Leaking Balcony Repairs - Specialist Waterproofers & Builders (Melbourne)

Balcony Repairs – Builders Melbourne

Balcony Repairs Builder Melbourne

Leaking Balconies & Structural Repairs 

Balconies and rooftop terraces are often created above living areas such as apartments, offices, retail & general living areas. Water ingress into occupied spaces can lead to not only interior damage but also structural damage to the building envelope.
Water ingress from balcony above

Water ingress from balcony above

Water ingress from balcony above

Water ingress from balcony above

Balcony Design & Australian Standards

  • The current design trend is for residential & commercial balconies to be constructed with minimal falls; this particularly evidenced in multi-level apartments.
  • Balcony design has a significant effect on the waterproofing method used and selecting the correct waterproofing product is critical.

Balcony Articles - Australian Standards & Technical Drawings

 Article : Balcony Waterproofing Membranes - Why do they Fail

 Master Builders Association (MBAV) - Balcony Technical Drawings

 Australian Institute of Waterproofing (AIW) AS4654.2

Waterproofing membranes for external above-ground use. Design and installation.

        What is "ponding" water?

  • It is the unwanted pooling of water on a flat roof or balcony.
  • Ponding water accelerates the deterioration of many materials.
  • This includes deterioration of membranes with seams & adhesives used on overlaps & joins and also steel equipment supports etc.
  • With minimal fall and low-slope balconies and roofs with old bituman/asphalt surfaces, ponding water allows the oil solvent components of the asphalt to leach out and evaporate.
  • This leaves the waterproof membrane brittle and susceptible to cracking and leaking in the ponding location. 

Ponding Water


Ponding Water

There are several critical issues unique to keeping a balcony water tight that are not always taken into consideration when designing balcony waterproofing systems. 

Recent article below highlights issues involved within commercial construction and leaking balconies.

"Melbourne’s high-rise nightmares taking a tall toll on residents and investors" 

Summary of the Article key points:

Residential multi-story, multi-dwelling, apartment buildings are experiencing an alarming frequency of building defects, most commonly caused through waterproofing failure.

Developers were identified as partly responsible for the condition of the building, with a call to be financially responsible.

Balconies were identified as a major cause of waterproofing problems, with the assumption that“proper waterproofing membranes have not been installed”.

Faulty windows and installation process causes considerable water leaks into walls and ceilings.Pressure issues identified as causes were nominated as; a failure to pick up defects through the building surveyors inspection process; plus the cost pressures to use cheap (inferior) materials to save money.

The market has inconsistencies in Insurance cover, both from building trade cover and the residential owners cover. Resulting in the building owner necessitating to self -fund the corrections to the building.

The Victorian Government is making new laws to protect consumers whilst also recognising the‘overwhelming majority of builders’ do the right thing.

 Article from The Age Melbourne 25th September 2016: http://www.theage.com.au/victoria/-gri6l4.html

       Why Balconies Leak

  • Images below -  due to the membrane lacking flexibility and drying out over time with cracks appearing.
  • The waterproof system may not have the necessary thermal expansion & contraction capabilities.
  • Balcony membranes need to move with normal thermal cycle of the balcony materials and adjacent building envelope.
  • Poor waterproofing membrane transition between different surfaces, penetrations and interfaces - i.e vertical walls, balustrades etc - leaving areas of weakness for potential water ingress.
  • Membranes must adhere, create a bond and seal around all surfaces and still maintain long term flexibility.
  • Don't underestimate the power of wind driven rain to penetrate the building envelope if flashings etc are not water tight.
Membrane dried & cracked

Membrane dried & cracked

Sheet membrane overlap

Even small amounts of pooling water will cause moisture to seep down through the grout lines and sit between the membrane and tile.

Many waterproofing products used on balconies deteriorate over time with moisture continuously sitting between the tile and membrane.

Moisture seeps through tile grout

Moisture seeps through tile grout

Moisture seeps through tile grout

Moisture seeps through tile grout

Moisture seeps through tile grout

Balcony Waterproofing Products

Best Waterproofing System for Balconies

Tiling by the way, is not an effective or acceptable waterproofing product on its own.

  • The correct approach, obviously,  is the installation of an appropriate and robust waterproofing membrane system that "works and lasts".
  • A basic principle of construction is movement of the building envelope will occur.
  • Therefore a waterproof membrane must be able flexible to accommodate structural movement.
  • Balcony systems must permanently seal all wall/floor joints, drains, balustrade, water exit points, hobs, sheet joints and movement joints.
  • Penetration of water through the balcony surfaces and/or the exposed balcony edges of both reinforced concrete and timber framed balconies can lead to structural deterioration.
  • For concrete structures this leads to significant construction defects, such as concrete spalling.
  • Selecting quality waterproofing products, using meticulous balcony preparation and implementing correct membrane application methods are all critical components of successful balcony repairs

Joins "detailed"prior to waterproofing

Detailing balcony balustrade

Balcony preparation requires meticulous detailing prior to applying the waterproof membrane.

Waterproofing Products to Fix Leaking Balconies

  • We recommend Liquid Applied Membranes for the Australian climate as the most practical and economical waterproofing product for balcony repair projects.
  • Liquid waterproof systems are seamless and spray applied - no joins, overlaps or seams to come apart.
  • These systems can be used on the most complex of details, which are often found, for instance, around handrail supports, thresholds, rainwater outlets and downspouts.
  •  Seamless liquid applied elastomeric have become the ultimate repair solution for balcony and deck waterproofing.
spray applied liquid waterproofing membrane

Spray applied liquid waterproofing membrane

Registered Builder Waterproofing Specialists Melbourne

Benefits of Using Liquid Applied Membranes

Liquid Rubber is a spray-applied liquid waterproofing membrane that provides a seamless environmentally safe and highly flexible membrane that will "hold" and "contain" water without breaking down.  

    Liquid Applied Membranes

  • High Performance & Robust Adherence.
  • Cost effective & long life waterproofing.
  • Fast spray application with minimal disruption to building occupants.
  • Liquid waterproof systems contour to the structural shape. 
  • Extreme flexibility so will move structural expansion & contraction. 
  • Suitable for concrete, timber and metal surfaces. 

Liquid Applied Membrane - seamless & flexible

commercial balcony waterproofing Melbourne

Balcony Liquid Membranes

Repairs to Leaking Balconies

  • Choose a membrane suitable for balcony structural movement.
  • Complete ALL penetrating works PRIOR to applying waterproofing membrane.
  • Ensure penetrating structures have additional sealant around them.
  • Ensure balcony levels have good drainage system so water does not pool.
  •  Best to remove A/C unit while prior to waterproofing repairs  - much tidier job. 
  • Water test the membrane BEFORE tiling–ensure the membrane is water tight.. 

How to Fix Leaking Balcony  

Waterproof a Balcony Without Removing Tiles

  • Re-Grouting and sealing is defiantly not the way to repair a leaking balcony that has a defective membrane.
  • This would probably slow or stop down leaks for a while - that is until the sealant/grout moves and cracks start to leak again.
  • Laying a new waterproof membrane over clean existing surfaces can work  ONLY if the existing tiles are soundly fixed.
  • Very often there may be some blistering of the new membrane due to water vapour trapped within the existing tiles.
  • This is easily managed as it basically just takes time for the vapour to dissipate - with the new membrane over the top of existing tiles.
  • Warning - Great attention needs to be given to the waterproofing products used.

Balcony Articles - Australian Standards & Technical Drawings

 Article : Balcony Waterproofing Membranes - Why do they Fail

 Master Builders Association (MBAV) - Balcony Technical Drawings

 Australian Institute of Waterproofing (AIW) AS4654.2

Waterproofing membranes for external above-ground use. Design and installation.

Registered Builder Waterproofing Specialists Melbourne

Building Services Australia

Providing Specialist Remedial Construction & Waterproofing Services in Melbourne.