Ebury Edge is a temporary work and community space at the heart of Westminster, providing affordable workspace and retail units, a cafe, community hall and public courtyard, with timber providing a key element of the scheme.
As part of the redevelopment of Ebury Bridge Estate, Westminster City Council was keen to give the local community an immediate sign of the regeneration. The concept consists of two buildings: a two-storey building with a timber frame workspace and retail at ground floor and a singlestorey block containing a cafe and community hall, open internally to an asymmetric pitched roof using prefabricated timber trusses.
A scaffold frame links the buildings and will provide the substrate for greenery to grow. As it is a 'meanwhile' proposal, the design needed to be efficient, offering good value whilst enabling simple construction and a future reuse. Fully electric and designed to be demountable and be reassembled, buildings had sustainability at the inception. Arup provided SMEP plus civils, fire, environmental and acoustic engineering services, with the design developed from concept to tender in just two months.
Westminster Council's regeneration of the Ebury Bridge Estate, just south of London Victoria, will see the renewal of existing housing blocks and the creation of 750 new homes on the premises on Ebury Bridge Road. Local businesses and entrepreneurs were encouraged to join the new pop-up, which features affordable workspaces and a multi-purpose courtyard.
The Council consulted extensively with the residents to gather ideas and thoughts on how this space could work to drive the design. The superstructure of the workspace is formed of timber floor and roof cassette supported along by timber stud walls. The stud walls bear onto a grillage of steel beams which spans between shallow mass concrete strip foundations. The ground floor timber cassettes create a naturally ventilated cavity beneath the slab. Because of the large retail glazing at ground floor, fours steel portal frames have been carefully inserted in the cross direction of the first and last of the seven double storey units, which are all tied together.
The design allows for flexible future reconfiguration including the option for units to be relocated individually. It will be possible to retrofit a steel or glulam portal frame in each of the units, providing future flexibility and reducing upfront embodied carbon.
Timber trussed rafters form the community building’s roof. These bear on to timber stud walls sitting on steel beams, similar to the workspace units. The café and community hall, split by the toilet and utilities central block, are large open spaces which provide flexibility of use. Due to the presence of legacy obstructions in the ground and to the limited budget, shallow foundations formed in mass concrete was chosen for their simplicity and for the possibility to crash the concrete to be reused for the piling mat of the future main scheme multi-storey buildings.
However, since the area used to be marsh land, it is possible that settlements might occur with time. To accommodate this movement, the steel ground frames sit on removable packers, which will allow level adjustment by jacking up and adding packers. A detailed review of the fire strategy with Building Control/the fire brigade enabled the omittance of a sprinkler system and minimised the area needing fire compartmentalization treatment. Heating and cooling across the project is achieved via the use of wall-mounted VRF systems, with the ventilation strategy also allowing the opening of windows for natural ventilation.
The main drivers behind the proposed design were ease of construction, cost efficiency and reusability. The structure needed to be as light as possible to reduce settlements of the shallow foundations in poor quality ground. Timber is the material of choice to enable quick construction, resulting in practical completion in just over a year from the concept design stage. Its low density, in comparison with other traditional construction materials, allowed the use of shallow foundations.
Low rise timber cassette frame construction is well established in the UK. It is a quick and easy form of construction, with shorter leading time, lower material carbon footprint and lower cost. The ability to demount the building and to reuse it multiple times in different configurations was one of the fundamental design drivers. Merging the concept aspiration and the fabrication requirements, a system was developed with the manufacturer and a booklet on how to disassemble and reassemble the building was included in the O&M manual. Timber is also a key feature on the skin of the buildings, with colourful hand painted wooden shingles giving the scheme its vibrant look.
All aspects of design were assessed against circular economy principles, with reuse at the forefront and recycling as the latter of the options. The area is a vibrant hub for start-ups, residents, and passers-by alike, and it has already become a destination for a primarily residential area that is lacking a retail area with identity.
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