After two decades of abortive proposals to repair the two bespoke curtain walls of Great Arthur House, John Robertson Architects was finally selected by tender to replace them. Dating from 1959, the aluminium and glass system was leaking and not performing to modern thermal standards. The project included the wholesale replacement of the curtain wall system with a near facsimile giving higher thermal performance, and strengthening to the concrete frame to receive the heavier replacement walling.[9] The cost to leaseholders is approximately £95,000 per flat.