The Steeldeck platform was the creation of Philip Parsons, a physics graduate turned set-builder, who built a company that became renowned for creating the scenery for a generation of shows in London. But, during an inevitable downturn, he kept his staff employed with a side project: building a better rostra.
The design took a truss-like outer steel framework with central cross pieces, and topped it with 3/4” ply, backed by foam for acoustic damping and fireproofing purposes. In each corner, a mounting post for a standard scaffolding pole leg to get the height you needed; use angled legs and you could create rakes. The standard size (8ft x 4ft) is the same size as a standard plywood sheet, so no material is wasted. It will support up to 7.5kN/m2 - stronger than many of the concrete floors it finds itself standing on.
Two powerful testaments to that original design are that it is still going strong, and has hardly changed since.

Steeldeck
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