Commercial Road, No. 4 Gasholder

Gasholder, 1895 for the Sunderland Gas Company designed by Samuel Cutler. Circular plan with a wrought iron guide-frame and stone in-ground tank. The guide-frame comprises 26 shallow I-section rivetted lattice standards braced by lattice girders. The girders wrap around the uprights in a continual helix to produce a rigid diagrid structure. It conforms to the distinctive Cutler type 39 gasholder. The joints between vertical and diagonal members are formed by gusset plates with concave edges; several of these at first floor level bear an oval plaque embossed with the words 'Cutler's Patent erected 1895 Guide Framing'. A horizontal box lattice girder runs around the top of the frame, the guide rails being carried above it as a series of tapering finials and there are radial rollers on carriages of linked reinforced plates. A later, full-height metal staging is attached to the exterior of the frame.