What Is a Waterstop?

A waterstop is designed to prevent water and other fluids, such as chemicals, from penetrating construction and expansion joints. It plays a significant role in strengthening a concrete structure.

Concrete is Australia’s most widely used building material, with around 10 million m³ of pre-mixed concrete poured in NSW each year. As the saying goes, “a chain is only as strong as its weakest link” and in concrete structures, a joint is the weakest part.

Waterstops are embedded in or run along joints where poured areas meet to create a watertight seal in concrete construction. They keep water in or out and are a vital component in the waterproofing design of any construction project, be it a home, parking basement, tunnel or dam. Without them, water and moisture can travel along construction joints to areas without waterproofing, causing damage.

Let’s look at where and why this waterproofing barrier is used to understand how this good design practice should be applied in construction projects.

The Different Types of Waterstops

Waterstops are made from varied materials, depending on their purpose and the type of joint. Construction cold joints occur where there are individual concrete placements with little movement.

Expansion joints separate adjacent concrete pours to allow for movement (between walls and floors, for example). In contrast, contraction or control joints are intentional grooves that control the location of cracks.

The two main product categories are PVC waterstops and swellable waterstops.

PVC waterstops

PVC waterstops are used in movement and construction joints. They have a bulb profile that creates a physical barrier when embedded in both sides of the joint. They are available in many sizes, last a long time and can be installed in all types of conditions. However, they need to be carefully positioned and secured so they do not shift during concrete placement to guarantee the integrity of waterproofing.

Swellable waterstops

Swellable waterstops are used in non-movement joints. A hydrophilic waterproofing sealant is placed on one face of the concrete joint before a second pour. The strip swells to seal concrete joint gaps as it is exposed to water.

They are typically manufactured from bentonite clay and rubber compounds, and installation is often easier than with PVC waterstops. They prevent water leakage by absorbing moisture from the surrounding environment and can expand by up to 300%.

At Illawarra Industrial Supplies, we stock both flexible PVC waterstops designed for longevity and swellable waterstops to generate a strong pressure seal.

Applications of Waterstops

Waterstops are used to prevent water infiltration in concrete construction joints for a variety of projects, including:

• Tunnels and bridges
• Dams and canals
• Water treatment facilities
• Parking garages and basements
• Between a wall and floor in commercial settings
• Decks in residential buildings and commercial applications

What are The Benefits of Using Waterstops?

Waterstops are a critical part of a building’s waterproofing system. This flexible waterproofing for concrete joints overcomes the material’s imperfections and helps strengthen structures, prevent leakage, and keep buildings watertight, preventing serious damage.

Rain and hydrostatic pressure can cause water to seep into the smallest crack in concrete, compromising the integrity of the entire structure. However, waterstops prevent moisture and water infiltration, presenting a cost-effective way to protect foundations, concrete slabs or structures long-term.

Why Buy Waterstops from Illawarra Industrial Supplies?

Waterproofing systems are only as strong as the materials used in them. High-quality products used for appropriate joint conditions ensure a waterproofing system will last.

From Sika to Amcol, Illawarra Industrial Supplies offers only the very best waterproofing products on the market to meet the requirements of our customers and give you peace of mind about the quality of materials you are using in your concrete construction projects.

Our services include working with clients on product selection and specification drafting. We understand that designing water management systems is a complicated process with a wide range of products on the market. We can offer this service because our team is highly knowledgeable and has the experience necessary to assist you with waterproofing solutions for any application.

Complete Your Waterproofing System with a Waterstop

An essential part of a waterproofing system, waterstops prevent small problems from becoming big ones that risk the structural integrity of construction. These flexible strip seals and barriers save time and money, but only if they are made of the highest-quality materials and applied correctly.

Illawarra Industrial Supplies offers durable waterproofing products and consulting services to ensure your construction project meets the highest standards. Contact us today at (02) 4271 3888 for the best advice on any coating, anti-corrosion, construction, or water management job, big or small, or visit our website for more information on any of our products.