Second Yaa Centre, Notting Hill, by Foster Wilson Architects
The tough, rugged aesthetic of Foster Wilson’s Notting Hill carnival centre masks the clever use of floating box construction to combat noise breakout, writes Felix Mara
The dictum ars longa, vita brevis (art is long, life is brief) could be extended to a succession of modern British performing arts buildings. Denys Lasdun’s National Theatre and, more recently, Bennetts Associates’ Royal Shakespeare Theatre transformation (AJ 16.10.10) and O’Donnell + Tuomey’s Lyric Theatre (AJS 11.10) all combine tough and resilient conceptual design with durable construction and integrity, free of the commercial logic which puts minimum investment first and optimum yield second. A small but notable addition to this lineage is Foster Wilson Architects’ Yaa Centre in London’s Notting Hill, a unique facility which provides workshops and a new multi-purpose space for carnival artists and local communities.
The Yaa Centre, which was funded by an Arts Council Capital grant, is located in an enclosed courtyard on the site of its former home, a partially demolished taxi meter factory, with existing buildings on three sides. It comprises an informal performance space; workshops for costumes, carnival floats and steel-pan tuning; a steel-pan rehearsal room; offices; arts and IT education rooms; a bar and a café. The centre complements the nearby Tabernacle Arts Centre that, with a less noise-sensitive site, is more of a performance venue. Both venues are run by Carnival Village, an umbrella organisation formed to make the Arts Council funding application, which encompasses four separate groups, each with its own aims: the Mangrove and Ebony steelbands, the Association of British Calypsonians and Yaa Asantewaa Arts, which takes its name from the queen mother of Ejisu (now Ghana) who led the Ashanti rebellion or ‘War of the Golden Stool’ against the British in 1900.
The Yaa Centre’s structural design is integral with its tectonic language of hard-wearing finishes, with power-floated concrete floors, exposed steelwork, self-finishing Holorib soffits and exposed services. Its piled raft slab protects the roots of a large plane tree and avoided the need to underpin adjacent buildings’ shallow foundations. ‘Basically, it’s like a table,’ says Foster Wilson associate Matthew Baker. It’s thicker than a typical piled slab, with no pile caps or ground beams, and its perimeter is cantilevered. It provides some acoustic separation, but much less than an isolating slab, which would have been too expensive.
‘We wanted the building to have as many natural finishes as possible, like an unprimed canvas, allowing users to imprint their own ideas,’ says Baker. Also, the idea of a common identity for the four distinct user groups was problematic. Nevertheless, Foster Wilson’s rugged tectonic language and bespoke design establishes a unique identity for the Yaa Centre. This is more literal in the case of the resin-bonded gravel finish to the entrance courtyard, derived from the geometric pattern of a traditional Ghanaian fabric. For the courtyard elevation, Foster Wilson designed a bespoke rainscreen of random 3mm Cor-ten panels, with 20mm recessed junctions, hung from horizontal arrays of concealed self-drilling screw fixings. Parallel channels restrain their bottom edges and, in order to keep the finish to the panels consistent with the recesses, the support system uses purpose-made Cor-ten channels.
To control noise breakout, rooflights are triple-glazed. Sealed double-glazed units in stainless steel outer frames are bonded to polyurethane resin infill. The tertiary glazing comprises 19mm laminated float glass in purpose-made frames with galvanised back-to-back angles.
Other hard-wearing internal elements include fair-faced blockwork, which is bush-hammered to expose its aggregate, and galvanised steel-framed screens which are double-glazed for acoustic separation. Sprung dance surfaces have battened timber floating floors with a proprietary levelling system and solid European oak boards. The scarred brickwork of the retained structure has been cleaned and left exposed. These tough finishes are balanced by brightly coloured, high-gloss laminate joinery in the café, bar and WCs. Colourful pendant light fittings also have an ephemeral quality. Apart from the stumpy brackets supporting the first floor gallery, the detailed design is impeccable.
For the purpose of acoustic separation, the steel-pan rehearsal and tuning rooms have a floating box construction with inner and outer doors, and the delivery corridor acts as a buffer where it abuts the existing mews houses. The retained structure is heavily insulated, reclad in Kalzip, and lined with gypsum board and plywood supported by acoustic hangers. Airtight acoustic construction, along with party walls on two sides and ample insulation, also boosts the building’s thermal performance. High thermal mass, shaded rooflights and a ventilation system that provides free overnight cooling keep the main spaces comfortable, and the server room and IT classroom have small variable refrigerant volume systems. Natural ventilation would have compromised acoustic requirements, although there are opening windows in the workshops overlooking the courtyard. Rooflights, PIRs, LEDs and fluorescent lamps also reduce energy demands.
Foster Wilson’s strategy involved making the Yaa Centre as energy-efficient as possible without equipping it with renewable energy sources. But there is provision to add these later, funding permitting; there are rooftop locations where photovoltaic or solar thermal arrays could be mounted, and the hot water cylinder has a secondary coil that these could connect to. The building’s intermittent water consumption is suitable for the rainwater harvesting system which serves its WCs and urinals because it allows time for tanks to recharge between events.
Foster Wilson has tackled the acoustic problems of the site and improved thermal performance. It has also provided a unique artistic, almost residential identity, closer to one of the Architectural Review’s Emerging Architecture projects than to Notting Hill vernacular, founded on a tectonic that manages to be tough without feeling utilitarian.
Start on site December 2009
Contract duration 18 months
Gross internal floor area 1,247m2
Form of contract Intermediate JCT 2005
Total cost £3 million
Cost per square metre £2,900, including external works
Architect Foster Wilson Architects
Client Carnival Village Trust
Services consultant Skelly & Couch
Structural engineer Conisbee Consulting
Quantity surveyor / CDM coordinator Appleyards DWB
Acoustic consultant Paul Gillieron Acoustic Design
Project manager David Elford
Main contractor Firmco
Approved building inspector Westminster City Council
Estimated annual co2 emissions 36.3kg/m2
Estimated annual energy consumption 118kWh/m2
Estimated annual heating & hot water load 60kWh/m2
Estimated annual electrical base load 27kWh/m2
Estimated annual lighting base load 31.5kWh/m2
Daylight factors Textile and costume workshops and art room: over 5%; Main space: 3-5%; Balcony work surfaces (estimate): >2%
Illuminance General occupied spaces: 300 lux
Workshops 500 lux
On-site energy generation None
Airtightness at 50pa 7.7m3/h.m2
Server room cooling systems and sources VRV, 25°C
Centre pane u-value of facade glazing 1.2W/m2K
External glazing Fineline Aluminium System 22, with aluminium frames and double glazing
Cavity wall facing brickwork Coleford Brick & Tile Handmade Bedford brown grey facings