New River Head Research Building (Thames Water)

Laboratory, research, and office building located in the New River Head site, with its main entrance in Arlington Way. Built 1936–38 for the Metropolitan Water Board by architects Stanley Hall and Easton and Robertson (John Murray Easton as designer), with builders Walter Lawrence and Son Ltd. and stone carver John Skeaping.

The building features a steel frame faced with brownish-red Himley bricks in stretcher bond (with vertically laid bricks above the 1st floor of the front block) and Portland stone dressings. The roof and floor construction employ hollow tile, and the windows are plate glass with glass brick panels. The design follows the Modern Movement manner with a long curved main axis articulated in powerful horizontal expression. An attached entrance foyer and semi-circular glazed staircase projection of strong vertical design forms the front block, set at right angles to the main axis and facing both Arlington Way and Rosebery Avenue.

The building comprises three storeys with a full basement extending only along the main axis. The curved elevation presents a 21-window range. The double-fronted entrance block faces Arlington Way with a 5-window range and five giant two-storey full-height glass-brick panels set in recess to the round-ended left-hand return wall.

On the front elevation, two-storey full-height giant brick pilaster strips rest on a stone plinth with metal casement sashes set in recess and glass brick panels set in recess to the round-ended return. Flanking steps rise to a recessed centre entrance. A moulded stone cornice sits above the 1st floor. The 2nd floor steps back slightly with short sashes to the main front and a plain brick wall to the rounded left-hand return, which displays the Metropolitan Water Board's coat of arms carved in stone relief at the centre. A brick parapet with string courses and stone coping completes the elevation.

The curved side elevation features a stone basement with upper floors containing metal casement sashes that decrease in height progressively. These sashes have stone surrounds with fluted jambs and bracketed sills to the ground-floor recessed sashes of a 13-window range. The 1st floor has ribbon windows articulated by short stone pilaster strips, whilst a stone cornice and sill band sits below the 2nd-floor sashes, with a stone string course above them. A plain brick parapet with stone coping forms the top.

The interior contains an outstanding circular cantilevered staircase with wrought-iron balusters and bronze handrail. The stair treads and hall floor are of terrazzo, lit by full-height panels of glazed bricks and surmounted by a blue ceiling over the stairwell. F. P. Morton incised a figure of Aquarius surrounded by stars in plaster and gilt upon this ceiling. Other period details include square lighting wall fittings mounted on copper backs and wood figurative relief sculpture panels above some of the doorways.

The building was erected over the site of one of the filter beds that had been installed to replace part of the Outer Pond. Easton and Robertson specialised in laboratory design following their work for London Zoo in 1933–1934. The building's north-south aspect was essential to its function. Situated within the historic New River Head site, it forms a significant architectural group with other listed buildings and is adjacent to Sadler's Wells Theatre. The laboratory represents a simple but powerful design in the modern spirit of Charles Holden or Thomas Tait.