New Construction Foundation Waterproofing Methods

New Construction Foundation Waterproofing Methods

Residential
Carrie Powers
Carrie Powers
February 19, 2025
6 min
Share

High-performing new construction foundation waterproofing provides the most economical and efficient method for preventing below-grade water infiltration and ensuring a strong, durable, and safe building. Waterproofing can also offer insulation and reduce insect problems. Designing a foundation without adequate waterproofing can lead to cracked walls, uneven floors, potential structural collapse, and costly and complicated repairs.

A building's long-term integrity depends on quality new construction foundation waterproofing methods that protect against water and vapor infiltration into the concrete by hydrostatic pressures and capillary action.
 

Fortunately, Polyguard waterproofing products will protect against hydrostatic pressures and capillary action. As a result, our products ensure protection against moisture and air infiltration in the most severe conditions, which can significantly contribute to a building's long-term integrity, health, and safety.
 

Vital New Construction Foundation Waterproofing Methods
 

Adequately waterproofing a foundation during new construction involves strategies to prevent below-grade liquid and vapor water infiltration due to hydrostatic pressure and capillary action.

Hydrostatic pressure happens when gravity pushes static (stagnant-dense) water (hydro) against below-grade walls built entirely or partially on a hillside or below the water table. Hydro pressure rises with depth and soil wetness. Hydrostatic pressure on foundation walls causes moisture to infiltrate through joints and cracks, which permeates solid concrete through capillary action (wicking).

Capillary action refers to water’s ability to flow into narrow channels between porous building products, like concrete, which act like tubes due to cohesive and adhesive forces interacting between the surface and liquid without the assistance of gravity.

For reference, the 2021 International Residential Code (IRC) (Section R406) and the 2021 International Building Code (IBC) (Section 1805) specify the conditions that require either waterproofing or damp proofing foundations.

 

Drainage Methods Protect Foundation from Hydrostatic Pressure
 

Hydrostatic pressure prevents water infiltration to the foundation and requires adequate drainage that eliminates water pressure against the foundation's floor or walls. 
 

Backfill
 

Backfilling with at least 16 inches of granular material next to the foundation wall will keep water away from the wall, to prevent leaks through cracks. Water that gets this far should drain freely to the footing drains. The backfill should slope about 10 feet away from the foundation in order to remove water away from the foundation quickly.

Footing Drains
 

Gutters and grading provide the first line of defense against a wet foundation. However, the foundation waterproofing methods must also include footing drains to keep the below-grade walls dry.

New construction foundation waterproofing must include perforated drain piping around the foundation’s perimeter (footing drains) to direct water away from the footings. Typically, residential builders place the drain pipe a couple of inches below the footing’s top and at least 6-inches below the slab’s top.
 

Preventing Capillary Action When Waterproofing Foundation
 

Even with good surface water drainage management, soil still contains a high level of water vapor that can migrate into a building through the foundation walls by capillary action.

A white powdery substance on the foundation's interior wall indicates a problem with capillary action. As moisture passes through concrete, it dissolves salts, and carries them to the foundation's floors or walls, leaving behind white efflorescence (salt deposits) when the water dissolves.

Methods for waterproofing a new construction foundation against capillary action include: 
 

Dampproofing
 

Dampproofing involves spraying or rolling a coating onto the outside of the wall. A dampproofing barrier prevents water from the soil seeping into the permeable foundation. In addition, adding dampproofing to the concrete mix will make the concrete water-resistant.

However, dampproofing does not stop liquid water or bridge the tiny shrinkage gaps between a floor slab and the foundation wall. Thick and flexible waterproof coatings can bridge these gaps and prevent water from accumulating around the base of the foundation, by exerting hydrostatic pressure against the walls.
 

Vapor Barrier
 

Installing a vapor barrier on a foundation will stop vapor and liquid water in the soil from passing through the foundation and into the building through capillary action.

Capillary Break
 

Capillary breaks (physical gap) can help stop capillary transmission of water from the soil to a concrete foundation. You can create a capillary break with a waterproof membrane material, a granular fill layer (crushed stone or gravel), or a manufactured drainage membrane against the foundation wall.
 

Polyguard Offers the Best New Construction Foundation Waterproofing Methods
 

Polyguard's new construction foundation waterproofing methods protect, in the harshest conditions, against liquid and vapor water infiltration into the concrete foundation or slab by hydrostatic pressures and capillary action. Our products include sheet and fluid applied products and drainage systems
 

Polyguard Below-Grade Sheet Membranes
 

UNDERSLAB MEMBRANE
 

Tough, 85-mil Underslab Membrane vapor barrier/waterproofing membrane installs horizontally over prepared sub-bases like mud slab, compacted soil, carton forms, or #57 stone, and stops vapor and water transmission through concrete slabs.

During the concrete pour, the concrete blends with the fibers of the nonwoven geotextile in order to create a tough and secure mechanical bond with the membrane.

Builders can also install Underslab Membrane vertically on removable formwork for waterproof protection for elevator pits, perimeter, and grade beam installations, or against adjoining buildings to provide waterproofing protection.
 

BLINDSIDE MEMBRANE
 

Puncture-resistant, flexible, 73 mil Blindside Membrane waterproofing membrane applies in areas where soil retention does not permit access to the positive side (post applied). It installs vertically before pouring the concrete. As the concrete cures, it creates a mechanical bond with the membrane. The membrane's cold flow tendencies produce an outside adhesive layer for a tight seal and excellent protection against moisture, methane.

Builders can install the Blindside Membrane horizontally over prepared sub-base like Polyguard approved drainboard, carton forms, mud slab, carton, or fine crushed beds/pea gravel.
 

650 MEMBRANE
 

Flexible, strong, 60-mil 650 Sheet self-adhesive vapor retarder/waterproofing membrane prevents vapor and water transmissions through poured concrete foundation walls, CMU, insulated concrete forms (ICF), and wood. In addition, the 650 Membrane's design allows for use in vertical/secure wall and horizontal/split slab applications for vital waterproofing projects.

The Polyguard 650 Membrane comes in a wide membrane (up to 48-inches), to permit fast and simple application to continuous flat surfaces. However, we also offer it in a narrow width for construction joints, trimming corners, and other applications.

650 PRM Puncture Resistant Membrane
 

Self-healing, high-strength 65-mil 650 PRM is a post-concrete pour sheet vapor retarder/waterproofing membrane with a double-thick, cross-laminated polyethylene backing laminated to a thick layer of rubberized asphalt compound.

650 PRM adheres permanently and tightly to concrete. It's backing also creates a continuous barrier to water and moisture vapor infiltration.

Builders can apply 650 PRM vertically to concrete foundation walls, tunnels, and related applications, and for exterior sides needing waterproofing, it provides quicker application by removing the step of installing a protection course before backfilling operations.

Builders can also apply 650 PRM to horizontal slab applications like plaza decks, parking garages, plywood decks, and similar applications. In most situations, it also permits concrete topping slab installation without a separate protection course.
 

FLUID-APPLIED Below-Grade WATERPROOFING
 

Polyguard developed our fluid-applied single component Stretch Flex with our patented thermoplastic technology. It offers a spray, cold-applied (down to -20° F) product that creates a durable, seamless waterproofing membrane, bridges substrate shrinkage cracks up to 1/16-inch, eliminates problems at the joints, and minimizes surface breaches. We designed Stretch Flex for simple application to below-grade exterior waterproofing of precast concrete, concrete, CMU foundations, and other structural surfaces on the hydro-positive side.
 

Polyguard Offers The Best Drainage Options
 

The design of our high-capacity Polyflow® Drainage products provides builders with various solutions to lightweight drainage that is compatible with our engineered liquid and sheet membrane products. Our simple-to-install products lessen excavation needs, saving both time and money.
 

Polyflow® 15 and 15P SHEET MOLDED DRAINAGE MATS
 

Polyflow® 15 and 15P Sheet Molded Drainage Mats, applied vertically over Polyguard waterproofing membranes, direct moisture into the drain core while minimizing the movement of soil particles to prevent clogging of the core. When connected to our high capacity collector and outlet drainage system, Totalflow™, our Polyflow® 15 and 15P drainage mats can minimize hydrostatic pressure.
 

Polyflow® 18 DRAINAGE MAT
 

High-capacity Polyflow® 18 is a lightweight drainage system compatible with our engineered sheet and liquid membrane products for below-grade waterproofing.

Lightweight and simple to install, the Polyflow® 18 drainage mat offers a compressive strength of 21,000 psf. It can handle the most complex horizontal applications. In addition, this product uses a woven filter fabric specifically for concrete pours, allowing flow under loaded conditions.
 

Why Choose Polyguard Foundation Waterproofing Methods? 
 

A foundation's strength and durability significantly impact a building's longevity and performance. Extensive and costly problems to a building's integrity will occur from inadequate design and installation of the foundation's waterproofing and drainage systems.

To avoid expensive and complicated repairs due to below-grade leaks, always choose and properly install high-quality below-grade waterproofing and drainage solutions like Polyguard products.

Don't hesitate to contact a Polyguard professional for all your questions concerning new construction foundation waterproofing methods.

Related Posts

Explore our articles to learn more about products in application.

Types Of Soil Remediation Techniques For Restoring Contaminated Soil
Residential
Carrie Powers
Carrie Powers
June 1, 2025

Types Of Soil Remediation Techniques For Restoring Contamina...

Soil remediation methods provide contaminated soil solutions to restore soil to its natural, pollution-free state. Remediation of soil pollution purifies and revitalizes the soil by removing…

Can Termites Eat Concrete?
Residential
Carrie Powers
Carrie Powers
May 22, 2025

Can Termites Eat Concrete?

The term "concrete termites" conjures images of super-pests chewing through solid building materials. This common misconception leads many property owners to wonder: can termites actually eat…

What Is the Best Underlayment for Tile Floors?
Residential
Carrie Powers
Carrie Powers
May 8, 2025

What Is the Best Underlayment for Tile Floors?

Cracked tiles, moisture damage, and uneven floors are problems no one wants to face. Selecting the best installation layer for tile floors is essential if you want your tiles to last, looking…

Filling Gap Between Concrete Slab and Wall: Why It Matters and How to Do It Right
Residential
Carrie Powers
Carrie Powers
April 24, 2025

Filling Gap Between Concrete Slab and Wall: Why It Matters a...

Even small gaps—like the ones between concrete slabs and walls—can turn into big problems if they’re left alone. Moisture sneaks in, pests find their way through, and over time, you could be looking…

Metal Building Window Flashing: A Practical Guide to Getting It Right
Residential
Carrie Powers
Carrie Powers
April 3, 2025

Metal Building Window Flashing: A Practical Guide to Getting...

Water finds its way into metal buildings faster than many people expect. If a window isn’t flashed correctly, leaks around the frame can lead to corrosion, ruined insulation, and structural damage…

Does Crawl Space Encapsulation Add Value to Home & Other Benefits?
Residential
Carrie Powers
Carrie Powers
March 13, 2025

Does Crawl Space Encapsulation Add Value to Home & Other Ben...

Crawl space encapsulation is more than just a home improvement trend; it’s a strategic investment that offers long-term benefits. Homeowners looking to increase property value, reduce energy costs,…

How to Install A Vapor Barrier on a Concrete Floor
Residential
Carrie Powers
Carrie Powers
February 13, 2025

How to Install A Vapor Barrier on a Concrete Floor

Installing a vapor barrier on a concrete floor is a proven way to protect flooring materials and prevent moisture-related damage. Whether for residential, commercial, or industrial applications, the…

Innovative Ways to Prevent Ice Damming with High-Performance Roof Underlayments
Residential
Carrie Powers
Carrie Powers
February 6, 2025

Innovative Ways to Prevent Ice Damming with High-Performance...

Ice dams are a persistent issue for homeowners, causing water infiltration that leads to costly repairs and potential structural damage. Preventing ice dams is crucial to protecting your roof and…

Dealing With Contaminated Soil in Construction Projects
Residential
Carrie Powers
Carrie Powers
February 1, 2025

Dealing With Contaminated Soil in Construction Projects

tamination management requires safe, compliant, and expensive handling of the toxic-harmful materials, which can further delay your project's start time. To avoid potential harm to the environment,…

Understanding Termite Prevention Treatment Costs: A Comprehensive Guide for Homeowners
Residential
Carrie Powers
Carrie Powers
January 23, 2025

Understanding Termite Prevention Treatment Costs: A Comprehe...

Termites cause billions of dollars in structural damage annually, leaving homeowners with costly repairs. Knowing termite prevention treatment costs helps homeowners make informed decisions to…

Moisture Barrier for Basement Floor: A Foundation for a Dry Space
Residential
Carrie Powers
Carrie Powers
January 2, 2025

Moisture Barrier for Basement Floor: A Foundation for a Dry ...

Basement moisture issues often start with the ground below the concrete slab. Moisture and water vapor from the soil can travel upward, seeping through the slab into the basement.

Before and After Crawl Space Encapsulation: Transformations
Residential
Carrie Powers
Carrie Powers
December 12, 2024

Before and After Crawl Space Encapsulation: Transformations

Crawl space encapsulation is a highly effective way to address common household concerns, such as moisture buildup, pest infestations, and energy inefficiency.