To carry the gravity load of the façade and façade support structure, two 60-to-80-mm high-strength rods (depending on the zone) are hung from the mechanical room/refuge area above, with a robust steel structure designed within, to the horizontal 356-mm ring pipe beams at 4.5 meters (4.3 meters in Zones 7 and 8) on-center vertically at every strut location, including an amenity floor that uses steel bushings instead of perpendicular struts to limit lateral movement. Steel bushings move in vertical direction to allow for expected combined closing and opening movements to be largest at Zone 2, at 4 mm.