This was a challenging project requiring four extremely large Barrel Vault Gantrys and one main Dome Gantry.
All the Gantrys were (as is generally the case) of bespoke design in mild steel sections and all more than 20m in length. The Barrel Vault Gantrys we curved to echo the roof profile and extended with a horizontal cantilever which supported a telescopic ladder. The Ladder incorporated gas operated pistons to automatically lift the ladder clear of lower roof pipework and could then be pushed down and locked to allow the operatives to alight from the Gantry. Two of the Gantrys could be aligned to allowed full access over the barrel roof.