Below Ground Tanking

Liquid Applied Waterproofing Membranes -
Basement, Foundations & Retaining Walls

Waterproofing Method for Basements

Unlike other building components that might be designed to be replaced several times within the overall building lifetime, below grade systems need to be built to approximate the entire service life of a building.

View Video Below - Basement Waterproofing - Case Study

Findlay-Evans Waterproofing applying Liquid Rubber waterproofing membrane on a below ground retaining wall.

  • Below ground waterproofing is as important as the very structural foundations supporting a building.
  • Without the combination of watertight footings & foundations, a building will deteriorate rapidly.
  • Very often, below grade waterproofing systems are inaccessible for repairs.
  • In some projects, it may not be even commercially viable, or even possible, to fix failed basement membranes.
  • Negative waterproofing methods, crack injection systems, can be used to attempt to rectified leaking basements from the inside.   

Below Ground Tanking

Below Ground & Basements

Repairs to leaking basements can be extremely costly if rectifications are necessary at a future date.

Below Ground Tanking - Getting It Right

  • Below ground tanking, retaining walls, foundations and basements require best practice waterproofing techniques - the consequences of membrane failure are huge.
  • Below ground waterproofing - it is imperative to get it right the first time.

View Case Study Video - Best Practice for Below Grade Tanking



"I have been in the construction industry for over 25 years, many of these as a Registered Building Practitioner specializing in waterproof coatings.

And it wasn't that long ago, nor was it unusual, for builders to instruct their labourers to quickly slap on anything black in colour as a waterproofing membrane!"

Paul Evans; Managing Director of Findlay-Evans Waterproofing & Liquid Rubber Melbourne
President of AIW (Australian Institute of Waterproofing)

Basement Tanking & Waterproofing

  • Spray On Waterproofing allows access to difficult below ground level areas, where sheet & torch-on systems it is not possible.
  • Liquid Rubber membranes have an unique elastic property that helps fill concrete cracks while still flexibility for structural movement.
  • Cold spray-applied systems are fast - very fast.
  • Liquid Membranes can conform to any shape required.
  • Excellent membrane to waterproof shotcrete application. 

Download FREE Below Ground Waterproofing Guide HERE

View Case Study Video - Using Spray On Liquid Waterproofing Membranes

Liquid Waterproofing Membranes for Under Concrete Slabs

Probably the worst thing that can happen to  basements and foundations - is WATER LEAKS.

  • Liquid Rubber systems are suitable to successfully seal vapours from reclaimed construction sites: reclaimed petrol station sites, chemical factory sites and seal off basements against radon gas. 
  • Liquid Rubber membranes are sprayed in a continuous seamless barrier, providing waterproofing protection horizontally, vertically up walls and upturns, and around pipes, penetrations. 
  • Stopping water from infiltrating below the subfloor requires choosing the correct waterproofing system together with experienced waterproofers.  
  • Also - don't overlook proper drainage! 

View Case Study Video - Using Spray Applied Liquid Membranes for Under Slab Waterproofing

Waterproofing Retaining Walls

  • Concrete is not waterproof - even with additives! These can take years to achieve the desired outcome and if the concrete moves & cracks the success of relying on concrete additives alone is questionable. 
  • Block work & masonry walls are porous.
  • At the time of construction - positive below ground tanking (exterior wall) should be applied to the foundation an/or retaining walls.
  • Climatic conditions will affect the foundation - wet soil beneath a basement/foundation can swell causing lose of strength. 

Unable to withstand "ponding" water

We have found over the years that many of the traditional waterproofing membranes often used for below ground tanking break down due to:

  • Sheet membranes with seams & joins can develop cracks and open up - very difficult to fix.
  • Cannot withstand "ponding" water - especially important at wall & slab junction. 
  • Leaks flexibility & membrane cannot move with normal structural expansion & contraction. 

Sheet membrane - seams & joins de-laminate

For years, our Team at Findlay-Evans have been looking for an alternative to the traditional bitumen/sheet/torch-on roofing waterproofing methods.

View Case Study Video - Protecting Your Membrane

  • Liquid Applied Membranes are the ideal below ground waterproofing system.  
  • These are membranes that form a seamless & impermeable waterproof coating on the exterior surface.  

How to Waterproof Basements

Findlay-Evans Waterproofing developed systematized waterproofing best practice for below ground tanking.

  • Liquid coatings have the advantages of quick application, low in-place cost combined with excellent elongation and elasticity.
  • Several layers of spray-on monolithic membranes are built up to the required thickness as specified.
  • The membrane extends down below the slab junction preventing water and water vapour from moving through the wall/structures.
  • Using the latest technology in spray-applied liquid waterproofing membranes means your project takes less than one-third the time than using traditional rolled membrane. 
  • No waiting for concrete to cure.
  • No priming required and back filling can commence as soon as the product is dry.
  • Liquid Membranes are hard wearing, seamless, monolithic and flexible systems that can also be structurally reinforced.

Find out more about Liquid Rubber Membranes:

Long Lasting Waterproofing is Worth Using

Quality Products & Experienced Applicators

Waterproofing represents around 1% of building costs water leaks and subsequent damage represent approx 80% of building defects. 

Below Ground Tanking Method

  1. 1
    Waterproofing Planning
  2. 2
    Waterproofing Preparation
  3. 3
    Waterproofing Membrane Installation
  4. 4
    Waterproofing Protection - Arma Blue

1. Waterproofing Planning

  • All our jobs are tracked on-site in real-time, project photos are logged & managed by a cloud based QA system while also providing instant SMS communication with our clients.
  • We are Registered Building Practitioners AND Certified Waterproofers.
  • FINDLAY-EVANS provide 25 year guarantee with expert professional service.
  • FINDLAY-EVANS provide a fully comprehensive on-line proposal offering multiple client options, testimonials & relevant past projects.

Lift Pit Waterproofing

2. Waterproo0fing Preparation

  • We don't skimp on below ground surface preparation - our aim is to get foundation walls and footings clean, free of loose material and smooth.
  • It is imperative below ground surfaces are dry and free of anything that could adversely affect MEMBRANE adhesion.

Waterproofing Concrete

3. Waterproofing Membrane Installation

  • When deciding what walls get waterproofed for below ground tanking, we follow this basic rule: waterproof any foundation wall that has earth on one side and usable space on the other - including sub-floor spaces.
  • We extend the membrane at least 300 mm onto intersecting walls even if they don't need to be waterproofed.
  • Information for DIY waterproofing concrete slab - see here

Retaining Wall Waterproofing

4. Waterproofing Protection - Arma Blue

  • Below ground waterproofing systems need protection during backfilling.
  • After several failed membrane due to inadequate protection we have our own self-adhesive protection sheet - ARMA BLUE.

Arma-Blue provides robust protection and being self-adhesive will not move, dislodge or allow stones etc to come between the protection sheet & membrane.
Read more about Arma-Blue here.

A waterproofing company that thinks CONSTRUCTION.

Use Liquid Applied Membranes for below ground, basement & foundation waterproofing new, existing, remedial and repair projects.

Read Client Testimonials here

  • Satisfies all OHS safety issues.
  • Are eco-friendly products and completely free of VOC’s
  • Does not involve heat/ fumes or torches.
  • Stable, non-toxic, odorless, non-flammable components which do not present a storage or transport hazard prior to, during or following application.

Findlay-Evans Waterproofing - Melbourne Waterproofing Contractors  & Registered Building Practitioner

Basement Case Studies - Download PDFs Here

Discover Our Latest News 

Melbourne’s Guide to Waterproofing Leaking Commercial Balconies
Trusted and Efficient Balcony Repairs in Melbourne
How to Get Your Leaky Balcony Fixed in Melbourne