Former Cardiff and District Western District Sewerage Pumping Station.

Yellow brick with red brick dressings, banding and eaves cornice; stone kneelers and copings, slate roofs with glazed ridge ventilators, small pane metal glazing. Facing Penarth Road, main block has six round-headed windows with red brick arches. Thin pilasters flank the 3 right-hand window bays and are carried up above the eaves as chimneys. To R, lower block with gabled end. Below main block, modern extensions imitating its style and materials.

Left end wall has 1 large and 2 smaller round-headed windows. Above the large window is a lunette window with a pediment above this (with oculus), flanked by chimneys. Similar treatment to R end, but 2 windows with lunettes above doorway (L), and 2 windows (R). To rear, pair of attached blocks at right angle, in similar style, 5 blocked windows to NE; gables facing SE each have group of 4 windows at upper level. To SW, attached lower parallel range with 3 arched windows and red brick chimney, and lower block with 3 camber-headed windows.

1907 date stone on W corner of S elevation, inaccessible at inspection.

Main block has steel roof trusses, glazed brick dado, terrazzo floors; travelling crane. Rear blocks have steel roof trusses.