- in Blog
Below ground tanking & retaining walls require best practice waterproofing techniques.
If the following principles are adhered to, there is no reason small retaining wall projects cannot be applied as DIY application.
- Quality Waterproofing Product.
- Good Preparation.
- Correct Waterproofing Application.
- Robust Membrane Protection.
Commercial & Large Waterproofing Projects
Below Ground Tanking , Basements & Under Concrete Slab
should be performed by professional waterproofing companies.
Consequences of below ground membrane failure is costly & difficult to rectify.
Registered Builders & Specialist Melbourne Waterproofers:
Choosing Retaining Wall Waterproofing Products
- Concrete block, masonry or bricks are porous in nature.
- Cracks and porosity of the wall materials allow water and moisture to penetrate from adjacent soil to interior walls.
ALWAYS use a WATERPROOFING PRODUCT and not DAMP PROOF.
- Although these two waterproofing products may look very similar, they are VERY DIFFERENT in how they perform.
- Many contractors continue to use dampproofing because once the foundation is backfilled the area is “out of sight, out of mind”, and once the house is finished and sold it becomes the homeowner’s problem if the foundation starts to leak.
- The small amount of money you save by not using proper waterproofing when the home is built, can cost you a lot of money to fix when water appears in your basement after one or two years, or even sooner.
What is Waterproofing?
Waterproofing products are designed to “prevent” water penetration even under wet conditions such as hydrostatic pressure in the soil after heavy rain storms or spring thaws.
Liquid Rubber Membranes
- Liquid waterproofing membranes have the advantages of quick application, cost effective, excellent flexibility for structural movement and elongation to bridge masonry wall cracks.
- Liquid Applied Waterproofing products contain rubber which provides superior waterproofing protection and allows the membrane to remain flexible even when it dries.
- This flexibility allows the waterproofing membrane to stretch as the foundation settles and bridge small hairline settlement cracks that can occur in the concrete or block.
- Liquid Rubber has robust adhesion to masonry and the membrane will not dry out, crack or peel off the wall.
- Retaining Wall waterproofing products selected MUST be able to withstand ponding water.
- Ponding or standing water, is water and/or moisture that pools on a surface.
- This is particularly important for below ground waterproofing as moisture tends to sit at the footings - the cove joint.
- There are a number of waterproofing products on the market that cannot withstand ponding water.
- These membranes will break down over time and water will leak through into the interior space.
Retaining Wall Waterproofing-Preparation
Prior to membrane application for retaining walls, it is critical to have good preparation & detailing between the vertical wall interfaces and foundation.
- It is critical this area is reinforced, using a Geotextile Bandage, which provides extra robust membrane adherence.
View Video below demonstrating how to apply the Geotextile Bandage.
Cement Block Waterproofing-Preparation
- Attention to preparation is required to treat voids, form-tie holes, and joints.
- At the wall-footing joint, you may be required to use cement or other trowel-grade material to form a "fillet" (radius or cove) before applying the overall coating.
- Inevitably small holes and cracks are missed with the sealant. It is very difficult to be 100%.
- This is where Liquid Applied Waterproofing will bridge divots etc, making these water tight.
Retaining wall bagged & prepped for waterproofing
DIY Waterproofing Application
- Liquid Rubber membranes form a seamless, one coat permanent water tight barrier.
- Applied directly to the retaining wall or foundation, Liquid Rubber forms a seamless, fully adhered rubberized membrane that will not let water in, and being an elastomeric coating will bridge cracks that often form as foundations settle.
- Waterproofing can be applied in just a few hours- surfaces area size dependent -using a trowel or brush.
- Liquid Rubber comes in 15L Pails and provides coverage approx 20 sq/m per bucket.
- Our recommendation is minimum 2 coats - touch dry between the coats.
Retaining Wall Membrane Protection
Below ground leaks are expensive to rectify and also an extremely challenging job to remedy on the negative side.
- A very common problem is the failure to provide adequate protection for a newly installed and perfectly good membrane.
ARMA-BLUE Protection Sheet - robust & permanent.
- A common cause of retaining wall membrane damaged due to allowing sharp material (such as gravel) during backfill.
- Stones have the potential to puncture a waterproofing membrane.
- However with a bit of due diligence and care, this can be prevented by using a robust & permanent protection sheet.
We use ARMA-BLUE.
This is a composite medium with cross linked foam to provide strength & durability.
Huge benefits over conventional & cheaper Corflute.
- Will not decay or rot below ground.
- High abrasion resistance.
- Also acts as an extra water barrier.
- Great for DIY - Easy to cut.
- Great for DIY - Fast installation.
- Great for DIY - Easy to handle & Lightweight.