A free-standing glass and steel mezzanine
The 12th-century St Laurence church has been reordered to accommodate a wide range of youth ministry work. A new mezzanine runs the full length of the side aisle, between the side wall and a row of massive stone columns. The delicate steel and glass structure is selfsupporting and demountable to make minimal intrusion into the fabric and to preserve the spatial volume of the historic building.
The mezzanine floor is an open platform protected by a structural glass balustrade, with a glass-walled meeting room and a staircase at the chancel end. An additional staircase is cantilevered from the curved walls of the vestry/quietroom rotunda, a freestanding structure at the rear of the church with a bridge link to the mezzanine floor. The kitchen and servery, wcs and store are pod-like units that slot under the mezzanine floor.
The mezzanine floor itself consists of a steel frame of T-shaped beams supporting timber joists and an oak floor with underfloor heating. The beams are welded to a series of paired circular steel columns set 2.8m apart and aligned with the original stone columns. The floor extends 900mm beyond the columns on each side, supported by the tapered ends of the T-shaped beams and terminating in a semi-elliptical steel hollow section.
The original church floor is covered by a raised access floor system and oak boards.
At the rear of the church, the point loads of the mezzanine columns and rotunda are spread by structural supports resting on steel spreader plates and concrete levelling pads. Elsewhere, these are accommodated in an undercroft.
The floor voids are ventilated by perforated stainless-steel trays set along the edge and covered with loose-laid cobbles.