WESTMINSTER CITY HALL Contractor: ISG Architect: BDP ³Õ²¹±ô³Ü±ð:Ìý£7³¾ Engineer: BDP Lift Overun and alterations works New steel extension to roof level BMU alterations works Structural alterations to existing toilet area levels 1-18 Formation of openings for new stairs level 17-19 Structural alterations Basement - Mezz level