Reducing risk on vintage rooftop with collapsing balustrade

CHALLENGES

Some vintage buildings feature a flat rooftop area which can be tempting for building occupants to access, rightfully or illicitly, for outdoor enjoyment. However, unless the building was originally designed to have a usable rooftop terrace, the rooftop area may not be structurally sufficient to support usage. Combined with any deficits in modern-day safety requirements, such as compliant balustrading, the inappropriate use of rooftop areas by anyone can put them, other people, and the property at risk. Sometimes building owners make the decision to invest in getting structural work done to convert the rooftop into a usable outdoor area where this is permissible. Notwithstanding any lack of enhancement, the flat rooftop area still needs to be maintained for the ongoing safety of workers, preservation of structural integrity, and protection from rainwater ingress.

Strata Engineering Solutions (SES) engineers were called to report on the flat rooftop of a vintage multi-storey building in Coogee Bay Road, Coogee, where a masonry pillar supporting a section of the rooftop balustrading had partially collapsed. The original balustrading was not compliant by contemporary standards, the existing steel rails were visibly corroded, and most of the original wire-mesh infill panels were missing.

For effective remediation works to be completed, the existing structural elements on the rooftop would need to be dismantled to make way for new balustrades. The building was never designed for routine use of the rooftop area, only for occasional access by maintenance workers, but still, the balustrades would need to be compliant. The new, compliant balustrades would be installed to the building’s existing aged timber roof structure. The waterproofing integrity of the rooftop would need to be maintained during and following the works.

SOLUTIONS

The original timber roof was locally reinforced along the perimeter to accommodate the new balustrades. Waterproofing around the perimeter was reinstated to retain a watertight rooftop.

RESULTS

The new balustrades are compliant and the rooftop area is now safely accessible for use by building maintenance personnel. There is no risk of deteriorated materials falling onto the street below. The aesthetics of the building have been updated.

• Collapses
• Compliance Issues
• Concrete Defects
• Structural & Aesthetic Issues