The Cathedral is built in concrete with a Portland stone cladding and an aluminium covering to the roof. Its plan is circular, having a diameter of , with 13 chapels around its perimeter. The shape of the Cathedral is conical, and it is surmounted by a tower in the shape of a truncated cone. The building is supported by 16 boomerang-shaped concrete trusses which are held together by two ring beams, one at the bends of the trusses and the other at their tops. Flying buttresses are attached to the trusses, giving the cathedral its tent-like appearance. Rising from the upper ring beam is a lantern tower, containing windows of stained glass, and at its peak is a crown of pinnacles.