Wildscreen@Bristol by Michael Hopkins
Michael Hopkins and Partners has broken the mould of leisure architecture for Wildscreen@Bristol, creating a coherent link from docklands heritage to a vital new quarter
One of the interesting effects of the National Lottery is the notion of public institutions. It is not just the dull but worthy edicts about equal access and opportunities; it is also forcing challenges to the received nostrums on public demand, latent potential, built heritage and the relationship between different activities. It is unthinkable now to have a leisure facility without shop, cafe and restaurant, and not just to ensure revenue.We don’t want sackcloth and ashes with the message of the rain forests.
Despite its trite name, Wildscreen@Bristol reflects the positive side. A few years ago the city council put two and two together and made slightly more than four. It had a large chunk of former dockland very close to the centre, and the prospect of money from the Millennium Commission to sort it out. Using the site required imagination on several levels: how to work with the remaining buildings - a few industrial relics and a splurge which Sir Philip Dowson designed for Lloyds Bank - but, more importantly, what sort of facilities to put there.Delving into Bristol’s cultural resources (a must for the Millennium Commission, especially when they have potential for education) uncovered the BBC’s wildlife unit, a wildlife photography festival and, of course, a legacy of scientific achievement which can be summed up in one word, Brunel. Engineering meets biology.
Nothing in the canon of leisure architecture says that all these activities have to be conjoined and there are no formal or typological precedents. The resulting Wildscreen@Bristol designed by Michael Hopkins and Partners, alongside Chris Wilkinson’s Explore@Bristol, had to invent a new vocabulary within the restrictions of existing buildings.
Wildscreen combines a 350-seater IMAX cinema with ‘black box’exhibition space and a botanical house alongside the listed former leadworks, while from Wilkinson’s inscrutable glass box protrudes an ‘Imaginarium’ which resembles a sphere made from two geodesic domes.
Added to these architectural challenges was the city’s urge to animate the whole quarter with a square; quayside cafes in refurbished warehouses and new buildings; a bridge over the dock to the Arnolfini Gallery; and a Bill Pye water sculpture at the dock head.The key to making these combinations work lies in their contribution to public space.
Diehards who think that cultural quarters should either be like Washington, Brasilia or the South Bank, and populists who would have everything in the Disneyland mould will be equally disappointed. Bristol has attempted something harder and more heterogeneous than either. Its chances of success would have been higher if Gunter Behnisch’s scheme for a performing arts centre had come to fruition, but the attractions drew 5,000 people per day during the recent half term; and many more have walked through the district.
Running on the spiral of life panel in Wildscreen, but also neatly describing the urban and public agenda, is Charles Darwin’s comment ‘from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved’. It might apply to Hopkins’ architecture, too, which has similarly evolved into richer and more complex patterns. Hopkins’ seeming start point is to confront the most obvious problem and make it a virtue: retaining the wings at Bracken House, allowing the flytower to break through cylinders at Glyndebourne, or making a feature of the air circulation systems which have such an impact on the exterior of Portcullis House.
At Wildscreen, the essential formal problem was to incorporate the linear leadworks and the cylindrical IMAX.Hopkins’elected to put the IMAX at the furthest end of the site, leaving a wedge shape for the rest of the accommodation; a brave move, given the elements which had to be fitted in and especially given the fluidity of the brief and displays which evolved during the design.But it does bring an architectural sensibility to what otherwise become a fruitless stand off between the preservation lobby and exhibition promoters.
Although fixed in shape by history and technological and seating requirement, both the leadworks and IMAX have scope for adaptation.Part of the leadworks has been converted into a shop, with a new steel frame providing a regular edge for the fabric canopy over the foyer.
The canopy covers a ‘street’, with doors at either end. It leads to an undercroft beneath a concrete shell supporting the botanical garden, with the ‘black box’spaces on either side, and into the IMAX foyer, a neat, two-storey space curving around the auditorium.
IMAX may prescribe the shape of the auditorium but that has not stopped other architects making them into glass cylinders or floating space ships. Hopkins matches its rational form with rational construction: solid, loadbearing brick with concrete padstones to mark the concrete beams. In fact, the only dose of irrationality is presenting a closed cylinder to the city centre.One almost longs for the outer wall to open after a showing of the Ascent of Everest or Secrets of the Pharoahs, to reveal Pye’s fountains or the not-terribly-improved traffic flows - following simulation with something visceral. Hopkins did recognise the anomaly and proposed a display screen on the outer wall, which would certainly present a less closed face to the centre.
Using a canopy as an entrance and to resolve some potentially awkward junctions is typical Hopkins and, perhaps, the beginning of a typology for public buildings, where functions which require certain forms make a deliberate counterpoint to forms which derive from construction.
But Wildscreen director Anne Finnie’s feeling that the undercroft’s architecture stresses the entrance to the IMAX to the disadvantage of the displays questions whether space and form alone - some kind of combination between architecture parlante and functionalism - could create both the images and patterns of use for a new institution. Signage might help here.
As the brief was fluid, the architecture inevitably had to take a lead, and it is not every day that someone asks for a tropical rainforest above an interactive zoo.
While the architecture of the IMAX was constrained by preconceived form, Hopkins had a freer hand in creating a route into and through the botanical house.Emerging from the black boxes containing displays and exhibits which were in the hands of exhibition designers, visitors enter the botanical house almost on top of the main entrance, allowing for re-orientation.
A serpentine path winds upwards through the rain forest, with brightly coloured butterflies and momentarily disconcerting (plastic) snakes lending an air of authenticity.Using ETFE, rather than glass, Hopkins sacrificed some transparency but was able to minimise the structure, making the interior almost like a tent.
The route weaves in and out of more black boxes before bringing visitors back to the undercroft.It is quite a journey, enough to stimulate children at least to take some interest in their wider environment.There is also a roof terrace and education facilities.
It is possible to raise all sorts of quibbles.One might question the whole idea of making a tiny slice of rain forest in a city centre.
And although Hopkins’ design wisely allows for separate operation, the extension of the IMAX repertoire to show more than the present fare of natural history films might undermine the premise of a single institution.
In the end, though, what Bristol wanted was a leisure quarter in the city centre, a collection of facilities rather than a coherent grouping. The convenient affinity of the buildings afforded by Lottery is more a magnetic field than a glue, and the pulses and dynamos of urban life might exist in a state of flux around them.
Minimal alterations were made to the Grade II-listed leadworks, although a lean-to roof of flitched steel beams spanning onto universal columns was added to extend the accommodation.
The stretched PVC-coated polyester fabric canopy is held in position using push-up masts and flying struts and pull-downs. A similar stretched canopy is used on the roof terrace over the exhibition spaces.
The circulation spine is formed by a reinforced concrete shell with ribs to limit longitudinal expansion. It was cast without using formwork. The reinforcement, bent to the shape of the vault, was supported while a thin layer of sprayed concrete was applied. Once the concrete hardened this had sufficient stiffness for the temporary supports to be removed, which allowed access for spraying the full thickness of the vault.
The two helical staircases consist of individually cast concrete steps supported by using a small amount of torsional restraint at the wall, and transferring load through the inter-lock of the steps as an axial thrust to the ground level. The joint between steps is rebated to allow the transfer of these horizontal forces as well as the more normal vertical forces.
The roof of the botanical house consists of ETFE foil cushions, inflated to give good structural and insulation properties. They have similar Uvalues to triple glazing and good solar control properties which can be modified to suit specific needs. They are unaffected by ultra-violet light and do not become brittle or discolour over time.
The cushions are supported by a grid of pre-tensioned cables. This grid is attached to a ridge cable, which in turn is restrained along its length by two masts. Above the east and west glazed walls of the botanical house, curved trusses, warped in three dimensions, provide the fixed perimeter for the cable-net and support the glazing. The use of ground anchors in tension and the glazing mullions as compression members resolves the forces from the cable-net.
The walls of the IMAX theatre consist of two layers of masonry, physically separated to reduce sound transmission and avoid problems of relative movement. The internal ‘box’ structure is restrained laterally by the external drum, which has load-bearing masonry walls.
The roof of the drum is a series of trusses arranged radially around a central hub. Three-dimensional computer modelling allowed us to make use of the dome effect of the pitched trusses to reduce bending and hence steel weight in the roof. The trusses are supported on the external load-bearing brickwork. A concrete ceiling suspended from the roof provides acoustical insulation.
A series of steel bridges consisting of a precast glass-block and concrete deck supported by specially designed compound steel beams span between the IMAX theatre and the electronic zoo. The electronic zoo consists of a 9m grid coffered slab supported by reinforced columns.
The main floors of the electronic zoo are concrete waffle slabs which allowed large floor plates of up to 11m in span to spread their load onto the perimeter supporting masonry walls.
The external envelopes of both the exhibition building and the theatre are load-bearing brickwork bonded with hydrated lime/cement mortar.
Costs based on final account
GENERAL WORKS £16.17/m2
GENERAL WORKS £5.51/m2
FOUNDATION/SLABS £100.69/m2 General piling works and reinforced concrete slabs
SUPERSTRUCTURE FRAME £58.27/m2 Structural steel works, reinforced concrete columns and beams
UPPER FLOORS £127.59/m2 Reinforced/precast concrete floors
ROOF £177.40/m2 Metal roof, green roof, fabric canopy, ETFE cushion with blind and waterproofing to flat roof
ROOF LIGHTS £11.50/m2 Glazed roof light and ‘fritted’ double glazing
STAIRCASES £27.59/m2 Precast concrete staircase, stainless steel balustradings
LINK BRIDGES £14.12/m2 Structural steel support, handrails and balustrading
BOTANICAL HOUSE RAMPS £14.83/m2 Structural steel support, handrails and balustrading
EXTERNAL WALLS £218.76/m2 Facing brickwall, structural glazing and concrete wall
WINDOWS £38.16/m2 Double-glazed windows and metal louvres
EXTERNAL DOORS £21.83/m2 Laminate glass sliding doors and timber doors
INTERNAL WALLS AND PARTITIONS £116.08/m2 Blockwall, WC cubicles, concrete wall, spray concrete tunnel, internal glazing shop front and plasterboard
INTERNAL DOORS £57.69/m2 Timber doors with high-quality ironmongery
WALL FINISHES £53.40/m2 Plastering, wall tiling and painting works
FLOOR FINISHES £44.18/m2 Carpet tiles and vinyl flooring on raised floor and terrazzo tiles
CEILING FINISHES £13.39/m2 Plasterboard ceiling and general painting works
FITTINGS AND FURNISHING
FURNITURE £11.67/m2 Seating, kitchenette unit and bar unit
SANITARY APPLIANCES £7.78/m2 High quality sanitary fittings
DISPOSAL INSTALLATIONS £7.97/m2 General soil, waste and vent pipe and rainwater down pipes
WATER INSTALLATIONS £35.54/m2 General hot and cold water system and botanical house water system
HEAT SOURCE AND SPACE HEATING AND AIR TREATMENT £253.71/m2 General heating and ventilation system and botanical house air conditioning and heating system
ELECTRICAL SERVICES £89.78/m2 General power and lighting
GAS INSTALLATIONS £2.17/m2 General gas installation
LIFT AND CONVEYOR INSTALLATIONS £14.55/m2Passenger lifts and disabled access lift
PROTECTIVE INSTALLATIONS £17.93/m2 General fire and lightning protection system and general cabling for PA , security and alarm
COMMUNICATION INSTALLATIONS £2.45/m2 General telephone and television cabling
BUILDER’S WORK IN CONNECTION £49.74/m2 General holes, opening, plinths, metal supports, lifting beams and exhaust
PRELIMINARIES AND INSURANCES
PRELIMINARIES, OVERHEADS AND PROFIT 241.06/m2 Preliminaries, construction manager costs and M&E commissioning
LANDSCAPING, ANCILLARY BUILDINGS Separate contract
Cost per m2 Per cent of (£) total
DEMOLITION 16.17 0.87
ALTERATION 5.51 0.30
SUBSTRUCTURE 100.69 5.44
Frame 58.27 3.15
Upper floors 127.59 6.89
Roof 177.40 9.58
Roof light 11.50 0.62
Stairs 27.59 1.49
Link bridge 14.12 0.76
Botanical house ramps 14.83 0.80
External walls 218.76 11.82
Windows 38.16 2.06
External doors 21.83 1.18
Internal walls and partitions 116.08 6.27
Internal doors 57.69 3.12
Group element total 883.82 47.74
Wall finishes 53.40 2.88
Floor finishes 44.18 2.39
Ceiling finishes 13.39 0.72
Group element total 110.97 5.99
FITTINGS AND FURNITURE 11.67 0.63
Sanitary appliances 7.78 0.42
Disposal installations 7.97 0.43
Water installations 35.54 1.92
Heat source, space heating and air treatment 253.71 13.70
Electrical installations 89.78 4.85
Gas installation 2.17 0.12
Lift and conveyor installations 14.55 0.79
Protective installations 17.93 0.97
Communication installations 2.45 0.13
Builder’s work in connection 49.74 2.68
Group element total 481.62 26.01
PRELIMINARIES 241.06 13.02
TOTAL 1,851.51 100.00
Costs supplied by Davis Langdon Everest
TENDER DATE 11.2.98-7.4.99
START ON SITE DATE 9.3.98
COMPLETION DATE 3.4.00
CONTRACT DURATION 108 weeks
GROSS INTERNAL FLOOR AREA 7,502m2
CONTRACT TYPE Construction management
TOTAL COST £13,890,000.00
ARCHITECT Michael Hopkins and Partners
PROJECT MANAGER Symonds
QUANTITY SURVEYOR Davis Langdon & Everest
STRUCTURAL AND SERVICES ENGINEER Buro Happold
CONSTRUCTION MANAGER Bovis Construction
DEMOLITION CDC Demolition
SUBSTRUCTURE AND CONCRETE SUPERSTRUCTURE Dean Dyball Construction
MECHANICAL AND ELECTRICAL WORKS N G Bailey & Company
SUBCONTRACTORS AND SUPPLIERS botanical house waterproofing and green roof Gorvin Roofing; structural steel Thomas Steelwork; precast concrete John Graham (Dromore); precast floor Luxcrete; spray concrete Spray Concrete; brickwork Ferson Contractor; leadwork structure Downend Builders; glazing English Architectural Glazing; metal roof Richardson Roofing Company; wall finishes and joinery Ultimate Finishing Systems; soft floor Tyndale Carpets; fabric canopy Architen; ETFE cushion and blind Vector Special Projects; architectural metalwork Glazzard (Dudley); painting decoration Alfred Bagnal & Sons (West); seating Race Furniture; passenger lift KONE Lifts; disabled lift Gartec; botanical house ramps Cromwell Classic; hard floor Zanetti & Bailey; roman blinds Levolux; environmental controls and heating Climate Controls
Michael Hopkins and Partners www.hopkins.co.uk
Buro Happold www.burohappold.com
Davis Langdon & Everest www.davislangdon.com
Bovis Construction www.bovislendlease.com
Climate Controls www.climate-controls.com
Ultimate Finishing Systems www.ufs-ltd.co.uk