1515 Douglas St - Rotunda Roof

Crowning this Class A office building located across from Victoria’s City Hall, is a 20m diameter atrium roof structure.

The roof is seven-storeys above the ground floor and consists of six radial ‘boomerang’ shaped glulam beam-columns, connected by a 3m diameter steel ring beam in the centre, with 30mm tension rods below each.

RJC presented three different designs for the atrium roof structure for the architect and owner’s consideration, including constructing scale wooden models of each.

Due to the unique nature of the structure, and as part of the design process, a number of scale models were constructed to study form and stability.

RJC designed all the connections and then worked with the fabricator to incorporate their proposed alternate for the glulam-to-glulam connection at the beam-column bend.