California Subterranean Waterproofing Solutions
Protecting Structures From the Ground Up
Water is one of the most persistent threats to below-grade construction. When groundwater, hydrostatic pressure, or migrating moisture reaches foundations, slabs, and basement walls, it can result in structural deterioration, mold growth, interior damage, and costly project delays. Subterranean waterproofing provides the critical barrier between your structure and immense headaches.
At Advanced Construction Technology, a FullTerra company, our family of environmental mitigation companies brings decades of experience designing, installing, and monitoring below-grade protection systems in California. Whether you’re developing a new commercial property, remediating a brownfield site, or addressing water intrusion on an existing structure, we deliver solutions engineered for long-term durability.
Why Subterranean Waterproofing Matters
Below-grade structures face constant exposure to moisture from surrounding soil and groundwater. Without proper waterproofing, that moisture can compromise the integrity of foundations, damage interior finishes, create hazardous mold conditions, and undermine the property’s long-term value.
Subterranean waterproofing is especially critical on sites with high water tables, expansive soils, or known contamination — conditions where moisture management intersects directly with environmental mitigation. On many of the projects we serve, waterproofing works hand-in-hand with vapor barriers, commercial radon monitoring & mitigation, and methane mitigation systems to create a comprehensive envelope of protection beneath the structure.
When to Consider Subterranean Waterproofing
Waterproofing should be evaluated at multiple stages of a project’s lifecycle:
- Pre-Construction: During site analysis and design, particularly on sites with elevated water tables, poor drainage, or historical contamination.
- New Construction: As part of the foundation and below-grade envelope design for any structure with occupied or conditioned space below grade.
- Existing Structures: When water intrusion, efflorescence, or moisture-related damage is observed in basements, parking structures, or mechanical rooms.
- Brownfield Redevelopment: Where waterproofing must be integrated with vapor intrusion barriers and environmental remediation systems.
Near Sensitive Environments: Schools, hospitals, data centers, and other facilities where moisture control is essential to operations and occupant safety.
Our Subterranean Waterproofing Services
Below-Grade Membrane and Barrier Systems
We design and install high-performance waterproofing membranes that work best for your site conditions and structural requirements. These barriers are applied to foundation walls, slabs, and below-grade joints to prevent water penetration at every vulnerable point.
On contaminated sites, our membrane systems can be integrated with vapor barriers and chemical-resistant liners, providing dual protection against both moisture and hazardous vapor intrusion.
Drainage and Water Management Systems
Effective waterproofing goes beyond barriers. We engineer complete drainage solutions, including perimeter drain systems, sump pump installations, and cavity drain membranes to manage hydrostatic pressure and redirect water away from the structure. These systems are especially important in areas with fluctuating water tables or heavy seasonal rainfall.
Waterproof Concrete and Integral Systems
For projects where applied membranes aren’t practical or where redundancy is required, we consult on and specify integral waterproofing solutions. These include crystalline admixtures and hydrophilic waterstops that make the concrete itself the primary line of defense against moisture penetration.
Monitoring and Maintenance
Waterproofing systems require ongoing oversight to perform at their best. We provide post-installation inspections, leak detection, and long-term monitoring — leveraging the same telemetry and data-driven approach we use across our environmental mitigation projects.
How Waterproofing Connects to Environmental Mitigation
On many of the sites we serve, water management and environmental protection are inseparable. Contaminated groundwater can carry volatile organic compounds (VOCs) into below-grade spaces. Methane and other soil gases often follow the same migration pathways as moisture. A waterproofing failure can also create a pathway for hazardous vapors.
That’s why our approach treats waterproofing as part of a unified below-grade protection strategy. When you work with FullTerra, your waterproofing system is designed to complement your vapor barriers, methane mitigation systems, and ongoing environmental monitoring as an integrated solution.
Who We Serve
- Developers and General Contractors building new residential, commercial, and mixed-use projects
- Property Owners and Facility Managers addressing water intrusion in existing structures
- Environmental Consultants seeking a design-build partner for sites with combined moisture and contamination challenges
Industrial and Institutional Clients: including schools, hospitals, government buildings, aerospace and defense facilities, and logistics centers
Part of the FullTerra Family
Subterranean waterproofing is delivered through the FullTerra network — the nationwide leader in environmental mitigation services. Together with our sister companies, we provide comprehensive design-build-monitor solutions that protect properties and people across all 50 states.
Our combined expertise means your waterproofing project benefits from the same engineering rigor, field experience, and regulatory knowledge that has protected over 70 million square feet of construction nationwide.
Complex Sites Require Sophisticated Solutions
No two sites present the same waterproofing challenge. Soil conditions, water table depth, structural design, and environmental factors all influence the right approach. Tell us about your project, and we’ll help you evaluate your site, identify risks, and implement a waterproofing system built to last.
Complex sites require sophisticated solutions.
Join developers and property owners nationwide who trust us with their most challenging environmental projects.