Council on Tall Buildings and Urban Habitat
Strata, London
Posted September 2011

Other Featured Tall Buildings

“The first building in the world with cladding-enclosed wind turbines, it sets a new benchmark in terms of environmental strategy.”
– Robert Torday, BFLS

148 m (485 ft)

36,610 sg m (394,067 sq ft)

Primary Use

Castle House Developments Ltd.
Brookfield Development Corporation
Design Architect
Structural Engineer
WSP Group
WSP Group
Brookfield Constructions UK Ltd.

Figure 1. Overall view

From the outset, sustainability has been key to the building's evolution. The developer, professional team and contractor have developed and implemented a comprehensive sustainability strategy that details all processes and procedures from project concept, design and construction to post-occupation. This holistic approach to sustainable high-rise design will prove to be very useful for the future of tall buildings.

Strata constitutes a key element in the Elephant & Castle Regeneration Masterplan. This 408-apartment development has a modest footprint which creates additional areas of public realm at ground level. The scheme also includes an adjacent five-story pavilion building that will comprise residential and retail facilities. Strata will be connected to the planned Elephant & Castle MUSCo (Multi-Utility Services Company), a community combined heating and power scheme which uses renewable resources.

The Strata has in many ways been shaped by both short and long-distance views of its form; hence the articulation and grain of its distinctive cladding are designed to both make their mark on the London skyline as well as create a strong sense of human scale that engages the public when viewed close-up.

Figure 2. Building lobby concept
Figure 3. Building exterior at night

The first building in the world with cladding-enclosed wind turbines, it sets a new benchmark in terms of environmental strategy. The use of integrated wind turbines is a visually exciting means of generating electricity for a building of this height and location. The form and orientation of the building enables the best use of the dominant prevailing south–south west wind direction. The three five-bladed, 9m (30ft) diameter wind turbines are rated at 19kW each and are anticipated to produce 50Mwh of electricity per year, approximately 8% of the building’s estimated total energy consumption.

To put this figure into context, it is enough energy to meet the total annual demand from 30 two-bedroom apartments (based on current 2006 Building Regulations). The electricity generated by the turbines will be used to supplement the landlords’ supply for the common areas of the building. The actual energy output of the wind turbines will be published after two years of comprehensive wind data analysis.

Figure 4. Integrated turbine details
Figure 5. Environmental systems diagram

The three wind turbines at the very top of the building are housed in closely fitted cowlings. As befits their nature these cowlings form complex three dimensional ‘venturi' like enclosures that help funnel air past the turbine blades, increasing local wind pressures at the plane of the blades thus increasing overall turbine efficiency. The units were assembled on the ground prior to being lifted into place as complete sections, minimizing work at high altitude. Access for general maintenance and the replacement of parts is provided via the building maintenance unit.

Each layer of the façade has been tuned to vary its performance where appropriate. Glass, the most precious and vulnerable layer, is located on the inside, with a solid aluminum panel forming the outermost layer and an intermediate zone that contains the ventilation zones and opening panels. The solid operable vents on the building’s façade allow for natural ventilation.
Figure 6. Façade looking up

Related Links
CTBUH Skyscraper Center Profile:
Visit Strata profile

iSQUARE was recognized as a Best Tall Building Nominees in the 2010 CTBUH Awards Program.
Download the Strata 2010 CTBUH Awards Book section

2010 CTBUH Awards Book

The CTBUH would like to thank BFLS for their assistance with this article. Photos and Drawings © BFLS Ltd.