[WORKING DETAIL 24.07.08] Slate rainscreen facade with recessed balconies
The three buildings that make up Bauman Lyons Architects’ The Terrace are distinguished by their external facing material.
The building that faces Grantham Street is the only one clad in slate. This steel-framed, four-storey building has hollowcore concrete plank floors with structural screed topping and a pitched slate roof. On the south facade, above a ground floor of blockwork, the walls are of steel studwork lined on the outside with insulation, impermeable breather membrane and a rainscreen of 40mm thick rectangular slate panels.
The slate is detailed to read as an extension of the roof plane; this is emphasised by the use of narrow vertical joints and wide 50mm horizontal joints between panels. To reinforce the horizontal nature of this facade, balconies are recessed behind the rainscreen and their slate-clad balustrades act as an extension of it.
The slate panels are fixed with under-cut mechanical anchors to a proprietary aluminium fixing system of brackets, horizontal rails and vertical rails which are generally storey height and fixed back to the structure. At each recessed balcony the slate rainscreen panels are fixed to a 120 x 120mm steel angle frame, backed with cement-bonded particle board. Occasional panels of toughened glass are used for the balustrade. The balustrade handrail continues beyond as a sill to adjacent windows. The balconies are lined internally with iroko boards and structural columns within them are clad with cementbonded particle board.