The Whinney Mackay-Lewis Partnership
Banque Paribas' uk expansion plans required that it move to a new London headquarters building and be fully operational before the end of 1997. Whinney Mackay-Lewis assisted with the site search and subsequent analysis, with the result that the bank was able to consolidate its London operations in one 47,500m2 building at 10 Harewood Avenue, NW1, three months ahead of schedule.
Development constraints agreed with Westminster City Council and further constraints set by a previous planning consent for the site dictated that the new building had to remain within the earlier massing envelope and provide the same overall development areas in order to achieve the earliest possible planning consent.
Banque Paribas' new London headquarters replaces previous 1960s office blocks on the site, which is to the north of Marylebone Station. The office building is to the south of the site, and a new residential block, part of the same development, to the north.
The office building comprises an 80m x 80m block of five floors rising to a main parapet level of 23.5m, with two further, annular floors set back behind a roof terrace and the whole surmounted by a 26m diameter dome. Due to the substantial recession of these upper annular floors and the dome, the apparent height of the building from most view points is set by the main parapet.
A projecting three-storey bay window structure, glazed from floor to ceiling, surmounts the two-storey, ground- and first-floor base. The 3m module on Harewood Avenue is carried around the other elevations with a similar 6m bay. These projecting bays are carried up into a deep cornice at parapet level, producing a modelled, almost crenellated, skyline. Flamed limestone-clad 'buttresses' flank the entrance and turn the corners of the building.
The reconstituted stone cladding, using a range of naturally red and buff-coloured limestone aggregates and the French 'Rochebelle Rose' flamed limestone from the Macon area, gives the facade a unifying colour which relates well to the adjoining Marylebone Station and Landmark Hotel.
The long elevation on Harewood Avenue comprises two pavilions of seven 3m bays, respecting the scale of Marylebone Station, with the entrance between them formed by cutting the floors back between ground and third floors, to create an 18m x 18m-diameter, frameless glazed semi-cylindrical entrance hall, bridged over by the fourth floor. This half-cylinder, with the 4m overall diameter revolving door and its canopy as its centre and focus, also functions as a pivot to accommodate the meeting and change of axis of the orthogonal grid of the building as a whole with the oblique line of the Harewood Avenue frontage.
The entrance canopy is glazed with variously fritted glass in order to provide an element of solar shading as well as reflective illumination when up-lit at night.
The frameless clear glass screen spanning the entrance facade is supported and wind-braced by stainless-steel 'bow-string' trusses which are suspended from a 1.7m-deep plated girder at fifth-floor level. The transparency of this screen is optimised by ensuring that the stainless-steel and glass elements - lifts, lift-lobby floors, balustrading, escalators - offer minimal obstruction to view and natural lighting for internal deep-plan areas.
In order to accommodate the scale of a room plan of 80m x 35m, the dealing floors have a ceiling height of 3.5m with floor-to-ceiling windows; asymmetric 'wave form' coffered ceiling panels, set in a 1.5m square tartan grid, are paired to create a 3m visual module, with linear luminaires running along the axis of the room.
This ceiling, providing 85 per cent direct and 15 per cent indirect lighting, dimmable to 350 lux and effective acoustically, was subject to extended mock-up testing in order to achieve the optimum lighting performance and ceiling contrast to suit the demanding requirements of a high use of vdus (maximum 11 screens to a desk).
Offices occupy the third, fourth and fifth floors (but the third floor can also be converted into a dealing floor). Other accommodation includes dining and meeting rooms on the sixth floor, a 150-seat auditorium, kitchen, 'Food Court' servery and staff restaurant, and a fitness centre and dance studio.
Structural engineer's account
This development is bounded by the Marylebone Station concourse, British Rail tracks and Harewood Avenue, with both of the Bakerloo Line running tunnels passing diagonally across the site at a level close to the proposed basement excavation.
A finite-element analysis determined the extent of potential ground movements caused by the unload and loading sequences of demolition, excavation and new build, and allowed lul to accept the incorporation of a double-level basement across the whole footprint of the site.
An 800mm-deep raft foundation was selected to avoid bridging the underground tunnels, which, together with a reinforced-concrete wall facing a contiguous- piled wall to the perimeters and reinforced concrete ground- and basement- level slabs, enabled a predominantly reinforced-concrete substructure package to be let and work on site to commence before tendering the main contract.
The superstructure needed to reflect the client's desire for a minimum of columns within the trading floors, which, coupled with a high ceiling, limited storey height and a need to minimise loadings on to the relatively shallow raft foundation, led to the selection of an integrated structure and services zone solution.
The most effective option assessed was primary ubs and secondary stub girders with a composite lightweight concrete floor slab on metal decking within a typical column grid of 12m x 9m.
The structure of the central atrium is designed to allow either removal of the lower slabs or further infilling; the atrium is capped by a 26m- diameter glazed dome formed with elegant beams connected to a central ring beam.
Services engineer's account
The nature of the bank's business required an effective, flexible and reliable building-services design. From the early stages of the project, the mechanical and electrical design was reviewed in terms of its operational risks to ensure that the bank could carry out its core business under all foreseeable problems such as power cuts or equipment failure. A risk analysis (single point of failure) was carried out and later verified by certification and integrated systems tests. The design emphasis was to resource simple and proven energy-saving technologies in order to minimise operational risks.
Critical systems such as generators, ups (uninterrupted power supply), and cooling were designed to very high levels of reliability. The design includes two independent incoming electrical main supplies (one is redundant) and three high-voltage generators on which the entire building can run.
The cooling of critical areas such as communications, ups and substation rooms was carried out by using two different cooling systems supplied from different sources to maximise reliability.
The dealer and office floors incorporate air conditioning with variable- air-volume systems using multiple on-floor air-handling units which supply air via a ductwork ring main to the fan-powered terminal units. The system can operate in full free cooling mode to save energy.
A purpose-designed fully accessible ceiling incorporating the integrated lighting system was developed by the design team and Philips Lighting to provide the quality of light required for the trading desk vdus which included direct and indirect lighting.
The state-of-the-art building management system incorporating open protocol includes many standby features, but it allows for different operating modes and rescheduling of temperatures and other variables to minimise energy costs.
Investment banking contributes much to London's wealth, but finding somewhere to build a new bank has not been easy. Before the 'big bang' in 1986, investment banks tended to be smallish and housed in the grand old mish- mash of the City. The property industry was slow to understand the need for large, sophisticated buildings resulting from the growth of American, Asian and European banks seeking access to London's capital markets. The businesses went where they could find the product. That meant Salomon and Nikko to Victoria, Goldman Sachs to Fleet Street, Shearson Lehman and ubs to Broadgate, for example - not traditional banking locations. They were looking for buildings in the 10,000-25,000m2 range and they didn't want to pay the £45/square foot rent being charged at the time. The off-beat locations were cheaper because the City's sense of land value was unreal - site assembly and construction had become just too expensive. So, in 1988 Paribas went to the renovated Debenham's building in Wigmore Street, W1.
Another advantage of these locations, lost in anxiety about renouncing the folkloric grip of the City, is that they are closer to where most valued staff want to live than is the City. A West End location, particularly if near a terminus, gives the best combination of accessibility for support staff and short travel times for those living in town.
The success of Paribas in London depends on the quality of its sales and trading staff, who had become fond of the convenience and proximity afforded by their Wigmore Street location. When they needed to move, Canary Wharf was not an option. The Marylebone Station site was one of four evaluated: although the location is not traditional for an investment bank, it was one of the few places where 45,100m2 could be built to suit a reasonable time frame. And . . . it's handy for the West End.
Whinney Mackay-Lewis was able to pick up on a soon-to-expire planning permission granted to Railtrack for a speculative scheme by Michael Hopkins and Partners. This set height, massing and area parameters. It also set the basic parti of a circular atrium inside a square building on a site 80m x 120m. Paribas needed to move in by the end of 1997 because of its leases. That meant a clean run at planning permission, and a good second guess at the planners' preferences. Westminster was looking for terracotta because Marylebone Station and the hotel, which will be 100 years old in 1998, are dominantly red. Although the redness comes mostly from the Accrington brick from which they are constructed, they do have biscuit- coloured terracotta trim.
In terms of functional need Paribas has achieved a very good result, a state-of-the-art dealing machine rather than an offshore grand projet. The trading floors are terrific at 35m x 80m, allowing much planning flexibility between product groups, and the general quality of internal amenity is high without being intimidating. Although the plan is deep, Whinney Mackay- Lewis has taken pains to ensure that all remain aware of the outside, which is helped by the fact that the building is free-standing, with natural light from all four sides. Despite its two complex technical basements, the building has been economical to build at £105/sq ft for the shell and £65/sq ft for the fit-out. The typical floorplates have been well conceived for potential multi-tenant renting, although at present Paribas plans to occupy the whole. The building has been a good buy, and bought at the right time in the property cycle.
One of the most agreeable features of the building internally is a sense of spatial generosity around the public areas resulting from adaptation of the earlier Hopkins planning approval. Despite great technical skill in the articulation of the main facade on to Harewood Avenue, the building has an irredeemable feel of pink marzipan and stylistic uncertainty. String courses stop and start, as do materials, whether terrazzo, terracotta or real stone; it has the ghastly feyness of 1980s design. This is a pity for Marylebone. Despite everyone's best intentions, it has ended up a poor man's Bracken House, Michael Hopkins' 1991 tour de force in the shell of the old Financial Times building near St Paul's.
Ironically, the two buildings share an inspiration, the Liverpool office building of 1864 by Peter Ellis known as Oriel Chambers because of its pioneering use of delicate cast-iron bay windows; a building long admired and specifically credited by Hopkins as a source for Bracken House. Interestingly Jeremy Mackay-Lewis did measured drawings of Oriel Chambers for a book on Liverpool architecture. The device used at Paribas does not work, however, because it is too fussy in scale and does not play to the intrinsic properties of the materials used. Where Hopkins cherishes the contrast of High-Tech and Hi-storic in the best tradition of Victorian railway architecture, Whinney Mackay-Lewis treats the oriels as just another compositional ploy to get a vaguely historical offend-no-one facade. The result is that even though the general height and massing of the building are excellent, the main facade is really irritating, aggravated by whimsical sculpture and decorative railings which accentuate the feyness of the whole. (This is not to say that good terracotta-esque architecture is not possible; the model is Skidmore's Credit Lyonnais building at Broadgate.)
Interestingly, in the more 'important' setting of Grosvenor Square, at No 30, Whinney Mackay-Lewis has used the same oriel motif much more skilfully. There the contrast between the metallic and the masonic is stressed and articulated, rather than being elided as at Paribas.
In the end what's important in this story is that Paribas got a technically excellent building at a good price in a location that suits it. It's good for Marylebone, and good to show that banking location is more than just a tussle between the City and Canary Wharf.
Andrew Rabeneck has recently been a facilities manager for a major investment bank
Roger F Kilby and Associates
In September 1994 we received the brief requiring the building to be completed by August 1997 with a high level of price certainty. A fast- track procurement route was therefore necessary. The contract for the demolition of existing buildings was to begin on completion of the site purchase. The design of the substructure and basement had to be finalised by Easter 1995. This element was then tendered and let as a separate lump- sum contract. The remaining work above ground was split into two parcels for the office and fit-out, and for flats (not included here). With amendments to the jct standard form of contract, a satisfactory and workable format was achieved for combining the office works and warranting the contract as one.
Long lead-in elements for the superstructure (structural steel frame, precast concrete and stone cladding, aluminium windows, Planar, entrance screen and glazed dome roof, lifts, escalators, and m&e services) were designed and tendered separately. They were then passed to the main contractor at tender stage as domestic subcontractors under a lump-sum jct 80 contract with design portion incorporated, which was tendered in August 1995. Cost analysis, page 40
Two-level basement with 1000mm waterproof reinforced concrete raft, contiguous- piled retaining wall, steel frame and concrete fire encasement
Structural-steel columns and beams with Conlit board fire protection
UPPER FLOORS £29.73/m2
Generally profiled metal decking with 130mm lightweight reinforced-concrete topping; structural glass floor to main passenger-lift core
Profiled metal decking and lightweight concrete reinforced topping as slab; 60mm insulation covered with asphalt and precast-concrete paviors, stainless-steel handrails, roof garden; glazed dome to atrium with associated louvres and cleaning cradle
Steel staircases with powder-coated mild steel handrails and balustrades
EXTERNAL WALLS, WINDOWS, £150.87/m2EXTERNAL DOORS
Precast-concrete cladding of spandrel and parapet panels and fluted columns with terracotta tiles cast in; natural stone cladding on support system to corners and entrance; powder-coated aluminium double-glazed windows and escape doors; powder-coated aluminium louvres to plant rooms; entrance screen of full-height Planar glazing with bowed architectural stainless- steel supporting trusses; stainless-steel revolving-door entrance drum
INTERNAL WALLS AND PARTITIONS £128.90/m2
Drywall metal stud partitions to cores and executive dining/meeting rooms; glazed demountable partitioning system to internal offices; full-height glazed walling to main atrium
INTERNAL DOORS £41.53/m2
Lacquered high-gloss doors to offices; bird's-eye maple-veneered doors to executive dining/meeting rooms, stainless-steel framed glazed doors to cores; stainless-steel ironmongery
WALL FINISHES £43.73/m2
Natural stone cladding to entrance atrium; laminate panelling to wcs; venetian plaster and specialist painted panels to executive dining/meeting rooms
FLOOR FINISHES £75.91/m2
Generally fully accessible raised floor with carpet tiles and broadloom carpet; polished Stonite tiles to restaurant; natural stone paving to entrance atrium; marble paving to main atrium
CEILING FINISHES £79.16/m2
Generally tartan grid suspended ceilings to office areas with purpose- made wave-form panels incorporating direct/indirect lighting fittings; fibrous-plaster ceiling and mouldings to executive dining/meeting room with segmental metal-tile infills; bird's-eye maple-veneered panelled ceiling to reception area on ground-floor level
FITTINGS AND FURNISHINGS
FITTINGS AND FURNITURE 76.93/m2
Reception and security desks; entrance speed gates; trading desks for dealers; fabric window blinds; wc cubicle partitions; fittings; granite vanitory units to wcs; health club fittings; kitchen and servery equipment
SANITARY APPLIANCES £5.97/m2
White vitreous china wcs, basins, urinals, and showers for staff
MECHANICAL AND PUBLIC HEALTH £267.48/m2INSTALLATIONS
Installation compromising the following systems: chilled water; condenser water; air-conditioning distribution; smoke ventilation; wc ventilation and conditioning; fuel oil; gas pipework; diesel engine exhaust; controls; hot-water services; cold-water services; foul and rainwater drainage; sprinklers; dry risers and hosereels
ELECTRICAL INSTALLATIONS £326.92/m2
Installation comprising the following systems: high-voltage switchgear and distribution; main low-voltage switchboards and distribution; power factor correction; standby generation; ups; earthing; small power; lighting distribution and fittings; fire-alarm detection; voice evacuation and public address; clocks; telecommunications trunking; electrical services to hvac systems; lightning protection
LIFT AND ESCALATOR INSTALLATIONS £61.82/m2
Glazed scenic passenger lifts; client passenger lifts; passenger lifts; goods lifts; six escalators up to and between trading floors
SECURITY INSTALLATIONS £25.46/m2
cctv cameras and access-control system
SPECIAL INSTALLATION £65.96/m2
Structured voice and data communications cabling; window-cleaning track and cradle; document conveyor system
BUILDER'S WORK IN CONNECTION £71.49/m2
BUILDER'S PROFIT AND ATTENDANCE £25.81/m2ON SERVICES
PRELIMINARIES AND INSURANCES
PRELIMINARIES, OVERHEADS & PROFIT £133.21/m2
LANDSCAPING, ANCILLARY BUILDINGS, £2,081,914EXTERNAL SERVICES
Cost per m2 Per cent
(£) of total
SUBSTRUCTURE 161.55 8.40
Frame 73.77 3.84
Upper floors 29.73 1.55
Roof 63.30 3.29
Staircases 13.64 0.71
External walls, windows and 150.87 7.84
Internal walls and partitions 128.90 6.70
Internal doors 41.53 2.16
Group element total 501.74 26.09
Wall finishes 43.73 2.27
Floor finishes 75.91 3.95
Ceiling finishes 79.16 4.12
Group element total 198.80 10.34
FITTINGS AND FURNITURE 76.93 4.00
Sanitary appliances 5.97 0.31
Mechanical and public 267.48 13.91
Electrical services 326.92 17.00
Lift & escalators installations 61.82 3.21
Security installations 25.46 1.32
Special installations 65.96 3.43
Builder's work in connection 71.49 3.72
Builder's profit & attendance 25.81 1.34on services
Group element total 850.91 44.24
PRELIMINARIES & INSURANCE 133.21 6.93
Total 1923.14 100.00
Banque Paribas: Denis Antoine, Director uk operations
The Whinney Mackay-Lewis Partnership: Anton Jansz, Jeremy Mackay-Lewis, David Mun, Alistair Wilson, Brian Hunting, Gio Vettori, Barney Fernandez, Jesse Torres, Ian Hossack, Siew Fong, Mark Limbrick, Julian Gregson, Felix Lewis, Christina Spandagou, Tracey Kallas, Chris Cotton, Dave Brooker, Angus Holmes, Sophie Stonor, Gary Hughes, Meirion Jones, John Rachkind, Ron Baker, Chris Calcroft, Perry King, Tony Harrison, Dave O'Connor
Nick Hunter Jones
Roy Freedman, Phil Robins
Roger Kilby & Associates
SUBCONTRACTOR AND SUPPLIERS
structural steelwork Rowen, substructure O'Rourke, dry lining, dry wall partitions bdl, mesh screens Duval, demountable partitions Faram, facing brickwork North Oxford, metal sheeting Briggs Roofing, asphalt Rock Asphalt, leadwork T&P Roofing, atrium dome, entrance canopy & screen revolving door, external glazing Metallbau Fruh uk, steel doors Accent Hanson, movable walls, sliding folding doors Alco Systems, fire shutters Amber Doors, acoustic lining Decklite, door furniture, ironmongery G&S Allgood, basement door furniture Laidlaw Group, internal doors, joinery, wcs Trollope & Colls, etched glass screens Fusion Glass, atrium glazing Pluswall, automatic sliding doors, firescreens Pollards Fyrespan, raised floors Durabella, stair balustrades, metal grilles A W Jeffreys, decorationsA C Beck, hard plaster, Venetian plaster Armourcoat, external stonework, precast cladding Marble Mosaic, sealants Sureseal; Fastglobe, internal stonework Marriott & Price, carpets Tyndale, m&e services Matthew Hall, fire protection McCartney, it installation Grant and Taylor, cleaning cradles Mannesmann/Cento, escalators O&K Escalators, lifts Otis, speedgates Boon Edam, signage HB Signs, dealers' desks sbfi, boardroom table Tecno, blinds/curtains Sky Interiors, artists: restaurant Adam Craig, entrance Charlotte Mayer, lift entrance Ian Davenport, railings Sixsmiths, gates, railings cmf