INCA Case Study: Cluny Mews, Earls Court London

The first element to point out in this application is that every material on the façade of this residential building is part of the Alsecco external wall insulation system – clay brick slips on the main wall areas, long format clay slips on the window inset panels, cut stone slips to make up the spandrels running between floors and green glazed ceramic brick slips on the ground floor and interspersed within the buff bricks.

Alsecco have worked with the developer of this scheme in Manchester previously so when they were looking to develop a block of high-end residential apartments in London with very challenging construction issues, Alsecco were approached to advise on the capabilities of their EWI systems onto a steel-frame construction. This early input by Alsecco into the design process proved invaluable so the design was a collaboration between the developer, architect, steel frame manufacturer, Alsecco and SFS/EWI installer.

The particular challenges of the site were numerous but included a very tight footprint in which to work, the site being squeezed between a railway line and goods yard, existing residential properties, an office building and large electronic advertising boards on the A4. This necessitated a wall build-up which made maximum use of insulation and removing unhelpful masonry mass and cavity layers, the ability to create offsite panels for a large elevation where access was severely restricted, as well as reducing vehicle movements and storage. In addition, tight planning conditions required the façade to be aesthetically stunning to attract high-end buyers.

​Preliminary meetings with Alsecco determined that the main wall areas lent themselves to the Ecomin 400 system with purpose-made brick slips. However, quite early in the design process it became clear that significant cost and construction benefits could be derived from using the same construction method for all areas of the building such as the floor slab spandrels, window insets adjoining the balconies and the complex ground entrance areas to each apartment. The system was also able to be constructed offsite for the ‘hard to reach’ areas and traditionally on-site application for the remainder of the scheme, with exactly the same system employed. Steps in the façade could also be easily achieved through varying the insulation thickness as required. Alsecco’s ability and experience in providing different specialist mortars for clay, ceramic and stone made up the full system specification for the project and a demonstration sample panel was constructed on site for planning approval.

Alsecco worked with their supplying partners to source the main 15mm clay slips, the long format clay slips, the architectural stone blocks which were cut into slips on two sizes by specialist cutters, and the high-quality glazed green ceramic brick slips – four separate suppliers were used but the backing system was consistent throughout; the Alsecco Ecomin 400 system incorporating high density mineral wool insulation with Alsecco’s specialist basecoat, bonding and pointing mortars.

Construction began with the offsite panels constructed in Manchester for the large side elevation to the building, and then when EWI installation began on site once the offsite panels had been positioned, the main wall areas were installed. As the scheme backed up to the main A-road, the thinner wall build-up meant that more internal living space was created than would have been the case had the building been constructed using traditional masonry construction. Likewise, the complex ground floor design with sloping soffits and angled columns would have been much more difficult and expensive to create if built traditionally. Alsecco made regular site visits to support the installer, INCA member CWS, and even during inclement winter weather conditions, the façade could be deemed weathertight as soon as the basecoat render had been applied.

The finished building is superb in providing an aesthetically high-class frontage to these new apartments in one of London’s most prestigious postcode areas. The quality of materials and seamless way in which they combine demonstrate the versatility of external wall insulation as a modern construction method and how the Alsecco system overcame the practical challenges to the scheme without adding complexity to the construction process.