RAU have converted an existing building into a CO2-free, sustainable office for the WWF.

Looking at the new headquarters of the Dutch chapter of the World Wildlife Fund (WWF), you are involuntarily reminded of a nature film where, the longer you look and the more the camera zooms in, the more fascinated you become by the wonders of nature, be it a cooperative ant colony, a spider spinning its web or the symbiosis between a tree and a lichen. Walking around and through this building, you discover that spaces, materials and building services are linked to one another and the surroundings by means of an ingenious, sophisticated system. And that is precisely what the WWF had in mind – a building centred around people and animals that uses low-tech technologies to achieve high-tech levels of sustainability and energy efficiency.

This overall concept began with the choice of location. WWF, which was looking for new premises to accommodate its organizational growth, opted to renovate an existing building rather than to waste a still functional structure by demolishing it. The building (a former agricultural laboratory from 1954) stands on the Schoonoord estate in Zeist, the city where the WWF headquarters were previously located. Since 1990 the organization has collaborated with landscape architect Willem Overmars on the restoration of Schoonoord, a protected nature area.

In 2002 the WWF organized an invited competition for the building’s conversion. From a field of seven practices, which included Soeters Van Eldonk Ponec, SeArch, Wessel de Jonge and JHK, Amsterdam-based RAU emerged the winners.

In their design, the centre of the existing structure is per­forated by a new, amorphous volume, the new „face“ of the WWF. This intervention simultaneously softens the strict geometry of the structure and introduces a vertical accent into the building. The open space contains the entrance – moved from the darker and mossy north side to the south side – and public areas. Visitors are led into the building via a bridge over the pond around the entrance. The raised, rectangular volume at the north side of the building has been clad with wooden shingles. It contains the meeting centre and is connected to the central space by a footbridge. The offices are accommodated in the east and west wings which have acquired new facades with Oregon pine frames and awnings, and transparent and dark grey tinted glass.

The building has a closed system energy balance. It is naturally ventilated via gratings incorporated into the facades. Eighty-five per cent of the annual energy requirements for heating are provided solely by the presence of people and the use of equipment. The heat released is stored in a capillary network concealed in the clay plaster ceiling. The (heated) water is drained off and stored below ground. In summer this water is used for cooling. The remaining 15 per cent of energy needs is supplied by a combined heat and power system that operates on linseed oil, making this the first CO2-free building in the world. Solar panels and solar boilers on the roof provide electricity and warm water.

The „sustainability“ claim refers mainly to the materials, which include responsibly logged wood with FSC (Forest Stewardship Council) certification, bamboo from Columbia and tadelakt (Moroccan lime plaster). Leembouw Nederland, which produced the tadelakt, also supplied over 400 tons of clay for plastering ceilings and walls – a good example of how natural materials nowadays can be used in a very utilitarian and sophisticated way, something this company has specialized in. Investigations were also carried out to ensure that none of the materials used was produced with the help of child labour. One example of how natural processes come together in this „architectural biotope“ is the facade of the „blob“. The architect suggested titanium – one of the most sustainable materials –but the WWF rejected this as inconsistent with the required low-tech image. It was eventually decided to use variously tinted slates made from baked river clay. This product was supplied by brick and tile manufacturer Wienerberger, which has for many years sponsored the WWF’s campaign to rehabilitate Dutch river estuaries (in the interests of better water storage) by buying the clay excavated from the river beds.

The interior, finished in natural materials and colours, blends in with the landscape. The layout is for the most part open plan and where partitioning was unavoidable, glass was used. Acoustic measures include the use of felt panels on cupboards, perforated facade panels and sound-absorbent ceilings.

Accommodation for animals living in the area is an integral part of the renovation. An existing well was turned into the entrance to a bat cellar below the car park and the bats, together the swifts, make use of the nesting boxes built into the facades. All in all, the new WWF office is a marvellous symbiosis between man and animal, building and nature.

A10, Mi., 2006.11.15

Hans Moor Architects make innovative designs based on Darwin’s theories.

Hans Moor compares the evolution of architecture to that of a plant or animal species, which is driven by mutations in genetic material. His own design method is based on Darwin’s theory of the survival of the fittest. It consists of testing and combining design variants on different levels of scale, using three-dimensional computer programs, in order to come up with the most suitable solution both from the point of view of architecture and with respect to the economical use of material, energy, money and time. Moor’s method may seem theoretical and prescribed, but his buildings are fortunately not; he always proceeds from the spatial experience he wants to create for the user.

The „Absence of light“ bridges are part of a larger commission in the Rotterdam suburb of Nesselande which will eventually contain 4500 dwellings. Half a kilometre away is another bridge that Moor built in 2003: the „Bridge of wind and water“. A water and wind installation (windmill) coupled to this pedestrian/cyclist bridge and a steel grid in the centre of the deck are intended to raise users’ awareness of their surroundings. In due course it will be joined by a „Bridge of horizon and difference“ that incorporates a covered section from which pedestrians can look out over the horizon of Lake Zevenhuizen. Moor also designed the recently completed „De Hapering“ metro station that is part of the Nesselande „transport island“.

Access to this transport island is provided by the „Absence of light“, a family of seven bridges that splits the different traffic flows into separate bridge decks for cars, cyclists and pedestrians. At the head of the family are two large bridges for vehicular traffic, on the west side of the island. The lighting of these bridges is integrated with the structure: in the evenings and at night the bridge is a trail of light that illuminates the road deck and the surrounding area. The concrete structure is perforated with a pattern of dots of varying diameter. The round holes are filled with specially developed glass light fittings containing blue LED lighting. The perforations also make the area below the bridge lighter by day and by night. The substructure is likewise designed to appear as light as possible; the slanting concrete columns all tend inwards, accentuating the horizontality of the bridge which appears to float on the water. The balustrades with their slender diagonal rails are of powder-coated steel.

The cyclist section of the bridge for slow traffic, which is next to the two car bridges, is structured and illuminated in the same way. The pedestrian section is designed as a separate zone. The deck consists of perforated aluminium sheets, interrupted every three metres by a glazed strip with integrated lighting. The other five bridges for non-motorized traffic are simpler versions of the big bridges but without the integrated lighting.

Moor’s architectural interpretation of evolutionary theory extends beyond technical innovation and economical designs. The horizontality, the everyday materials and grey and blue palette of concrete, steel and glass gives this substantial piece of infrastructure a distinct, coherent presence that is naturally embedded in the Dutch landscape.

A10, So., 2006.01.08

Julian and Cari-Janie Hakes’s partnership seems to be founded on winning competitions – the first one in 1995 when they were still studying at Cambridge...

Julian and Cari-Janie Hakes’s partnership seems to be founded on winning competitions – the first one in 1995 when they were still studying at Cambridge University, the next one in 2000, when they formed Hakes Associates. In 2004 and 2005 they went on to win two more competitions in England with their designs for the Mobius in Bristol and the Bridge of Hope in Liverpool. They are currently working on designs for two 300-metre-long cycle/pedestrian bridges in Boston (USA) and two 500-metre-long highway bridges in Kuwait. It’s starting to look very much as if striking bridge designs will become their trademark.

The Mobius Bridge design, developed in collaboration with Buro Happold, is a typical example of Hakes Associates’ style. Inspired by the endless Möbius loop, the new pedestrian and cycle river crossing is a dynamic, continuously tied structure that is physically and structurally independent of both riverbanks in order to avoid forces that could damage the adjacent buildings and archeological remains on the site. The geometry of the bridge has been carefully chosen to produce an effective structural solution in relation to the site constraints. The main span comprises a steel arch in compression, with the deck suspended by relatively small diameter hanger cables. There is a connection between the arch and the deck where the two cross over, and the deck section spans the remaining distance to the end as a beam.

This autonomous construction lends the bridge a sculptural character, turning it into a local landmark and a symbol of the regeneration of the Finzels Reach area of which it is part.

A10, So., 2005.11.20