The sleek concrete and timber mosque in Sydney

Clay Technology magazine
26 Sep 2019

Australia’s Punchbowl Mosque, with an eye-catching concrete domed ceiling, is nearly complete after 20 years of work.

The Punchbowl Mosque in Sydney, Australia, is an ambitious project initiated by the Australian Islamic Mission (AIM). It has a concrete vaulted ceiling and a plywood dome in the main prayer space.

Building of the mosque was finished in December 2018, and design work on interiors is currently underway. Carpets were laid in July 2019 and additional work to the platform used by the Imam during sermons is yet to be completed, AIM Administrative Officer, Hanadi Afyouni, told Clay Technology.

After procuring three plots of land, construction of the concrete and timber mosque, designed by architecture firm Candalepas & Associates, was carried out in three stages.

A two-storey basement car park was stage one, followed by the mosque construction, and lastly erecting several community buildings.

A concrete choice

The concrete type and specifications were confirmed with Boral, a Sydney-based manufacturer and supplier of building and construction materials. A high-quality white concrete was selected due to its low-shrink, early strength and high durability, according to Candalepas & Associates, in the publication, Angelo Candalepas: Australian Islamic Mission – the story of the Punchbowl Mosque.

Low shrinkage was especially important due to the number of concrete pours needed to make the ceiling in the main prayer room, which has an intricate design consisting of 102 recessed quarter spheres.

As part of the tender negotiations with construction company Infinity Constructions, it was decided to make a model of the roof on-site to help cast the quarter spheres, or muqarnas.

In the architect firm’s paper, Candalepas & Associates Senior Associate, Adrian Curtin, wrote that the builder conducted several tests before settling on the moulds of fibreglass for the formwork, used to create the muqarnas, which were placed in seven rows on both the north-western and south-western sides of the main prayer space. Every quarter sphere muqarna measures 1,500mm-wide, 750mm-high and has a 33mm diameter ‘cast-in hole’ in the centre which lets natural light into the room.

‘These cast-in holes were utilised during the construction of the mosque roof as additional bracing for she-tie bolts, with a permanent PVC tube embedded into the formwork and plugged with a Perspex cap externally where it pierced the roof sheeting. The semi-circular flat front face of each muqarnas was set-out to taper down to a 120mm tip in order to allow for a single N16 steel reinforcement bar and adequate concrete coverage at this point,’ Curtin stated in the paper.

After construction, the domes were embellished with calligraphy of the 99 names of Allah.