Wilkinson Eyre's competition-winning Ashcroft International Business School is an elegant, open building - the key to developing Anglia Polytechnic University's presence in Chelmsford
Creating a single campus for Anglia Polytechnic University is taking a long time. It feels now, though, that a turning point has been reached. The sale of the old town centre site helped fund the edge-of-town location. Two adjoining buildings by ECD and some student housing have made a start. The approved masterplan, the opening of the Ashcroft building as both business school and campus front door, and the start on site of a student and sports building - all by Wilkinson Eyre - are together beginning to create a significant urban presence in this Essex town.
The Ashcroft is named after Michael Ashcroft, ex-Tory Party treasurer and former APU student, who donated substantially to the project. It was won in competition against Rick Mather, Edward Cullinan, Pawson Williams and Erik van Egeraat. The client was looking for something special, a statement, but also to address the immediate context of ECD's Queen's building, which used to be the campus entrance, and Sawyer's building. The original entrance via the Queen's building has been demolished and the three buildings are now connected in a 'T' formation - the left and right halves of the top bar are the Ashcroft and Sawyer's buildings, the southfacing leg of the 'T' is the Queen's building.
This formation makes the Queen's building, visually, the Ashcroft's immediate neighbour, seen from the campus entrance to the south.
It is in yellow brick, with limited openings, rather inward-looking and very different from the characteristic lightness of Wilkinson Eyre.
The design of the Queen's building, dating from 1993, was driven by a client representative seeking to meet a very low annual energy target, focused on thermal mass and controlling southerly window sizes; and all designed in one of those sixweek funding windows that can suddenly happen in academe. (Even so, the underlying energy-conserving approaches of the two buildings have similarities. ) Given the form of the Queen's building, Wilkinson Eyre has set the Ashcroft a little apart, separated by a glazed box, fronted by the curved wall of the main 150-seat auditorium. You might expect to feel crushed on entering through the shallow slot beneath, but the experience is lightened in a variety of ways. Facade glazing all around the solid makes the volume float. And once inside, the rake of the floor soffit rises away from you, now in white. You are in a large white, light, open volume spanned by bridges with glass balustrades, and ahead, a fully glazed wall looking out onto trees and the River Chelmer.
To your right, the ground-floor cladding of the Queen's building has been removed to open on to its cafe. A new entrance to the library space has been created at this level, while on the first floor the original cladding remains within the entrance volume. Dominic Bettison, the project architect, would have liked to replace this with storey-height glazing more in keeping with the Ashcroft building, but the budget did not allow it.
The walls are now rendered, and the effect is to make this internal street more street-like.
The other building-linking is done by the bridges in the entrance area. They link the Ashcroft's teaching-level corridors (floors one and two) through the entrance area to the first floor of the Queen's building and into the Sawyer's building beyond. From this elevated route, within the entrance, other bridges branch off to the front and back levels of the raked auditorium - echoes of Bennetts Associates' Hampstead Theatre (AJ 6.3.03) The entrance area can feel a little underoccupied, but it provides a sense of significant arrival and has potential for communal uses, such as exhibitions and receptions. A promised coffee area - now marked out by orange carpet - and an open-access computer area should provide added liveliness.
The business school itself has a totally glazed, southerly double-layer facade and stepped-plan, largely-glazed walling to the north, where the better views are, all set between bookends of staircases and risers clad in grey terracotta rainscreen. It is deliberately 'rational and businesslike', says Bettison. It should suit the suits. It is crisply detailed and elegantly done; a particular achievement in a contract with Contractor's Design. (There was some cooperation, though, between Wilkinson Eyre and the contractor's architect, Scott Brownrigg + Turner. ) The result was also helped by the Ashcroft subvention. Having visited several further/higher education buildings recently that have a meanness imposed by tight funding, it is good to find money well spent, both in the quality of the palette and in having a bit more elbow room.
Having opened the building to the north and south, protected by extensive blinds, rooms are arranged either side of spine corridors on the lowest two floors. Traces of outside connection are retained in these corridors on occasion, using floor-to-ceiling Reglit glass troughs as part of the corridor walling. They contribute through animation more than borrowing light from the rooms for illumination, both for the corridors themselves and also for the odd teaching room off the corridor that is totally enclosed - the faint shadows of people passing in the corridor make them feel a little less cut off.
The ground floor is mainly offices, the first and second are teaching spaces, the third is for staff and the top floor is openplan with roof terrace, for uses yet to be developed, such as large formal meetings or business events. On the 3m planning grid (6m structural) teaching spaces are for 15, 25 or 50, with one 50-seat room and one 25seat room separated by a sliding/folding partition. The original competition design included many more such partitions but they have been omitted, not just as a cost saving but also an acknowledgement of the impracticalities of constantly reconfiguring rooms to match timetabling.
Almost all spaces have a storey-height, sealed glazed wall, though to the south the large expanses of glass will be protected by blinds for a significant amount of time.
Walls are plain plastered. The ceilings have provided a challenge since the building uses TermoDeck hollow concrete planking for floors throughout with its exposed soffits (except in the corridors where a downstand ceiling masks the air feeds to the floor above). The architect was careful to keep the ceiling plane clear and to precisely align the light fittings. Subsequent installations of fire alarms and audio-visual cabling and equipment have not respected this order.
There are splashes of colour among the grey and white. For example, the entrance floor is paving slabs, and there is blue sheet flooring and the inset of orange carpet for the coffee area. The west staircase walls are yellow, with slot windows that should glow yellow to the outdoors at night.
Outside, there will be more lighting as part of the landscaping by PRP Architects.
This not only provides the building setting - a band of bark-mulched planting notionally suggesting a riverbed sweeping round to the front of the building from the Chelmer. It also begins to shape the spaces that will emerge more fully as the masterplan is implemented.
The die is cast. The university has had the confidence (and cash) to commission a building as good as Wilkinson Eyre provides to mark its future intentions.
ENVIRONMENT AND SERVICES
It is interesting to compare the two nowadjoining buildings at Chelmsford - the Queen's building by ECD with Arup and the Ashcroft building by Wilkinson Eyre with Atelier 10. The Queen's building (AJ 2.6.93, 'Energy monitoring report'AJ 9.1.97) has a substantial masonry solidity, though not with very small openings, nevertheless feeling somewhat inward-looking and protective. The client set a very tight energy target, resulting in reduced openings to the south. The Ashcroft building, apparently lightweight in metal and glass, feels much more open.
Thermally, both buildings are focused more on cooling than heating, and use thermal mass to achieve that (the Queen's building's low U-value is as much about thermal intertia as saving on its already-small heating requirement). The Queen's building has exposed concrete soffits and the toplights to windows are under BMS control for air inlet.
Ventilation and night-time slab cooling are either by cross ventilation or stack effect up through the atrium. Although the Ashcroft building is largely sealed, it uses the TermoDeck system of hollow-core concrete floor/ceiling planks, through which air is delivered to stabilise temperatures and for delivering tempered air.Both buildings are quite open to daylight, for the qualities it brings to spaces as well as its potential energy benefits. Even when the Queen's building was being designed, research was already beginning to show what hard work it is to save energy by improving daylighting.People leave lights on. In both buildings the quest for some openness leads to significant reliance on shading and glarereducing devices - the Queen's building has translucent glass light shelves to cut glare on desks as well as to reflect light on to the ceiling, and occupant-operated internal blinds. They are located between a single outer pane and double glazing, an arrangement almost as thermally-effective as external blinds (its extra cost subsidised by an EU Thermie Grant). The Ashcroft has (mostly) external southerly blinds, protected from the elements by being within a double-skin facade. Occupancy sensors switch off lights and close the blinds when the spaces are empty, with blade angles different at different times of the year to keep out direct sunlight.Perimeter light fittings dim in response to outdoor brightness.
Overall, the energy-saving means at the Ashcroft building are somewhat simpler, a lesson learnt over time about robust building operation. The environmental strategies, though, are quite similar. Appearances can be deceptive.
In detail, the Ashcroft has evaporative (adiabatic) cooling at air handling units for the air supply to floors and some refrigeration, estimated to be needed for 5 per cent of the time. The TermoDeck system is expected to be adequate even for cooling the computer suites.
There is substantial winter heat recovery, with an occasional residual heat load. The floor-to ceiling glazing is likely to create cold downdrafts in the coldest weather and local electrical heating has been set alongside the windows to counter this.The external blinds are adequate for blackout.Lighting is mostly by low-energy linear or compact fluorescents.
The reception area has natural ventilation, with roof vents located either side of the lecture theatre. The 150-seat auditorium will sometimes be densely occupied and needs more-intensive treatment than the TermoDeck system can provide. Here, the greater ceiling height is exploited, using displacement ventilation - slightly-cooled air is introduced at low velocity (thus quietly) at floor level and rises, entraining heat from people, forming a pool of uncomfortably warm air out of harm's way above head height, where it is extracted.
Effective blinds are essential to the operation of this building with its storey-height glazing.
The double wall southerly facade provides the external blinds with wind and weather protection (although blinds are internal at ground floor).The double wall is also expected to reduce winter heat loss by approximately 30 per cent compared with double glazing on its own, though at significant construction cost. As a recent report by Stephen Tanno of Buro Happold points out, the reduction in solar gain as a result of stack air movement within this open-top glazed flue is likely to be marginal. * There is a potential to use this sheltered environment for secure ventilation/night purging, but here the air supply is from air handling units on the roof.
For IT, desktop computers are generally connected for data by wireless network.Power and voice/data outlets are provided through raised floors for the working areas on the ground and third (staff ) floor, with floor trunking on other floors.No point should be more than 2m from a power outlet. The designers accept that this approach is 'relatively low-cost but it does impose restrictions on flexibility of locating desks, and especially carrels or groups of desks'. Security, public address and CCTV have been installed by the design team, but not IT nor audiovisual systems.
* Multiple Skin Facades: Experience and Projects, Buro Happold
TENDER DATE March 2001
START ON SITE DATE November 2001
CONTRACT DURATION 52 weeks
GROSS EXTERNAL FLOOR AREA 4,384m2
PROCUREMENT Amended JCT 98 with Contractor's Design
TOTAL COST £6,445,000
CLIENT BHP ARCHITECT Wilkinson Eyre Architects: James Llewellyn, Dominic Bettison, Paul Baker, Geoff Turner, Stewart McGill, Jim Eyre
PROJECT MANAGER Mace Consulting
QUANTITY SURVEYOR Gardiner & Theobald
SERVICES ENGINEER Atelier 10
STRUCTURAL ENGINEER Buro Happold
LANDSCAPE ARCHITECT PRP Architects
ACOUSTIC CONSULTANT Sandy Brown Associates
MAIN CONTRACTOR William Verry
CONTRACTOR'S ARCHITECT Scott Brownrigg + Turner
SUBCONTRACTORS AND SUPPLIERS Precast concrete floors and stairs TermoDeck; curtain walling and structural glazing William Verry Glazing; M&E services Franklins; stainless steel rainscreen CA Group; terracotta rainscreen James Taylor; profiled glass Reglit; auditorium seating Race; entrance doors Dorma; louvres and blinds Tau ras Littrow
Anglia Polytechnic University www. apu. ac. uk
Wilkinson Eyre Architects www. wilkinsoneyre. com
Mace Consulting www. mace. co. uk
Gardiner & Theobald www. gardiner. com
Atelier 10 www. ateliereng. com
Buro Happold www. burohappold. com
PRP Architects www. prparchitects.co. uk
Sandy Brown Associates www. sandybrown. com
William Verry www. williamverry. co. uk
Scott Brownrigg + Turner www. sbt. co. uk