Landscape, History and Time
The Layered Gallery replaces the three storey closet wing of an 18th Century Grade II Georgian town house in Bloomsbury, London, to provide storage and display of art, a toilet, an outdoor kitchen and areas to sit in the sun and look onto the garden.
Working with our Landscape architect, Todd Longstaffe-Gowan, we approached the design as a garden building that works with the historical techniques of pattern and layering that were originally devised due to the height of Georgian houses and how small their gardens were- they were gardens to look at from above.
Structure, Geometry and Pattern
The entire tree like façade of the gallery is supported by a weathering steel frame made from flat stiffened plates branching out over the three‐storey structure and supported off just two 120 x 12mm steel posts with a stiffening rib on the rear face. Unusually however, and in a reversal of the usual structural hierarchy, the façade is also the main structural frame of the gallery and supports all the floors and roof, as well as providing stability.
From a layer of plants that we hope will eventually cover the building, to the structure and layer of glazing and framing, to blinds, sliding racks to store art, a secret toilet, and finally the original brick garden wall, the layers deal not only with history and materials, but also the relationship to nature and light, display and privacy.
Materiality and Craft
We like to work with one material and make it work really hard on every project we do. Here weathering steel was chosen due to its structural and self-maintaining ability, and was used not only for all structural and external elements, but also for most of the internal furniture and fittings.
Smallness, Transformation and Brief
We overlapped opposing programmes of a toilet with storage for art, and sunbathing with viewing art. We made the room as narrow as the swing of the window, made column free space to create an atmosphere of lightness, and borrowed a sense of space from the courtyard.
Construction finished just over three years ago but the careful integration into the existing and the growth of the garden’s vegetation already make it difficult to tell how long the extension has been there.
Gianni Botsford, Gianni Botsford Architects
Description of structure and materials
The gallery building is fabricated from weathering steel, an alloy of steel that forms a stable oxide surface unlike typical steel from which the rust flakes off.
The entire dendritic façade of the gallery is supported by the weathering steel frame made from flat stiffened plates branching out over the three-storey structure and supported off just two 120mm x 12mm steel posts with a stiffening rib on the rear face. Unusually however, and in a reversal of the usual structural hierarchy, the façade is also the main structural frame of the gallery and supports all the floors and roof, as well as providing stability.
The 25 or so steel members in the façade are made up of a family of just three sizes; 120mm, 100mm and 70mm – all fabricated from flat plate and selected for each member subject to the load path and the forces that the member is subject to. The numerous connections (45+) were carefully coordinated and detailed to conceal the bolts.
Because the façade is the structural frame and therefore outside the building envelope, the floor beams that connect to the façade are detailed with a thermal break in them at the glazing line. In effect the main floor beam stops at the glazing line and is supported off weathering steel plates cantilevered from the façade members.
Material Used :
1. CorTen structure: Thresher Fabrications
2. Cor Ten Glazing, sliding screens: Palladio SpA, Treviso, Italy
3. Bespoke Cor Ten WC cabinet: Dolce Steel Novo, Padova, Italy
4. Blinds: Silent Gliss, Cameron Bloom
5. Internal and External Flooring: Lazenby
6. Light fittings: Floor and wall lights, Hunza, Ceiling lights, Modular
7. External Kitchen: Roshults
8. Fold away WC - Lagares