Specifier's choice:School of Slavonic Studies, UCL
University College London (UCL) occupies the north end of the University of London's Bloomsbury campus. The broad generosity of William Wilkins' main building on Gower Street, with its portico and grand stairs leading down to the great quadrangle, gives no hint of the tight-packed nature of the accommodation squeezed into the streets behind.
It is here, in a Bloomsbury block just north of Gordon Square, that Short and Associates' new School of Slavonic and East European Studies is coming out of the ground. Its site is one of the last plots available to UCL: until work started at the end of last year it was the loading bay for UCL's chemistry school, just south of the Bartlett architecture school.
Access to the chemistry building had to be retained, so the ground floor of the new building consists of a wide D of buildings, surrounded by a roofed road accessed via the big arches on either side of the street facade. On the four floors above, the perimeter of the back of the building follows the same semicircular line as the road. A lightwell, in plan triangular with rounded corners and centred on the same midpoint as the semicircle, punches down through the five floors. Its glazed base provides light to the basement library. Ground, first and second floors are also library space, and the two top floors are arranged with perimeter staff offices surrounding an open office area around the western sides of the light well On the eastern side, facing the street, is the facade block. Four storeys high to satisfy planning restrictions, this is either a roomdeep facade or, as the architects prefer to describe it, a very thin building on the street frontage. It pays a kind of respect to the surrounding late Regency terraces in terms of eaves height and the use of brick, but its elaborate (and functional) cornice, the brick colonnade across the top floor, the swooping rows of windows at ground and first floor levels and the massive array of rooftop brick 'chimneys' all unmistakeably mark it as an Alan Short low-energy-consumption building.
One of the benefits Londoners have is that the general temperature of the metropolis is always a couple of degrees higher than the rest of the country. But that fact, plus the effect of global warming, is bad news for energy-conscious purists. It means that at the extremes of temperature in what is known as the London heat island, there will always be a need for supplementary mechanical heating or cooling - in this case in the form of chilling coils high in the light well for hot summers, when the nights are too hot to allow adequate night-time cooling. The way the Short building's air conditioning (in its wider sense) works is focused on the central lightwell. It is entirely glazed with motorised opening panels run by a building management system (BMS). Its top is 'glazed' by a doubled circular array of ETFE inflated cushions (in the form of a CND badge) tilted to meet local sightline rules.
At the bottom of the light well, between the basement library level and the ground floor, there is a 1m deep zone that acts as the main plenum for incoming air. It takes air from the front of the building and at the sides, warms it slightly and releases it into the enclosed light well. Sensors all over the interiors tell the BMS which lightwell panels to open, and the air moves into the surrounding spaces. Bookshelves excepted, half these floors are open all the way to the perimeter, and the air flows naturally across to a series of thin but wide ducts, triangular in plan, which are actually part of the semicircular perimeter back wall. Every second one of these vertical ducts is glazed, with fixed glass on the outside and openable glass panels on the inner face. On the third and fourth floor, where cellular offices are arranged around the perimeter, there is a stud and plasterboard sight screen, open at top and bottom, creating a corridor, but allowing air to move freely up to the office walls.
Because they are also acoustic labyrinths, these walls are unusually thick. Although there are some impediments in the form of the screen and the labyrinths, the flat slab soffits, free from beams and downstands, aid the ready movement of air from the lightwell to the perimeter duct. At roof level the ducts change shape and become the stubby brick Alan Short towers, here 1.3m square.
In the hottest part of summer, the process will be reversed, with air drawn in to the light well at high level, and chilled by coils and drops to form a column of cool air, which is then drawn into the building. Because the outside air is likely to be hotter than air from the building, thus stopping the stack effect, the architects decided to dump the waste hot air down rather than up the ducts Working with a project manager Once UCL had decided to develop the chemistry department loading bay, its estates department ran a beauty contest for the new building - whose preliminary brief had no special sustainability baggage attached. Short and Associates assembled a design team with structural engineer Martin Stockley Associates and services engineer Environmental Design Partnership.
Their collective pitch was for a specifically energy conscious building and, following a qualitative short listing followed by indicative proposals and a fee tender, the team won the job. The estates people at UCL like to work with a project manager, in this case Turner and Townsend, which also came in as quantity surveyor and planning supervisor.
Following an OJEC call for potential contractors, a shortlist cull and then competitive tenders against a bill of quantities, and comprehensive rather than summary drawings, Wilmott Dixon Contractors was appointed under a GC/Works/1 contract - the public service equivalent of a standard JCT contract.
The role of project manager was clearly defined in the appointment contracts and referred to in the main contract. It involved reporting to the client and issuing payment documents and generally managing the contract. Whiteley says that in this arrangement: 'The architect retains a central role in the development of the brief and, in understanding what the client wants, develops the scheme through the design and the technical processes.' During construction, matters to do with the resolution of design issues are referred to the architect, as are such things as agreeing alternatives to items specified in the National Building Standard.
Short & Associates uses NBS. Whiteley says: 'You can choose how tolerant you are going to be about contractor suggestions for alternatives. Generally we work with the client to allow them but what we try to do is insist that the contractor provides full technical details so we can assess the alternative.
On other contracts it can be a bit of a game in getting this information out of them.' Some items in this contract were not negotiable. One was the brick - a machinemade stock from Chesham-based H G Matthews supplied by Taylor Maxwell, which also supplied the reconstituted stone.
The paving for the entrance is specified as a very small, 50mm square Marshalls paver laid in sand. The paving to the ground-level road will be a variety of sizes of Marshalls Tegular concrete pavers. Whiteley says:
'They're economic and they look a bit like setts.' The external skin of the rear wall is a louvre-profile, horizontally spanning steel system, specifically from Architectural Profiles, which is tied back to the slab edges.
The system incorporates a built-up steel inner wall, which forms the inner face of the perimeter ducts.
In some cases, such as the curtain walling to the light well, the architect specified generically. So, Whiteley says: 'We specified W20 and W40 curtain walling sections, and Crittall came up with the best tender bid.' In some cases the client established its own non-negotiable rules. For a number of items UCL, an experienced, professional client, has its own lists of preferred suppliers and subcontractors from which the main contractor could obtain competitive bids, which is how Thyssen Krupp achieved the lift contract.
Although the main contract was based on comprehensive drawings, there were some elements that the contractor designed.
Whiteley says: 'There were two levels. One was where we identified some contractor design elements such as the metal cladding to the rear elevation and a couple of specialist glazing areas such as the glass floor to the light well. The second level comprised installation and fabrication drawings, on which two of the three members of the design team would comment.'
Greening the roof An unusual element in the specification was the single-skin Rubberfuse rubber roofing for the main roof at the rear, which will be supplied and laid by Richardson Roofing.
Whiteley says: 'It's much greener than PVC, and we are using it as a single-ply warm roof.
It's common in other parts of the world and is very UV resistant.' Rubber sheet roofing is not exactly common and Whitley speaks of the process of discovering green building products. He says: 'There are initial ideas about appearance and longevity, and then you do a bit of analysis and refine the search from other criteria such as sustainability and renewability and so on. But then there's another question about how, when you don't know about it, you go about finding it. And so you rely on the body of knowledge in the practice.' The roof to the very thin building at the front has been designated as Rheinzink, and the roof structure is an all-timber affair.
Whiteley says: 'There were some medium spans in the roof structure, and the options we considered were a steel frame with timber joists or a completely timber structure with flitched knee joints', used along the cranked wall/roof behind the elaborate cornice on the street block. The decision to go with timber was made for reasons of structural consistency, in order to use sustainable materials, and because it involved only one trade package.
The big ETFE doubled pillows at the top of the triangular lightwell make up a circular plan, and there is a 'collar' whose quite complex geometry sorts out the transition from triangle with rounded corners to what is actually a 24-sided polygon. Internal glass partitions are a contractor design portion and, as we went to press, the architect was waiting to hear more. And, for once, the architectural ironmongery is not d line but from the FSB range. Mind you, FSB comes from Allgood and in Short's London office the FSB catalogue just happened to be sitting next to the d line catalogue: someone had been eyeing the traditional solution at some time.
Computer logic The practice uses VectorWorks, the former Mac-only MiniCAD, whose big selling point is that it makes it easy for traditional drawing board people to go digital. For example, you can do drawings at whatever scale you like rather than having to work at a scale of 1:1.
As Whiteley points, out it deploys a different logic from AutoCAD, and is more like real drawing. Although the industry standard is AutoCAD, the practice had no problem with remaining loyal to the Mac badge or with reading and writing files: the engineer Martin Stockley Associates, for example, uses MicroStation. Needless to say, the performance of the air movement was analysed on computer - although that did not preclude physical fluid modelling of the extremes of a London summer.