Navigating Negative-Side Waterproofing

Nov 29, 2023 | Construction Products, News

In the realm of construction, the intricacies of waterproofing demand careful consideration, especially when facing challenges related to space constraints or specific structural configurations. One such solution that comes to the forefront is Negative-Side Waterproofing. Let’s delve into what this method entails, its limitations, material options, advantages, and the crucial process of substrate preparation.

• Understanding Negative-Side Waterproofing

  What is Negative-Side Waterproofing?

  Negative-Side Waterproofing involves applying waterproofing materials to the interior side of a building’s foundation or wall, where accessing the exterior for traditional waterproofing may pose challenges.

  Challenges and Limitations:

  While effective in preventing water entry into occupied spaces, Negative-Side Waterproofing has limitations. It won’t stop water from entering the substrate. Unsuitable for environments with corrosive soil or specific interior humidity limitations.

• Material Options for Negative-Side Waterproofing

• 1 | Crystalline Coatings

  • Comprised of a one-component product with silica-based materials.
  • Ideal for projects such as water storage, treatment structures, basements, and retaining walls.
  • Forms insoluble calcium silicate crystals to waterproof concrete while allowing water vapour to pass.

• 2 | Flexible Cementitious Coatings

  • Highly flexible, fiber-reinforced, breathable cementitious slurries.
  • Suitable for positive and negative waterproofing, new construction, and restoration.
  • Used over minor cracks to provide bridging in applications like water and wastewater tanks, tunnels, and balconies.

• 3 | Advantages of Negative-Side Waterproofing

  1. Ease of Application
  • • Training is straight forward, and application is user-friendly.
  1. Cost-Effectiveness
  • • Offers a budget-friendly solution for effective waterproofing.
  1. Visibility and Repairability
     • Provides visibility during application, allowing for easy repairs if needed.
  2. Convenience
     • Can be applied any time after substrate material curing.

• 4 | Substrate Preparation for Success

  Regardless of the chosen material, proper substrate preparation is essential:

  Surface Cleaning: Remove coatings, paints, efflorescence, and foreign materials hindering penetration and bonding.

  Profile Enhancement: Consider sandblasting, mechanical abrading, shotblasting, or high-pressure water blasting for a better substrate profile.

  Dealing with Active Water Leaks: In situations with actively flowing water leaks, consider hydraulic cement:

  • Effectively plugs active leaks.
  • Sets within minutes.
  • Requires caution, including wearing a respirator and avoiding skin contact due to its highly alkaline cement base.

By Nadine Shürmann