Portal Buildings, Silvertown Tunnel

The team’s contribution has been developed within a site of immense scope and complexity and has been designed in the knowledge that the tunnel will affect how millions of people move across the city

Our aim, therefore, has been to design buildings of strong, architectural presence for what is, on the whole, a below ground addition to London’s landscape. The northern Silvertown portal in Newham acts as the main services and workspace building for the tunnel operators. The southern portal at Greenwich operates as a secondary back-up facility. dRMM have developed a shared visual language linked by characterful forms; a simple, high quality material palette while the detailed design of each portal responds to the individual building use and context. The designs minimise the need for foundations, using the tunnel structure to provide support.

The buildings are recognisable as the threshold to a significant piece of infrastructure, acting as markers for Silvertown and North Greenwich, places in progress which will continue to change over the time these structures are in use. Green roofs planted with the same species found in the wider landscape scheme help connect the buildings with their surroundings.

The building can deliberately see, and be seen, from all angles – a 360-degree lookout point. Its distinct shape, hand formed on site from lightweight copper, fans out giving variation and life, up close and from a distance.  The upper floors house workspaces and tunnel management facilities. The ground floor has the main entrance, circulation space and staff facilities. Within the operations compound, the adjacent building houses the essential tunnel maintenance and operation equipment. Linking all the portal buildings is the use of Staffordshire Blue brick.

Its undulating shape becomes a boundary in itself; part of the public realm through the avoidance of fencing. This building provides operational continuity, alongside administrative offices and plant rooms. The brickwork achieves a striking chain link effect with double bullnose bricks laid in a Flemish bond, used in this style here, and in the pair of buildings at Silvertown.

Prefabricated offsite, the steel structure is lifted by the colour choice of bright yellow. This is combined with an open mesh treatment to the sides enabling the pedestrians and cyclists to both see out and be visible, thereby avoiding a sense of enclosure. Protected but not sealed off from the environment.