construction site

What Kind Of Water Stop Do I Need?

A water stop is used to create a watertight seal in concrete construction. Almost every concrete structure includes seams and joints where different areas of the concrete meet and a water stop is designed to ensure that joints cannot be penetrated by water. A water stop for concrete walls is often used in building, swimming pools, showers, baths and other areas where water or moisture may be found. Waterproofing supplies have many different uses in both residential buildings and also have commercial applications.

What kinds of water stop exist?

A water stop is usually installed in the joints of concrete to create a seal. There are different types to suit different constructions.

PVC designs

Firstly, there is PVC water stop designs which are usually included into the concrete pour. This ensure that the water stop is properly secured and stop liquid from entering the joint. It is possible to weld them together to create a waterproof barrier. They are available in different profiles which are called rear guard and centre stop. Centre stop designs are usually fitted between two concrete slabs whilst rear guard are placed at the back of the concrete slab. They are usually placed against the form work of the design. A PVC water stop comes in many different sizes and can work with both expansion and construction joints. Versions used for expansion joints include a hollow tube in the middle to allow for the joint to expand or contract. Construction joint designs include a flatter profile and down have the hollow tube.


Hydrotite designs are made from rubber that expands when it comes into contact with a joint. They are usually secured into the joint when the concrete is first poured. They swell on contact with water and fill up the space to create a barrier. In certain situations, a mixture of designs may be joined together to make the right seal. 

Polyurethane water sealants

It’s also possible to waterproof with polyurethane sealants like Leakmaster which is useful on rough surfaces and is good for joins where a normal solid sealant can not be easily applied. It’s very useful for when there isn’t a good seal and Hydrotite and PVC can’t be applied.

Chemically resistant water stop

Chemically resistant designs do not swell similar to PVC but are made out of rubber and designed to be resistant to chemicals.

What size do I need?

The size you need depends on the height and width of the concrete slab. For example, a 200mm thick concrete slab requires a 200mm water stop.

Hydrophilic designs and PVC are great for creating a seal and preventing water from escaping. The way they are installed depends on the type you choose. Rubber designs are great for filling cracks and voids. They are affordable and regularly used in many different industries to prevent water from leaking into structures.

If you’re wondering about the right waterproofing solution for your needs, then it’s a good idea to speak to an expert consultant as they will be able to advise you what you need based on the concrete slabs that you’re working with and what the project is that you’re working on.

Waterproofing is an important and necessary steps for many different constructions. Without it water can cause damage to structure and mould or structural issues can develop, weakening structures and creating potentially dangerous issues which can be costly to repair. Prevent your structures from warping or becoming damaged by investing in the right water stop solution for your project. Look online or ask a professional to find the right solution.