The building was constructed from Canberra clay brick, with timber and lightweight concrete floors. It was rendered originally in white concrete, since painted, except for a pedestal of bricks left with their natural colour. The original roofs were constructed of flat concrete slabs with a membrane waterproofing and finished with a bituminous coating which was designed to be walked on. At the roofline, on either side of the main entrance, are large painted reliefs of the Royal and Commonwealth coats of arms. The railings on the front steps were installed after the federal parliament had left the building and were not present during its active lifetime.