The building stock
Southbank is Melbourne’s densest concentration of tall residential and mixed-use towers, most constructed from the 1990s onward. The defect profile differs entirely from that of the older inner suburbs: this is a facade-systems and building-envelope environment rather than a spalling-brickwork one.
Typical defect profile
Sealant is the recurring scope. Precast and curtain-wall towers rely on sealant joints for weather-tightness, and sealant has a design life measured in a decade or two rather than the life of the building. Once it fails, water enters at the joints, tracks internally, and produces a leak with no apparent source, generating repeat trade attendances that do not locate the entry point. A whole-of-facade sealant replacement programme is frequently the most effective single remedial expenditure on a tower of this era.
Podium decks and planters over occupied space. Almost every Southbank development has trafficable and landscaped areas above carparks, retail tenancies or apartments. These fail at details — upturns, drainage outlets and planter terminations — and the damage presents as staining in the space below, often a considerable distance from the breach.
Cladding compliance. Buildings approved between the late 1990s and 2018 are the most likely to carry combustible cladding. Rectification is a design and approvals exercise before it is a construction one, and it proceeds on the basis of fire-engineered assessment and building surveyor approval rather than contractor preference.
Precast panel fixings. Corrosion at panel fixings produces localised spalling at panel edges: low in volume, distributed across a tall elevation, and therefore an access problem more than a repair problem.
Access and cost
On a Southbank tower, the repair work is often a small fraction of the project cost and access accounts for the remainder. Scaffolding a 20-storey building to replace distributed sealant joints is rarely economic; rope access or a swing stage is generally the appropriate method, and the crossover point depends on the quantity of work per elevation.
Defect density is therefore mapped before an access method is selected. Buildings that invest in certified permanent anchor points reduce the cost of every subsequent facade inspection, sealant campaign and make-safe.
Works in occupied buildings
Buildings in Southbank remain occupied and trading throughout the works, and methodologies are built around that constraint: exclusion zones managed with building management, works staged elevation by elevation, out-of-hours arrangements where tenancies require them, and communication protocols so that residents and tenants are advised of the works in advance.