Jason Thomson, General Manager Get to know PACT’s GM Jason’s history with PACT goes way back…
TYPE OF PROJECT
A mixed-use development commissioned by the Anglican Church Diocese of Perth, Church House comprises six floors of A-grade commercial space featuring offices and meeting rooms, a two-storey basement car park, ground floor lobby and café. It was designed by Kerry Hill Architects.
We navigated a complex site, particularly during the early stages of construction. The proximity of existing heritage-listed structures surrounding three sides of the building site (St Georges Cathedral to the west, the Anglican Diocese Deanery to the south, and the Public Trustee building to the north) posed significant challenges when constructing the double basement.
We drew upon innovative construction methods to preserve the structural integrity of these 150-year-old heritage- listed buildings. This included adopting a ‘top-down’ construction methodology – a complex and highly innovative construction method that required the perimeter basement walls to be constructed using a ‘diaphragm’ wall system. These walls were constructed first to provide support to the retained soil and adjacent buildings. Next, the ground floor slab was constructed and tied into the diaphragm walls to provide structural stability. The excavation of the soil was completed under the protection of the slab, before each floor was finished and tied into the walls as the excavation proceeded towards the lowest level of the basement.
The top-down construction method helped to:
- Keep the adjacent Pier St laneway open and free of construction traffic.
- Reduce the risk of structural damage to surrounding buildings.
- Enable the early construction of the super-structure.
- A curved glass facade to the south, east and west elevations with feature stone to the northern elevations: Constructed over seven floors, the building has been designed to draw in natural light, connect with outdoor areas and engage with the surrounding Treasury Precinct. The external façade required a high degree of planning and coordination to accommodate the design intent.
- The roof structure of Church House was also curved to match the glass facades. Structural steel was designed using a segmented RHS steel section cut and welded at multiple locations to allow for the geometric requirements of the roof design. These were fabricated off site using highly advanced CAD shop drawing designs.
- The entrance lobby consists of an entry atrium ceiling of level/class 5 quality polished plaster with recycled Ironbark feature veneer screening.
FEATURES OF DEVELOPMENT
The base of the Church House building features carved stone and platforms that restore the ground plane around the Chancel of the Cathedral, providing pedestrian connections through the newly constructed Cathedral and Treasury precinct. A curved engineered facade wraps around two sides of the structure, offering unimpeded views to the Cathedral and Stirling Gardens.
The remainder of the building provides A-grade office space fitted out to impeccable standards. The building achieves both a 4 Star Green Star rating and 4.5 Star NABERS rating, ensuring that it operates efficiently and productively while also guaranteeing lower operational costs.