Polyurethane (Leaking) Crack Injection

Polyurethane crack injection is without a doubt the most effective leaking crack repair method in concrete. The widespread use of polyurethane, sometimes referred to as urethane or grout, for concrete crack injection is a tribute to the inherent versatility of low viscosity polyurethane injection resins for leak sealing applications. Polyurethane crack injection is commonly used in civil, commercial and residential applications.

Properties of polyurethane

Polyurethane is a fluid resin which is injected into concrete cracks, rock fissures, expansion joints and other voids in concrete structures.When used in concrete crack injection applications the polyurethane is injected into a crack.within minutes the polyurethane undergoes a chemical transformation from a liquid to a solid.

The versatility, and consequently the popularity, of polyurethane resins in crack injection applications stems from polyurethane’s properties:

It has a very short cure time, making it ideal for active leak sealing.

Extremely low viscosity allowing for even the finest fishers (cracks with a width less than 0.2mm) to be sealed.

The resin cures normally whether a foundation crack is wet, actively leaking, or damp.

There are literally thousands of polyurethane resin formulations which is useful when repairing foundation cracks because the viscosity of the resin and cure time can be controlled.

Polyurethane, once cured, can be quite flexible, allowing for movement in the structure and leak leaks to remain sealed.

Any leak in a concrete structure can be sealed.

Polyurethane crack injection is used in civil construction and maintenance of civil assets due to its flexibility in application and its reliability in repairing cracks and damage in concrete structures. Polyurethane crack injection is the most efficient and cost effective method in repairing leaking cracks in major concrete assets.


Civil water – treatment plants, town water supply, pump stations, channels, canals

Sewage treatment plants – high voltage electrical pits, man holes, chemical storage areas

Dams – diversion tunnels, dam walls, permanent plugs, dam walls.

Tunnels – rail, road, access and electrical

Underground structures