Kings Gate and the Zig Zag Building

Two buildings are linked by a shared basement and comprise 12 storeys of office accommodation (to BREEAM Excellent); 100 residential units over 13 floors (to Code for Sustainable Homes Level 4); flexible A1 & A3 retail over three floors; a 132MVa substation; two public spaces with public seating and art work with possible connectivity to a future park at the rear; and basement parking for 156 cars.

The primary means of facade articulation is a projecting bronze anodised aluminium fin, sited at 1.5m centres on the lowest storey and bunched increasingly tightly on successive floors. As these rise, they also reduce in depth, ensuring that the level of overshadowing offered to the curtain glazing remains constant. On the residential block, the gesture is inverted. Here, the balconies by which the larger apartments address the street are screened by a field of diminutive pillars in Jura limestone. Closely spaced at the lower level, where privacy is a pressing consideration, they fan out as they rise.

Within the Zig Zag Building’s superstructure, high-quality, in-situ exposed concrete slabs were designed, including cooling coils within the flat slabs. A challenge was convincing all parties that the cooling coils could be incorporated and not clash with the PT tendons/rebar while maintaining a flat slab. This required fully designing the rebar and using physical models to prove there was ample room for all elements.