Highpoint. - AKT II

Location

London, UK

Client

Mace, Realstar Group

Architect

Axis Architects, Rogers Stirk Harbour + Partners (concept)

Project Value

£ 100 million

Status

completed 2017

Expertise

Structures

The scheme provides 470 mixed-tenure apartments alongside local amenities in a new public square and a 180-seat theatre; the tower block is octagonal in shape, providing the majority of plots with corner balconies, and this is partnered with a pioneering 8-storey block.

The environment was a key driver in the concept, and communal roof gardens with spectacular views, a number of green roofs and 500 bicycle spaces were incorporated from the outset to further the development’s green credentials.

A number of innovative construction techniques were considered for the tower; its repetitive, symmetrical nature gave us scope to develop a bespoke system and a high-speed construction method. The resulting framing system works holistically as all elements contribute to the lateral stability system as well as providing vertical support. An arrangement of four internal concrete blade walls provide buttressing to the central core, whilst every floor slab acts as an outrigger engaging eight perimeter blade walls which are also articulated within the façade, providing an aesthetic which is true to the structural behaviour of the tower.

The balconies extend over 4 m from the perimeter floor plates, propped by corner cables which provide the necessary damping against induced vibration. These cables then extend to the top of the tower supported by the ‘crown’, again providing a visual link between the architectural language of the development and the structural systems.

The 8-storey podium block is the product of research into prefabrication and modular construction; it was originally conceived as a timber cassette system then a precast concrete frame, but a timber approach was reconsidered, and the employment of a cross-laminated timber (CLT) construction was decided. This allowed for prefabrication that led to a rapid construction time and limited the manual labour required on site.

Since the project’s completion, we have undertaken research into the real behaviour of the building by performing validated on-site measurements on the tower. We installed anemometers, accelerometers and pressure sensors to monitor the effects of the local wind climate, with the results analysed and the findings contributing to future projects in adding further value.