Rothschild Foundation, Windmill Hill. Aylesbury, by Stephen Marshall Architects
Stephen Marshall Architects’ ranch-like archive for the Rothschild Foundation takes its cue from its rural setting and excels at craftsmanship. Photography by Richard Bryant
Engineering and craftsmanship are sometimes regarded as antithetical: engineering, the pragmatic and technocratic time and motion expert; craftsmanship, the pipe-smoking ‘it’ll be ready when it’s ready’ hermit devoted to quality. You could extend this juxtaposition to a distinction between the grand visions of the beaux arts and William Lethaby’s Arts and Crafts world of ‘brown bread and dewy mornings’. But you forget these polarities as you approach Windmill Hill in the rolling Chilterns countryside. The 25-metre beam that frames the view of its entrance courtyard sits comfortably with its pitched roofs and oak-clad west facade.
Designed by Stephen Marshall Architects for the Rothschild Foundation, the original owner of the surrounding Waddesdon Estate, the building complex opened to the public earlier this month as an archive and study centre with supporting offices and storage. ‘You need to look to America to find a similar philanthropic trust,’ says Pippa Shirley, head of collections at nearby Waddesdon Manor, which was built for Baron Ferdinand de Rothschild in the1870s. Windmill Hill augments the estate as a centre for study and debate in fields ranging from the arts to the environment and horticulture. It also houses the manor, estate and family archives, along with the foundation’s contemporary art collection.
‘When we first came on board, this was a dairy farm,’ says Stephen Marshall. Although it had long since ceased operation, Marshall retained one of the original buildings as part of a courtyard complex that, in its organisation and footprint, is not unlike the original farmstead. ‘We didn’t just want to drop in an alien object beside the farmhouse,’ he says, and the new building, which houses the archive office, matches and rhymes with its rustic neighbour by aping its terracotta ridge tiles. Something resembling a new-build Ticinese barn on the west side of the courtyard contains the archive stores, and a glass and zinc reading-room block forms its north range. To the north of this, a two-storey rendered office building completes the entrance courtyard.
Marshall has tuned in to the agricultural qualities of the genius loci and shown great sensitivity to the surrounding countryside. ‘The most important thing was to maximise the views,’ he says, and the new structure frames these precisely. But the complex’s bold concept and its abstract qualities are anything but picturesque - more like an American ranch. Its Roman scale and lintel-free giraffe doors bring to mind earlier work done with Marshall’s former partner Alfred Munkenbeck, including the Roche Court Sculpture Gallery in Salisbury, which Shirley says was ‘a big pull’ when Jacob Rothschild and architectural critic Colin Amery were assessing Marshall’s competition entry.
Structurally, there’s a lot going in these generous, barn-like buildings. The reading room roof comprises ‘two huge trusses made of wood that just lean against each other,’ says Marshall. ‘Then you simply infill the gaps to get the grid.’ Reinforced concrete end walls resist lateral and torsional forces from these trusses and provide support with minimal assistance from intermediate steel axles, which are so slender that they are concealed within the thickness of the door leaves. Subtle.
Deep verges to the overhanging eaves express the depth of these trusses, and large diagonal channels in the zinc rainscreen roof cladding reflect the primary module of these coffer-like diagrids. Although this feature resembles the roof of a nearby Victorian hotel, Marshall explains that it is not a forced reference.
On the north side of the reading room, a screen of cantilevered vertical oak posts provides a sense of containment and helps reduce solar glare from the west. Marshall compares this to screens in agricultural buildings that protect livestock from the wind but also provide ventilation. ‘We wanted it to look like a piece of sculpture, not tacked-on.’
Jacob Rothschild encouraged Marshall’s passion for bespoke craftsmanship and high-quality materials. ‘He is the most down-to-earth bloke, who knows about hammers, screws - everything. We were asked to design every element.’ One of the first things you notice about the reading-room block is the entrance door handles. ‘We had them specially made and had to buy dies to get the right shape.’ Then there’s the polished basalt and oak floors, procured from multiple suppliers. ‘You’ve no idea how difficult it is to get a hardwood floor. There’s no one person. I went to see one supplier in Amsterdam - and it still didn’t work.’ All timber finishes are English oak. ‘We’ll probably give it three coats of oil and at that point we’ll just see what happens.’ Natural render would have been prone to drying and cracking on the windswept site, and Marshall specified elastomeric insulated render,using chalk blocks to form flash-gaps.
Arises are sharp. ‘Apart from concealed roof details, there are no metal pressings,’ states Marshall. ‘Many contractors will say, “You won’t be able to tell the difference”. Of course you can!’ Cut stainless steel sheet, used for sills, jambs and skirtings, are consistently thick. This level of craftsmanship issubsidised by sustainability pioneer Max Fordham’s remarkably low-tech services design. In his frank but urbane Glaswegian way, Marshall gets straight to the point: ‘It’s intentionally primitive. Many buildings have a huge bit of kit on the roof the size of a double-decker bus, but I don’t think thatworks.’ Windmill Hill is naturally ventilated throughout. In the reading room, through-ventilation is provided by concealed, low-level slots linked to timber shutters at one end and a projecting stainless steel window with vents in its cheeks at the other. Overhanging roofs and high-performance glass reduce solar gain.
With a 1.5-metre thick wall build-up, the archive store is one of the largest naturally cooled facilities of its type in Britain. ‘The thing about this is that it’s got no moving parts at all,’ says Marshall. And because it is divided into small, four-hour fire compartments, there is no need for sprinklers. Shirley does not regret the lost opportunity for a large barn-like space. ‘It’s my favourite bit,’ she says. With similar ingenuity, the cost of the large reflector pools is offset by the omission of a conventional water supply for the fire brigade on the isolated site.
With so many clever ideas and details, you might question whether Windmill Hill’s simple conceptual design goes far enough, and if it all comes together convincingly. There are awkward moments. The aerial view reveals the elaborate range of materials and the rather bare landscaping. But, as Marshall notes, ‘with time, the building will get slightly greyer, and it will feel like it’s in a hollow with trees all round’. At present, it’s best to experience Windmill Hill sequentially - this is where its true synergy lies. But because it takes risks, it also occasionally fails; the massive trestle-struts in the reading room are a logical continuation of the diagrid, but look a little raw.
In this conceptually simple but sophisticated synthesis of craftsmanship and engineering, Marshall has arrived at something similar to the more recent work of Hopkins Architects, by a very different career route. The similarity to Hopkins’ hostry and refectory at Norwich Cathedral is particularly striking. Perhaps the Weimar-era German architect Heinrich Tessenow was right: ‘The simplest form is not always the best, but the best is always simple’.
Start on site June 2009
Contract duration 21 months
Gross internal floor area 1,610m2
Form of contract/procurement JCT SBC 2005 with two-stage tender process
Total cost £6.3 million (excluding landscape)
Cost per m² £3,900
Client The Alice Trust
Architect Stephen Marshall Architects
Structural engineer Thornton Tomasetti
M&E consultant Max Fordham
Quantity surveyor Selway Joyce
Lighting consultant Speirs and Major
Landscape designer Mary Keen / Landscape Design Agency
Main contractor Kingerlee
CDM co-ordinator Andrew Goddard Associates
Estimated annual CO2 emissions 29.9kg/m2