massa’a extension | feature stories the massa’a extension by Hatem AlShaikh, Structural The Haram Al-Sharif Extension project will increase the Holy Mosque’s inner capacity by 30% to one million worshipers while preserving the integrity of the Holy Mosque and the sanctity of the communal experience shared by millions each year. The Massa’a extension consists of four main floors including the basement, a basement connecting gallery, two additional mezzanine floors within the two top floors, and new electromechanical basements at the eastern and western piazzas. Two additional floors The two additional mezzanines - a mechanical floor for the comfort and safety of the worshippers and a speciallydesigned floor for worshipers with physical disabilities - will be embedded in the main structure of the Massa’a within the two top floors, and will have two different support systems. Inside the Massa’a, the floors are supported on columns and on either side at Safa and Marwa; they hang from the main floor above by means of steel hangers. The foundation The extension’s new foundation is designed to support a total of seven main floors - including the basement - six mechanical, and five handicappedaccessible floors accounting for any possible future extension. Construction detail Concrete slabs are precast/pre-stressed hollow core slabs, or cast in-situ solid slabs, depending on the regularity of the area and the location of the supporting beams. A 100-mm thick cast in-situ topping concrete slab is typically placed on top of the precast slabs to provide continuity over the supporting beams. The precast slabs are supported on the main precast/ pre-stressed girders supported on cast in-situ concrete columns. 05