What Is PU Grouting: How To Fill In Wall Cracks ?

Filling cracks with injection PU grouting is a useful procedure that helps provide waterproofing and corrosion protection for structural purposes.

A variety of grouts are available on the market with different characteristics, properties and uses. Generally, grouts used for crack repair should have low viscosity, high bond strength, low shrinkage and high stability at the repair temperature.

The main types of grout used for injection are cementitious grouts, epoxy resins, polyurethane resins and acrylic resins. A particular grout may be ideal for one purpose but inappropriate for another. It is therefore important to understand the characteristics of the different types of injection grout before selecting it.

Main types of injection grout

• Cementitious grouts are composed of a combination of cement and water, plus admixes or additives to alter their properties. There are three main types – pure cement mixes (PCMs) composed of cement and water, admixed cement mixes (ACMs) composed of PCM and admixtures, and additive cement mixes (ADCMs) composed of ACM and additives.
• Epoxy resins contain resin and hardener, which react to form a nonfoaming elastic grout that doesn’t bond as well to wet surfaces. They adhere well to metals, concrete and ceramics, show little volume change during and after curing, are mechanically strong and resistant to chemicals.
• Polyurethane resins can be used for a range of different applications. Their properties can vary markedly in terms of their liquid or hardened phases, viscosity, thixotropy, foaming reaction (in the case of hydrophilic resins), and mechanical strength. In general, they have a notably low viscosity, cure rapidly and are flexible. Polyurethane resins are also selected for their ability to seal against water inflows.
• Acrylic resins are formed from a polymerisation reaction between resin and hardener. The grout forms a permanent gel, which has low adhesive and compressive strength, but high tear strength. Different types of additive may be added to the mix to hasten or prolong the reaction.

Always refer to technical data sheets or talk with the experts

Every project location has different conditions and PU grouting requirements. We have developed a range of injection grout materials to meet the various needs, whether those involve structural repair or waterproofing.

Our product range includes high-quality epoxy and polyurethane resins that can assist in a wide variety of crack injection repair jobs.

For further information about how to correctly mix and inject our different grouts, please refer to the specific technical data sheets on our website or get in touch with us today.