Garden of England
In its design of an office building at the Kings Hill business park in Kent, Richard Partington Architects has created a workplace that reflects the local vernacular without becoming a pastiche Richard Partington Architects was formed three years ago. Its first major project to be completed is 17 Kings Hill Avenue. At the outset, Richard Partington hoped that, despite the rigid preconditions of office planning, he and his team would produce a civilised workplace and a well-crafted building with 'a presence' - a modest but well-judged set of ambitions.
The site is on one of the main arteries at Kings Hill, a business park-cum-residential settlement complete with primary school, ASDA supermarket, pub, golf course and acres of woodland set on a former Battle of Britain airfield. To the north, lies the M20 motorway linking London to the Channel Tunnel, the North Downs and the upper and more industrial reaches of the River Medway. To the south are the hopfields and orchards of the upper Medway valley and the Weald of Kent.
Here in this prime location, Rouse Kent, an affiliate of Liberty Property Trust, one of the best-known American developers, has been steadily working during the past 10 years creating a private world of an extraordinarily high quality. It is not exactly an exemplar of sustainable development: land is used generously, pedestrians are nowhere to be seen and, despite the quiet rural location, air conditioning is quite common in the larger buildings. An unmistakable air of prosperity pervades the place.
The business park contains three types of building: three-storey 'landmark' offices, including the neighbouring Charities Aid Foundation building (AJ 17.10.96), designed by Nicholas Hare Architects (for whom Richard Partington worked for several years); two-storey offices; and single-storey B1 buildings. With their hipped roofs and fake pediments, the second group are, despite their pavilion form, generally undistinguished and lacking in presence. Like several of the single-storey buildings, they sometimes suffer from being sited below road level - as if hiding away on the semi-rural site.
Seen from the roadway, 17 Kings Hill Avenue sits well on its plot, has a clear and distinctive form and an instantly visible front entrance and visitor parking area. Its 'presence' derives partly from its 'grounding' above road level and partly from its dominant roofs with their finely detailed oversailing ends. Partington's design responds to the developer's request for a building that reflects the local vernacular - evident, at this scale, in barns and oast houses with their massive roofs and brick and weatherboarded walls.
The brief was for a naturally ventilated building of 3,250m 2on two floors. Rouse and its architects always start by studying alternative plot ratios, building forms and car parking and access arrangements. Here, the preferred option was a U-shaped building with a south-facing courtyard, access from the north and the bulk of the car parking (for staff ) away from the road, on the western boundary. The east wing, parallel to Kings Hill Avenue, is partly screened by generous planting, the entrance side has a large old walnut tree to one side and the courtyard opens onto a large orchard.
Two great open gable ends, inflected gently towards each other, embrace the approach to the entrance doors. The inflection is derived from the 10infinity splay between the two wings. Passing through the doors in the large glazed screen, one enters into a double-height space in which an open dogleg stair rises to a first-floor gallery with a gently curving edge, the setting out of which also derives from the building's splayed form. Inflected towards the north east, the gallery offers a wonderful view over the trees in the foreground towards the North Downs on the horizon.
The floor plans exploit to the limit the direct travel distances for means of escape - thus providing the maximum floor area for the minimum number of escape stairs. Four tenancies are possible on each floor (the building currently has a single tenant). Each wing is 15m wide, with natural cross ventilation through top-hung windows with highlevel vents for use in winter. Radiators counter cold down draughts. The plan form suggests many possibilities: the entrance section linking the two wings should offer an orienting view straight into the court; the areas to each side of the entrance hall (to which they have access) are an obvious location for meeting rooms; and the spaces adjacent to the six French windows are natural sites for 'break out' and coffee areas.
Sadly, none of these possibilities have been exploited by the tenants, who have occupied the building at a higher density than expected. But the failure to pick up the architect's 'clues' seems too fundamental to be attributed to overcrowding. Radiators are obstructed for their full length, wonderful north-facing corner windows are obscured by venetian blinds and perimeter occupants seem to disregard the ventilation needs of those furthest from windows.
The courtyard recalls Christopher Alexander's A Pattern Language. This recommends open rather than closed courtyards (pattern 115) and south-facing outdoor spaces (105). This courtyard is indeed a pleasant space both to be in and to look out onto. But, with a tree towards its open end and some paving outside the coffee area at its closed end, it could become both livelier and more useful.
Concrete columns support a flat slab at first-floor level and a timber truss roof above. Raised floors provide space for power and communications cables. Suspended ceilings, 2.75m above floor level, use a standard American 2ft (600mm) grid and accommodate category 2 light fittings. The perimeter columns are set out at 1.5m centres, so the ceiling and column grids coincide at every other column. The column grid does not relate to brick dimensions so, every 3m, there is a remarkablyinconspicuous cut 3/4 brick. The steeply pitched roof was meant to incorporate a continuous glazed ridge, lighting the central zone of the first floor below. This was subsequently abandoned but part of the roof void (in the link between the two wings) has been adapted as a record storage area.
The facades have a depth, whether of eaves overhang or ground level pier recess, that marks the building out from its peers.
The Sussex Findon Yellow stock bricks have gently rolled joints, the roof is natural slate (from Canada), the timber boarding is western red cedar and the windows are good quality powder-coated high-performance aluminium units. The brickwork is occasionally modulated in a gently telling way - around the French windows and at the corner cantilevers. The latter are supported by the galvanised and painted channel lintols and some brick course reinforcement.
Much of the credit for the quality of this building must go to Rouse's staff (led by construction director Nick Condon) and the framework that the company has evolved over many years for design and construction development. The overall budget is fixed but, within this, using a pool of experienced and committed contractors and subcontractors and a prime-cost form of contract, the entire design and construction team constantly searches for more effective ways of detailing and construction. This process continues right into the contract period and, rather than being clawed back by the client, savings made on one element can be used by the team to improve the quality of another.
At £759 per square metre, this building represents very good value. Adaptable, well detailed and well constructed, it benefits from Rouses' decades of experience in commissioning and maintaining such buildings (visible, for example, in the astonishing quality of the WC areas); from the consultants' imaginative skills (as in the discreet external lighting of the building and its setting); and in the quality of its assembly (particularly evident in the brickwork). Partington's ambitions for the building have been amply fulfilled, and the practice has now been given an opportunity to develop its ideas in a similar building - this time including interior fit-out - for Jupiter Asset Management elsewhere on the Kings Hill business park.
Structure The main structure of the building is an in situ reinforced concrete frame supported on mass concrete pad foundations.A 300mm thick flat slab at first floor is supported by circular columns in the centre of each wing and by rectangular columns around the perimeter which are built into the cavity wall to give a flush face without protrusions.
At first floor, the central columns are omitted and the roof, a simple softwoodtrussed rafter structure, spans 15m supported by steel perimeter ring beams at eaves level which are exposed externally.
This detail extends around the entire building at eaves level and is repeated at ground-floor lintel height, where steel channels are built into the brickwork cladding.
Plant towers at the end of each wing are contained within an exposed steel frame supporting double cantilevered trusses and an open-boarded soffit to the main pitched roof.
Above the central core a steel frame and permanent metal formwork slab provide additional storage and plant space at second-floor level within the roof space which is supported by a steel frame in this area.Stability is provided by reinforced concrete walls within the core at the end of each wing.
The main feature stair in the reception area is open-tread steelwork with no central post which relies on the stiffness of steel channel stringers and an RHS half-landing beam for stability.
Costs based on final account SUBSTRUCTURE FOUNDATIONS/SLABS £43.75/m 2Isolated pad foundations and wide strip footings, concrete ground slab and dpm SUPERSTRUCTURE FRAME £35.31/m 2Reinforced concrete frame UPPER FLOORS £48.61/m 2Reinforced concrete flat slab floor cast in situ ROOF £71.59/m 2Canadian slate roof with timber trusses and supporting steelwork, insulation and single-membrane flat roof over plant areas STAIRCASES £13.45/m 2Prefabricated steel staircases EXTERNAL WALLS £57.16/m 2Facing brick insulated cavity walls with cedar cladding to gable ends, and polyester-coated metal louvres to plant areas WINDOWS & EXTERNAL DOORS £59.46/m 2Aluminium double-glazed windows and doors.
Aluminium curtain walling system to reception area INTERNAL WALLS AND PARTITIONS £30.00/m 2Concrete block partitions to cores INTERNAL DOORS £8.96/m 2Maple-veneered solid core doors with hardwood frames and architraves INTERNAL FINISHES WALL FINISHES £4.83/m 2Dry lining to blockwork and decoration FLOOR FINISHES £36.29/m 2Medium-grade fully accessible raised floor with carpet tiles to office areas.Ceramic tile on screed to core areas and reception CEILING FINISHES £27.99/m 2Exposed grid suspended ceiling to office areas.
Plasterboard to reception including decoration FITTINGS AND FURNISHINGS FURNITURE £8.15/m 2Proprietary WC cubicle system including vanity tops and mirrors SERVICES SANITARY APPLIANCES £2.78/m 2White ceramic fittings with disabled fittings DISPOSAL INSTALLATIONS £22.85/m 2Above-ground drainage and waste pipework and drainage below building WATER INSTALLATIONS £7.78/m 2Hot and cold water supply pipework including insulation SPACE HEATING/AIR TREATMENT £45.69/m 2LPHW system with radiators and over-door heater to reception ELECTRICAL SERVICES £74.50m 2Electrical switchgear, lighting and power. External lighting LIFT AND CONVEYOR INSTALLATIONS £6.70/m 2Thirteen-person hydraulic passenger lift PROTECTIVE INSTALLATIONS £10.12/m 2Fire alarm, lightning protection, gas detection system and petrol interceptor alarm BUILDERS'WORK IN CONNECTION £6.03/m 2General builders'work PRELIMINARIES AND INSURANCES PRELIMINARIES, OVERHEADS AND PROFIT, INSURANCES £136.88/m 2 CONTRACT TYPE Two-stage JCT 98 TENDER DATE September 1999 COMPLETION DATE August 2000 CONTRACT DURATION 44 weeks TOTAL COST £2,796,478 GROSS EXTERNAL FLOOR AREA 3,685m 2CLIENT Rouse Kent ARCHITECT Richard Partington Architects: Richard Partington, Madeleine Adams, Colin Davis, Nick Bethune, Ewa Maciejewska QUANTITY SURVEYOR Davis Langdon & Everest STRUCTURAL ENGINEER Price & Myers SERVICES ENGINEER Rybka Battle MAIN CONTRACTOR Wates Construction SUBCONTRACTORS AND SUPPLIERS concrete frame and external works Bretts;
timber trusses Kent Timber; brickwork Rowe;
windows/cladding Leay (Kawneer Specialist);
roofing Cobsen Davies;
structural steel Allslade;
staircases Crane & Rowbury; fit-out Pieri;
mechanical and electrical Skanska; louvres Kingfisher; raised floors Quilligotti; ironmongery Higrade; lift Otis CREDITS Rouse Kent www. kings-hill. com Richard Partington Architects www. rparchitects. co. uk Davis Langdon & Everest www. davislangdon. com Price & Myers www. pricemyers. com WEBLINKS EXTERNAL WORKS LANDSCAPING, ANCILLARY BUILDINGS £431,990 Soft landscaping, car parking, access road, footpaths, bulk earthworks, external drainage and statutory authorities Cost summary Cost per m 2Percentage (£) of total SUBSTRUCTURE 43.75 5.77 SUPERSTRUCTURE Frame 35.31 Upper floors 48.61 6.41 Roof 71.59 Staircases 13.45 External walls 57.16 7.53 Windows and external doors 59.46 7.84 Internal walls and partitions 30.00 3.95 Internal doors 8.96 1.18 Group element total 324.54 42.76 INTERNAL FINISHES Wall finishes 4.83 0.64 Floor finishes 36.29 4.78 Ceiling finishes 27.99 3.69 Group element total 69.11 9.11 FITTINGS AND FURNITURE 8.15 1.07 SERVICES Sanitary appliances 2.78 0.37 Disposal installations 22.85 3.01 Water installations 7.78 1.03 Space heating and air treatment 45.69 6.02 Electrical services 74.50 9.82 Lift and conveyor installations 6.70 0.88 Protective installations 10.12 1.33 Builders'work in connection 6.03 0.79 Group element total 176.45 23.25 PRELIMINARIES AND 136.88 18.04 INSURANCE TOTAL 758.88 100.00 Costs supplied by Derek Vernon and Marc Carn of Davis Langdon & Everest