It has a massive concrete dome 43m in diameter, with an oculus at its centre.
The dome has an oculus to provide air and light to the hall.
The curved form is pierced at the same time by an oculus and surmounted by a square tower built in timber and covered with slate.
The transept has a gable decorated with urns and a finial, and it contains an oculus.
Below the spire, there is an oculus that admits light into the main level.
Fenestration consists of rectangular windows with granite sills and lintels along the north and south profiles, with an oculus in the gable apex.
Broad overhanging eaves set off the next section, the base of the cupola, with a shingled face and oculus.
The lead-plated copper installed in 1959 was replaced with stainless steel and the cupola from that renovation removed, to replaced with the current oculus.
