
Can one project require several services?
Yes. Basement seepage, foundation cracks, poor drainage, damaged masonry, rotted framing, and structural movement can occur together. Some projects require a coordinated repair plan.
Waterproofing and Foundation Repair Services We Provide
Down Under Waterproofing provides a broad range of waterproofing, drainage, foundation, concrete, masonry, structural, and exterior repair services. The appropriate service depends on where water is entering, how the structure is responding, and what conditions are contributing to the damage.
Basement Waterproofing
Interior and exterior waterproofing for wet basements, wall seepage, floor leaks, cove-joint water entry, foundation cracks, and hydrostatic pressure.
Explore Basement Waterproofing →French Drains
Interior drainage systems designed to collect groundwater, relieve pressure around foundations, and direct water toward a sump pump system.
View French Drain Services →Sump Pumps & Battery Backup
Liberty sump pump systems, replacement pumps, battery backup options, discharge evaluation, and integration with basement drainage systems.
Learn About Sump Pump Systems →Crawl Space Encapsulation
Vapor barriers, drainage, sump systems, dehumidification, humidity control, and crawl space moisture protection.
Learn About Crawl Space Encapsulation →Recent Hamilton Drainage & Encapsulation Project →
Foundation Repair
Foundation crack repair, bowed wall stabilization, carbon fiber systems, structural wall repair, settlement concerns, and related stabilization.
View Foundation Repair Services →Underpinning & Structural Stabilization
Structural support and stabilization for qualifying foundation conditions, including engineer-coordinated work when plans, permits, or inspections are required.
Explore Basement Underpinning & Foundation Stabilization →Masonry & Concrete Repair
Brick, block, stone, mortar, foundation concrete, concrete walls, exterior surfaces, and repairs related to cracking, movement, water damage, or deterioration.
View Masonry & Concrete Repair →Concrete Steps, Walkways & Exterior Concrete
Concrete steps, walkways, patios, exterior slabs, cracked concrete, deterioration, settlement-related repairs, and replacement where appropriate.
Explore Concrete Services →Construction & Structural Restoration
Sill plates, joists, beams, LVLs, support columns, subfloor repairs, sagging floors, and structural wood damaged by moisture or deterioration.
Explore Construction Restoration →Retaining Walls
Repair and support for masonry and concrete retaining walls, soil pressure, wall movement, drainage issues, cracking, and deterioration.
View Retaining Wall Services →Stucco & EIFS Repair
Stucco cracks, EIFS damage, exterior wall moisture, failed sealants, damaged finishes, and related water-intrusion repairs.
Review Stucco Repair Options →Above-Grade Waterproofing
Exterior wall leaks, windows, doors, flashing, caulking, sealants, coatings, penetrations, masonry, stucco, and building-envelope water intrusion.
Explore Above-Grade Waterproofing →Bilco Doors & Basement Entryways
Bilco door replacement, basement entryway repairs, thresholds, egress windows, window wells, and water-entry correction around exterior openings.
View Basement Entry Services →Exterior Drainage & Dry Wells
Downspout extensions, underground drainage, dry wells, surface-water management, sump discharge, and drainage improvements near foundations.
Explore Drainage Solutions →Why Waterproofing and Foundation Repair Services Start With Diagnosis
A wet basement, cracked foundation, damp crawl space, damaged concrete, failing masonry wall, leaking exterior wall, sagging floor, or moving retaining wall is often a symptom rather than the entire problem.
Water may be collecting around the foundation. Soil pressure may be pushing against a wall. Drainage may be directing water toward the home. Moisture may have damaged wood framing or masonry over time. That is why our waterproofing and foundation repair services begin with identifying the actual cause.
Proper moisture control starts with understanding how water moves through and around a building. Homeowners can also review the U.S. Environmental Protection Agency’s moisture-control guidance for general information about preventing moisture-related building problems.
Water Source
We evaluate groundwater, runoff, grading, drainage, foundation seepage, exterior openings, sump discharge, crawl space moisture, and related water paths.
Structural Condition
We look for cracks, bowed walls, settlement signs, concrete deterioration, damaged masonry, rotted framing, sagging floors, and retaining wall movement.
Long-Term Solution
We determine whether the property needs waterproofing, drainage, structural repair, masonry, concrete work, restoration, or a combination of services.
Common Problems We Help Solve
Wet Basement
Basement seepage, wall leaks, floor water, hydrostatic pressure, drainage problems, and recurring water after storms.
Foundation Cracks & Bowing
Vertical cracks, horizontal cracks, stair-step cracking, wall movement, bowed walls, settlement concerns, and structural pressure.
Damp Crawl Space
Ground moisture, humidity, odors, condensation, damaged insulation, wood deterioration, and crawl space water.
Damaged Concrete & Masonry
Cracked concrete, damaged steps, deteriorated mortar, brick or block movement, freeze-thaw damage, and moisture deterioration.
Sagging Floors & Rotted Wood
Damaged joists, sill plates, beams, support columns, subfloors, and structural wood affected by moisture.
Exterior Water Intrusion
Water entering around stucco, masonry, windows, doors, flashing, caulking, retaining walls, or exterior wall systems.
Why Homeowners Choose Down Under Waterproofing
Serving NJ & Eastern PA Since 2006
Serving New Jersey and Eastern PA since 2006 with experience in waterproofing, foundation, drainage, masonry, concrete, crawl space, and structural repairs.
Diagnosis Before Repair
We evaluate the source of the problem before recommending a waterproofing, drainage, foundation, structural, concrete, or masonry solution.
Licensed, Insured & Bonded
NJ License #: 13VH03267600
PA License #: PA175894
Bonding #: 72695582
Engineering When Required
Structural projects may include engineer coordination, permits, engineered repair plans, and inspections where required.
Waterproofing Warranty
Qualifying waterproofed areas carry a lifetime transferable warranty, provided the waterproofing system is not altered or tampered with and subject to the written warranty terms.
Manufacturer Warranties
Applicable manufacturer warranties are also provided for eligible pumps, waterproofing products, structural systems, and installed components.
Financing Options for Qualifying Home Improvement Projects
Waterproofing, foundation, crawl space, drainage, masonry, and structural repairs do not always happen when the expense fits comfortably into the household budget. Down Under Waterproofing offers access to financing options through Hearth for qualifying home improvement projects.
Financing is optional and separate from your free project estimate. Explore Project Financing Options →
Waterproofing and Foundation Repair Services Across NJ & Eastern PA
Down Under Waterproofing provides waterproofing, foundation repair, concrete, masonry, drainage, crawl space, structural restoration, and related services throughout our New Jersey and Eastern Pennsylvania service areas.
Primary New Jersey Service Area
Mercer, Monmouth, Middlesex, Somerset, Hunterdon, Morris, and Ocean counties.
Select North Jersey Projects
Qualifying projects may also be considered in Bergen, Essex, Hudson, and Union counties depending on project location, scope, scheduling, and travel requirements. We are not currently scheduling projects in Newark or Elizabeth.
Eastern Pennsylvania
Regular service includes Bucks County, Montgomery County, and Philadelphia, PA.
Mercer County NJ | Monmouth County NJ | Middlesex County NJ | Somerset County NJ | Hunterdon County NJ | Morris County NJ | Ocean County NJ | Bucks County PA | Montgomery County PA | Philadelphia, PA
Request a Free Estimate
Tell us what you are seeing — basement water, foundation cracks, crawl space moisture, drainage problems, masonry or concrete damage, exterior leaks, retaining wall concerns, or structural damage.
Need payment flexibility? Financing options are available through Hearth for qualifying home improvement projects. Review project financing options →
Helpful Waterproofing & Foundation Repair Resources
Ultimate Guide to Basement Waterproofing
Learn how water enters basements, how drainage systems work, and how waterproofing systems are designed.
Read the Waterproofing Guide →Foundation Repair Warning Signs
Review cracks, wall movement, uneven floors, sticking doors, and other signs of structural movement.
Review Foundation Warning Signs →French Drain vs. Sump Pump
Understand the difference between collecting groundwater and pumping it safely away from the basement.
Compare French Drains and Sump Pumps →Basement Waterproofing Resources
Browse homeowner guides covering basement water, foundations, crawl spaces, drainage, waterproofing systems, and repair options.
View All Resources →Frequently Asked Questions About Our Services
Technical content reviewed by Walter Gural Jr., owner of Down Under Waterproofing, a licensed New Jersey and Pennsylvania home improvement contractor with experience in basement waterproofing, foundation repair, drainage, crawl space encapsulation, masonry, concrete, structural stabilization, and restoration.
Last updated: August 2026.
Whether your property has basement water, foundation cracks, crawl space moisture, drainage problems, damaged concrete, deteriorated masonry, sagging floors, exterior wall leaks, retaining wall movement, or structural damage, the right repair starts with identifying the source.
Schedule a Free Waterproofing or Foundation Repair Estimate
If you are dealing with water intrusion, foundation movement, crawl space moisture, drainage problems, concrete or masonry damage, retaining wall concerns, exterior leaks, or structural deterioration, contact Down Under Waterproofing for an evaluation.
Licensed & Insured | NJ #13VH03267600 | PA #PA175894 | Bonding #72695582 | Monday through Saturday, 7:00 AM to 7:00 PM