Recensie

Dutch Embassy in Amman goes for Gold

The new Dutch Embassy in Amman opened recently. Sustainable building is a priority for the Dutch government, and this building turns that aspiration into reality. The embassy in Jordan was designed by architect Rudy Uytenhaak, winner of the Dutch Sustainability Award. The aim was to achieve a gold ranking in the LEED rating system.

LEED (Leadership in Energy and Environmental Design) focuses on site development, water and energy efficiency, sustainable material use, and indoor air quality. The challenge for Uytenhaak and his Jordanian counterpart Consolidated Consultants in securing a LEED gold ranking involved integrating an existing villa into the new design, reducing the risk of earthquake damage, achieving high-insulation standards, designing architectural shading, and incorporating a range of security issues related to embassy operations.

Sustainability measures for energy efficiency, water saving and recycling, and material selection are all based on using as many local products as possible. The architectural design and detailing minimise heating and cooling loads. Daylight is the main source of illumination in the office and circulation spaces. However, reducing thermal bridges turned out to be too difficult to achieve during construction.

The first sustainable aspect in the development process was the reuse of the existing villa on the site of the new embassy. To provide enough space for the embassy’s needs, the existing villa was ‘topped’ with an additional floor. This new upper floor is bigger than the existing ground floor and therefore provides shading for the existing southern main façade.

Structural analysis revealed that a new upper floor would make the existing villa susceptible to earthquake damage. Additional columns were therefore needed to strengthen the structure, and that resulted in an impressive front elevation: a modern stone-clad colonnade. This evokes the rich architectural history of Jordan, which bears traces left by the Greeks, Romans and Nabataeans. The colonnade is also an elegant representation of the Dutch government’s hospitality, an important element of Jordanian society. In addition, the colonnade provides a pleasantly shaded space in front of the building.

The lightness of the solar shading provides a counterbalance to the heavy stone. The shades are made of cloth and refer to the local tradition of Bedouin tents. ‘Sails in the wind’ would be another legitimate metaphor. The shades are also a poetic integration of cultures for what is a highly functional element. The shading on the front and side elevations and on the roof significantly reduces direct solar heat gain in the hot Amman summer. It is designed in such a way that in the colder winters, when the sun is at a lower angle, the solar heat warms the building interior. This makes a remarkable saving in the energy consumption for heating. Thanks to the shading, the new first floor has a transparent façade. The offices behind the curtain walls enjoy clear views and daylight, and that further reduces the energy demand for artificial illumination.

To provide daylight in the core of the building, the centre of existing villa has been hollowed out. The resulting central hall connects old and new floors with abundant daylight from the skylight. The skylight can open on hot days to release excess heat and contribute to the natural ventilation in the building. This courtyard is not a new concept but can be found in traditional Arab houses.
The architect of the Dutch Embassy succeeded in combining a traditional concept with contemporary design and functionality.

A similar approach was taken to common Jordanian building methods. The façades are clad in Jerusalem stone so that the existing and new building floors are unified in material. The elegant stone detailing is based on the craftsmanship of making a building, a trademark of Rudy Uytenhaak’s architecture. The mechanical fixtures allow the stone to be reused once the building is no longer needed. This was a new concept for the Jordanian contractor.

To accommodate the ductwork and fan coils of the HVAC installation, the architect created space between the existing structure and the new ‘floating’ first floor. This provided the opportunity to make use of night ventilation. The elevation of this ‘intermediary’ space is therefore finished with grills that allow the cool night breeze to pass through, releasing the heat gain of the day and, in the process, reducing the cooling load.

The detailed design of the HVAC installation is the last step in reducing the energy demand of the building. Solar hot-water panels are integrated into the carport to provide hot water for heating the building in wintertime. The swimming pool of the existing villa is covered and reused as an underground ‘heat-sink’ to store the heating or cooling energy for the cooling system. The heat pump of the former embassy building has been transferred to the new building (LEED points for re-use) and generates cold water at night. This water is stored in the underground pool for daytime use. During the day a ventilation system is used with energy recovery to minimise the energy requirements for a comfortable indoor climate.

The photovoltaic (PV) panels on the roof produce about 12% of the electricity need, which is enough energy to power the computers in the building. And the PV panels provide shade for the roof. The sustainability aim has been pursued right down to the choice of furniture. The Dutch firm Gispen supplied furniture with an EMAS certificate. And the desk illumination is designed to meet local lighting levels.

As one of the water poorest countries in the world, Jordan places great importance on saving water. Potable water consumption has been reduced by 32% through water-saving fixtures and rainwater collection for garden irrigation. In the garden, water-efficient plants were selected and the existing trees were retained wherever possible. The front garden is designed as a representative area of the embassy. It exudes the tranquillity of the wadis found along the Dead Sea. The Dutch royal family, the House of Orange, is evoked when the orange tree in the centre bares fruit.

The overall result is an impressive new embassy building with comfortable office space and sophisticated architecture. The balanced sustainability measures have created Jordan’s first potential LEED-certified building. At the time of writing, it is only three points short of the Gold rating.
Dutch Architecture shows the best it has to offer and demonstrates sustainability across borders. Elf Mabrook*!