Metsec Purlin Division has supplied its light gauge galvanised steel purlins for the roof of Plymouth University's new faculty of Art.

The roof structure presented a number of challenges due to its complex shape and load. Unlike standard 'square' buildings, the roof incorporated seven different roof planes including a major trapezoidal shape, a triangular section and an exposed vertical feature wall.

Using the Metspec 10 structural design program, Metsec engineers successfully designed a solution based on a combination of butt and sleeved systems to allow for the range of irregular shapes. Metspec 10 also enabled engineers to select optimum purlins by weight of spans and structural loadings with integrated snow and wind loading.


Wind loads were calculated in accordance with a wind study report conducted by BRE. Wind pressures were measured on a mock-up model during tests to generate design wind loads. The wind loads were considerably varied due to the overall building shape, from a maximum wind pressure of 2.39 kN/m2 and a maximum wind suction of 3.84 kN/m2. The roof has also been designed to withstand a maximum snow drift load of 2.39 kN/m2.

Purlin Division Marketing Manager Mark Evans said: "The project presented a number of challenges not least because the wind loading was twice, and at some points three times, more onerous than what we normally work to. We are delighted that everything went smoothly."

Metsec were contracted by Rowecord Engineering Limited.