Waterproofing Leaks

Waterproofing of Below Ground Structures?

At Grace, we specialise in providing top-notch waterproofing solutions for below-ground concrete structures in New Zealand. Our approach involves working from the inside out, minimising the need for extensive excavation of external walls.

During the construction phase, below-ground structures face the risk of exposure to water and mud, potentially jeopardising the integrity of the existing waterproofing membrane.

Over time, concrete slabs and walls may develop small cracks due to various factors, such as shrinkage, poor workmanship, or constant wetting and drying. While these cracks may not initially affect the structural stability of the concrete, they can compromise the effectiveness of waterproofing, leading to water leaks.

Such leaks can cause concrete deterioration and spalling, ultimately compromising the structural capacity of the concrete elements.

To address these challenges, we utilise a specialised polyurethane injection resin that reacts with water and moisture. This innovative approach ensures waterproofing even on the negative side of the wall, providing a long-term and effective solution.

Our solutions are not only preventive but also suitable for remedial work. In cases where cracks or leaks occur in water-retaining structures and treatment plants, our crack leak sealing technique proves highly effective.

Remedial work for crack leak sealing

Our leak sealing resin injection method involves using foaming polyurethane resins, injected with specialised pumps. This approach works for both high and low-water flow leaks. The process includes drilling holes into the affected area, inserting packers, and injecting the leak-sealing resin through the packers. Notably, Grace is a certified specialist installer of Alchatek resin injection products.

One of the key advantages of our preferred solution is its ability to maintain a watertight seal while accommodating variable and high levels of movement in one or more directions.

This versatility allows us to effectively seal all types of joints and cracks in various structures and applications, including:

  • Tunnels and culverts
  • Hydroelectric power plants
  • Sewage treatment plants
  • Basements
  • Water retaining structures
  • Drinking water reservoirs

Our expertise extends to the sealing of:

  • Movement joints
  • Construction joints
  • Pipe penetrations
  • Cracks
  • Building components where differential settlement is expected

For your project’s individual needs, feel free to consult with us today, and our team will be delighted to provide you with the best-fit solution for superior waterproofing performance.

How we perform retaining wall inspections.


One of our knowledgeable inspectors will draw a scaled diagram of the home and take floor elevation measurements after thoroughly inspecting the property inside and out.


We only move to step two if an issue with the foundation is found during the inspection. Our inspector will design a repair plan specific to the property and the issues facing it. They’ll then provide you with a scaled CAD drawing of your home, a full report on the findings, and a suggested repair plan based on those findings will be provided.


We will engage any other professionals that maybe required, such as Geotech and or council and complete to plan.

Are you ready to learn more about what’s happening with your property’s foundations?