Archetech Issue 30 2017 - Page 78

An array of design techniques and options were reviewed, but to minimise disruption to neighbouring properties, and to ensure the site remained accessible at ground level it became clear that the rarely used ‘top down’ construction method was the most appropriate solution. Contiguous piles were installed very close to the boundary walls in order to form new perimeter basement walls and build from the ground up while the basement was simultaneously being cut. Symmetrys worked with the architect to set the proposed ground level at a height that prevented any undermining of the perimeter walls following the installation of the perimeter pile cap/beams and ground slab. The ground slab was specially designed to accommodate an increased imposed load of construction traffic for when it was in a temporary condition. Symmetrys therefore gave careful consideration to the temporary location of the sacrificial plunge piles and set out their location for the contractor. This is key to successful top down construction, where thought must be given to how the structure behaves in both a temporary and permanent condition. With the temporary piles and the ground slab in place the basement could be cut via a large void in the ground slab, while the superstructure was simultaneously erected from the ground floor level up.  This significantly sped up the construction programme. Careful thought was given to formwork layouts on the underside of the ground floor slabs so quality concrete finishes could be exposed in the completed structure, echoing the design of Maison de Verre. Once the ground floor was cast the basement cut commenced through the perimant double height void and the superstructure was erected at the same time. StructureS echoing maiSon de verre and maximiSing architecturaL SpLendour - Designed in 1932 Maison de Verr e was hailed as a landmark in early modern architecture. A primary reason for this was its displays of exposed framework, industrial and mechanical fixtures under the transparency of its façade. The honesty of building materials and the variable transparency of forms was a key feature. Eglon House reverberates this philosophy through the transparency of its structure which provides the building’s main aesthetic. Symmetrys designed steel columns and concreate soffits to be intentionally exposed both internally and externally clearly displaying the property’s mechanics, while polished concreate slab floors are another notable feature. Now fully complete, Eglon House is already becoming an engineering and architectural landmark in this part of London. The finished product is testament to what innovative engineering solutions can deliver in the face to tough site constraints. www.symmetrys.com The finished product is testament to what innovative engineering solutions can deliver in the face to tough site constraints