Reconstruction and extension of a public market building

An existing public market building of complex plan form, made up of two block-sections linked at basement and ground floor level, taken through reconstruction in two stages. Two new volumes are added to the second block-section: a single-storey extension with an internal stair down to the basement at −3.600 and a trafficable roof giving access to the first and second floors, and a three-storey extension carrying a lift shaft and stairs, likewise with a trafficable roof entered at +4.200. A separate small volume houses the ventilation plant. Floor area of the block-section once both extensions are joined to it is 1 755.9 m², on a site of 1.9334 ha.

Circulation and levels drove the geometry: internal stairs to the basement and to the ground floor, a lift with two stops at −1.200 and +4.200, and an external stair up to the trafficable roof. Storey heights step through the extensions — 4.10 to 3.00 m in the single-storey volume, and 5.20 m and 2.70 m at ground, 2.30 m at second and 3.90 m at third floor in the three-storey one. Roofs are flat with internal rainwater drainage. The main entrance is reached over a landing and steps served by a multi-level ramp for people with reduced mobility, with two further secondary entrances.

Envelope: sandwich panels with a basalt mineral wool core 100 mm to the walls, R = 3.08 m²K/W, three-layer 150 mm sandwich panels to the roof, PVC windows with two-cavity insulating glazing at R = 0.64 m²K/W. Existing foundations are retained. New foundations are formed at −2.400 on a compacted sand bed with new beams over the openings cut through the retained structure. Produced using AutoCAD and Revit.