Remedy Asset Protection (RemedyAP) was engaged by the owner of a commercial office building to identify and provide solutions for several corrosion issues affecting the structure.

Located in a coastal environment, this five-star rated 7000m² building was built to meet and exceed sustainability milestones, contributing to emissions reductions, water savings and business efficiencies including an innovative roof water harvesting project. The owner sought to maintain the premium aesthetic and functionality of the building. However, like most forms of construction, there were obvious defects remaining after completion, which almost 10 years later, had begun to present problems.

RemedyAP was engaged to provide their CorrAssure retroactive process for identifying the corrosion issues on the exterior surfaces.

The corrosivity type was identified as ‘C3 Environment Corrosivity Zone with Dissimilar Metal Coupling’.

Challenges:

Dissimilar metals

Construction often sees connection of dissimilar metals but it isn't always detrimental depending on the materials and fixing methods. RemedyAP performed a material audit of the external surfaces and found some galvanic coupling that was contributing to corrosion of the galvanised surfaces.

Coatings

Coatings act as a barrier to the environment and are usually the first line of defence against corrosion of building materials. RemedyAP provided a coating survey and identified areas requiring improvement.

Sealants and water shedding

The edges and gaps between building elements often enable moisture to creep along building interfaces causing corrosion under coatings. RemedyAP provided an audit of the sealants and identified areas requiring improvement.

RemedyAP’s scope:

Condition assessment

RemedyAP’s condition survey describes the degradation mechanisms, maintenance options, and recommendations on maintenance cycles to maximise efficiencies.

Specification for replacement of screening

RemedyAP’s CorrAssure condition assessment identified an area of significant corrosion due to galvanic coupling. RemedyAP was able to provide a construction specification for replacement and improvement of the screening to enable long term corrosion resistance.

Office building - corrosion

Maintenance schedule

The building protection systems included galvanising, coatings, sealants and corrosion resistant alloys. After 10 years of service, these systems displayed varying degrees of weathering. The CorrAssure program provided a 15-year maintenance plan that included three 5-yearly maintenance cycles. With this maintenance plan, RemedyAP provided the client with a roadmap of how to manage the building in the most efficient manner.

Standards referenced for the remedial project included ASNZS 2312, AS 4361, AS 4312 and AS 2311.

Outcomes:

CorrAssure provided the owner with a written condition assessment. The CorrAssure survey provided recommendations on items requiring immediate repair.

The CorrAssure survey provided a 15-year maintenance plan for the owner to manage future maintenance.