New clinic for Benenden Hospital John McAslan + Partners
A glazed wall with a solar-shading screen
The new clinic wing is a two-storey building which is linked to the existing hospital on the north side; the south wall, just over 50m long, is fully glazed to take advantage of views out to the countryside and to maximise natural light. Consulting and examination rooms, reached from a central corridor, run along this wall at first-floor level; ground-floor areas are dedicated to storage and preparation of surgical instruments. Access stairs are at the east and west ends and are housed in fully glazed 'book-end'enclosures.
The new wing has a steelframe structure and precast plank floors with structural topping. The glazing comprises a curtain wall of double-glazed units fixed in pale grey polyester powdercoated aluminium mullions and transoms; they are 200mm deep so that the transoms lie flush with the floor finish.
A separate screen of continuous solar shading runs in front of the curtain wall. It consists of anodised aluminium fin blades fixed to dark grey polyester powdercoated 150 x 75mm aluminium mullions at 3m centres. At their bases the mullions terminate in curved plates which are pinned to projecting base plates. The spaces between the fin blades are calculated to reduce glare and solar gain.
A galvanised steel grille runs at the eaves to provide additional solar protection.
Each 3m bay of fin blades has a lower hinged panel to allow a ladder to be placed against the curtain wall for cleaning. The panels have stays which connect to the mullions, holding the blades out to allow the ladder to clear them. A stainless steel angle runs between each mullion to prevent the ladder from slipping.