Concrete spalling and waterside strata apartments

Stunning View of the Ocean Beach and Luxury Resorts With Swimming Pools Surrounded by Palm Trees

We all know that in real estate, location matters. For waterproofing, it certainly does, too. In a waterproofing fix for a Rose Bay apartment last year, Danrae Group discovered extensive concrete spalling beneath what looked to be minor damage in a ceiling.

It’s not uncommon for concrete spalling to spread undetected, and for waterside apartments such as this one, the location can potentially increase the risks of issues such as efflorescence, concrete spalling and concrete cancer.

Here’s the Danrae Group guide to concrete spalling and waterside strata properties, including areas most prone to spalling, and our recommended waterproofing treatments.

Rusty rebar with old concrete bridge

Causes of concrete spalling

Concrete structures are built around an internal steel framework. Any exposure to air or water creates a carbonic acid that can cause the steel to corrode. With corrosion, the steel expands or begins to degrade, providing more space for water to enter the internal structure, cracking the concrete and accelerating the condition.

Concrete spalling is the initial stage of this process, with common signs including cracking, crumbling or flaking concrete, rust stains, bubbling paint and leaks. When concrete spalling continues unchecked, it leads directly to concrete cancer.

There are several potential triggers for concrete spalling related to workmanship, including poor quality waterproofing, inadequate preparation of the reinforcing steel during construction, incompatible support metals or stress fractures from excessive weight.

Harsh climates and storms may also lead to concrete spalling and cancer, and for those near the ocean, there’s a very common factor – saltwater corrosion, spread by ocean spray.

home with ocean views blue sky and contemporary construction

Strata areas at risk

Ocean spray spreads salt, which your concrete can absorb in tiny increments, and it has a cumulative effect, so that over time layers of salt begin to cause erosion and damage, often in tandem with other climate factors such as extreme heat, wild weather and strong winds.

Commonly, saltwater corrosion occurs in areas exposed to the elements – and where you’re likely to be enjoying your water views – such as flat roofs and balconies.

Additionally, we often find spalling or concrete cancer in planter boxes, on building facades and around windows and doors.

Man on a rooftop doing a waterproof treatment

Our concrete spalling treatments...

At Danrae Group, we have an extensive in-house team of waterproofing specialists with full capability in concrete spalling detection and treatment for strata, civil, commercial and government projects.

After thorough diagnosis and testing, we provide you with a solution design tailored to your property and taking into account location and usage – such as high foot traffic rooftop gardens.

Generally, our process involves site preparation, removal of the damaged concrete, treatment or replacement of the affected steel and concrete, and the application of an anti-carbonation coating or another specialist coating to strengthen and preserve the concrete. For waterfront properties, we might opt for a site-specific electrochemical treatment.

After installation of your waterproofing membrane, we provide full remediation, including deck or balcony reconstruction, and site clean-up. As part of our complete project management, we liaise with all stakeholders, including strata tenants.

Man at the rooftop holding a paint roller

...and preventative maintenance recommendations

At Danrae Group, we regularly see the effects of concrete spalling and concrete cancer. If left unchecked, these issues always worsen, leading to more extensive and more costly remediation.

Given properties near the ocean are particularly prone to concrete spalling and concrete cancer, ongoing preventative maintenance is important to rectify any potential issues early.

Danrae Group has provided first-class waterproofing for decades, and we guarantee our quality. Read more about our waterproofing maintenance, or to discuss your project, please contact us.

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