The 20 Martin Place project consisted of a complex refurbishment of an existing 1970s commercial tower. This was stripped back to a steel skeleton and rebuilt to create a signature 20-storey A-grade office tower incorporating a new high-performance façade system and achieving sustainability targets to achieve a 6-Star Green Star Office As Built rating.   Built was initially involved in an early contractor involvement phase where investigation works were undertaken, full-scale mockups were facilitated, alternate design and construction details resolved together with value management reviews undertaken.  The works included the removal of all asbestos in the building, alterations to the existing steel structure, demolition of existing floor slabs, cores and services. The replacement of the façade, services and the creation of a three-storey retail podium were all part of the works.  A primary challenge was the demolition of the asbestos-contaminated façade and concrete slabs in order to reveal the steel structure. The works amounted to surgery on a large building in the centre of the densely populated Martin Place. The methodology adopted allowed the demolition of the upper floors while lower level works were carried out comprising demolition and excavation for new foundations for the new core.  The installation of new services and façade incorporates the latest energy efficiency initiatives. The façade was to be bespoke in nature to reflect the prime location in Martin Place. Further consideration was also needed for the structural, thermal and acoustic performance incorporating high-end materials selections requiring each component of the glass façade to be custom made and engineered. This resulted in more than 100 new ‘dies’ being created to extrude the aluminium components of the façade.   The standard of finish was high and consistent with the creation of new A-grade office space. Overall, the works were well executed and demonstrated a high level of skill to achieve the final result.