Best waterproofing tips for balconies – from the experts

Modern beautiful luxury hotel resort building

Every strata manager and apartment owner will understand the importance of a well-maintained balcony… and waterproofers agree. Balconies are one of the most common areas for waterproofing failures, so high-quality waterproofing and attention to maintenance is crucial.

Danrae Group are waterproofing experts, so we know the ins and outs of waterproofing for balconies. Effective waterproofing needs efficient diagnostic, design, and remediation – and that starts with identifying your problem.

Here’s a quick Danrae Group guide to common balcony waterproofing problems, how to recognise them, and what to do next.

Rain drops crashing on balcony rail

Leaking balcony basics

Waterproofing faults in balconies may stem from the initial design and lack of planning prior to construction, or from inadequate property maintenance. Effective solution design should prevent water ingress into a building by allowing for inadequate flow away from the roof or façade. It will incorporate appropriately sized drains, the correct number of drain outlets, and materials suitable both for balcony and environment.

Effective waterproofing also requires a holistic approach. A quality membrane installed on a balcony is of little use if the layers above it have problems.

Tiles for instance may provide a channel for water to enter and damage the membrane if they are the wrong material for the location (too porous), or if they have shifted due to an adequate number of expansion joints.

It’s standard for environmental factors such as storms, winds, or rain to impact your waterproofing, but quality design and materials, together with regular preventative maintenance, will ensure that impact is minimised.

Concrete cancer and concrete spalling

What the signs are and when to act

For strata managers, the most obvious waterproofing issue is likely to be a leak into apartments, and it may impact one or several tenants. Not all waterproofing faults are quite so obvious, however.

Water ingress within walls may occur slowly and not be immediately visible. During this time, it may affect the building structure and the first signs of damage may take several forms including mould, flaking paint, cracks, or crumbling walls.

That damage may lead to common issues such as efflorescence, concrete spalling, or concrete cancer. And it will always worsen if left untreated.

For property managers, the benefits of early detection and treatment – and preventative maintenance – are clear. It will protect the health and safety of your tenants, it will save you a larger repair bill, and it will help maintain the integrity – and value – of your property.

Point Piper Project

A typical remedy

One of our projects involved the repair of a balcony and gutter in Point Piper. The owner had issues with leaks from a large balcony and adjacent gutter.

Sheet membranes are advisable for balconies. Some varieties such as WPM 1000 by Ardex or the SCHÖNOX system by Sika allow tiles to be overlaid directly. Generally, you will need an underlying screed with a salt retardant and moisture barrier. For the Point Piper project we removed the existing sheet membrane, installed a new Sika Sarnafil PVC membrane to both balcony and gutter, and as part of our end-to-end project management ensured the complete area was watertight and finished to exceptional quality prior to final testing.

With a large in-house team of remediation experts including tilers, builders and carpenters, we can make sure every balcony is in pristine condition at the end of every job.

Closeup view of the exterior of the modern building

Projects finished to perfection

At Danrae Group, we incorporate proven processes into every project. We look after every detail including council permits, tenant communications and remedial building, and we plan ahead with preventative maintenance.

We believe that strata managers and property owners should place high precedence on prevention to preserve the quality of a sound waterproofing solution – and ensure your warranty is maintained.

If you have signs of water damage in balconies, basements, planter boxes, your building facade or roof, then now is the time to get in touch. Read more about waterproofing techniques.

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