Dannatt, Johnson Architects' association with the Royal Botanic Gardens at Kew goes back to its design for the newly landscaped entrance, shop and cafe at Victoria Gate in 1992. Recently, the practice has refurbished Museum No 1, which faces across the large central pond towards the Palm House. Both buildings were designed by Decimus Burton (with Richard Turner as engineer on the Palm House) and completed in 1848 and 1856 respectively, but the museum is unmistakably the plain sister: classically well-proportioned but staid and with a suggestion of domesticity that characterises the majority of buildings in the gardens.
On the exterior of the building, dja has stripped away ivy and wisteria, repaired stucco work, cleaned and repointed the brickwork and strengthened failed flat-arched windows by removing the internal brickwork and installing a precast concrete lintel tied to the external brickwork by stainless steel ties; external brickwork was left untouched. Cast iron guttering and downpipes were recovered and the roof finishes partly renewed.
The museum houses the gardens' economic botany collection, with exhibits displayed in purpose-built cabinets on the ground floor and, as in the building's original configuration, access to the two upper floors is restricted to staff. In 1881, an extension with a grand staircase was added to the rear but in 1987 the fire officer declared that a single staircase was inadequate and the museum had to be closed.
Damp accumulated in the unoccupied building causing general deterioration: plasterwork crumbled, ceilings failed and roof timbers started to rot. dja repaired floors and ceilings with metal lath and plaster and replastered walls and ceilings and door surrounds with traditional lime-sand plaster. Fortunately, the elaborate fibrous plasterwork around the 1881 stair had remained largely undamaged. The roof timbers were replaced and resin repairs were carried out where an attack from longhorn beetle had caused damage.
The refurbishment has transformed the ground-floor museum and given the building a new function as the rbg's education centre, with provision for visiting students and school children including a small picnic area to the rear; administration offices are on the second floor.
General lighting in the museum is deliberately minimal, the display cabinets themselves to act as the main light source. Hence, focussable spotlights mounted in recessed lighting tracks concentrate light on the exhibits to prevent light spillage. Similarly, the original mahogany cabinets have been restored and incorporate fibre-optic lighting. The reception desk and circular display cabinet in the entrance lobby are new, as is the American white oak flooring.
Steel powder-coated fire doors, similar to those used by dja in the refurbishment of the Queen's House at Greenwich (aj 4.7.90), have been fitted neatly into existing arched doorways and are, like the new steel stair, 'unashamedly modern'. The stair floats in a void carved out of the west side of the building, making minimal contact with the original fabric: it cantilevers off a single supporting column and has white oak treads and a stainless steel handrail; a lift has also been installed in the opposite side of the building.
Formerly, the first floor was open plan, now it is partitioned; a sliding folding screen allows staff to adapt the main education room to suit group sizes. A small kitchen and wcs have been added on the top floor. New service risers are placed at either end of the building incorporating all major services. Artificial ventilation is provided via flexible ductwork inserted into existing chimney stacks. Secondary glazing has been installed on rear windows to reduce noise from nearby Kew Road.
The project was financed by a £1.4 million grant from the Heritage Lottery Fund. Other sponsors included the Ministry of Agriculture, Fisheries and Food, the Weston Family and The Wolfson Foundation.