ÿþThe envelope of a building is part of the topography of the street, the street part of the landscape of the city. Negotiating the contours between them is a vital part of good inner city architecture. Urban Salon's social housing scheme, Bermondsey Island, provides a case study of the variety of ways this can be done successfully; including material and opacity variations, landscape detailing, colour differences and changes in use. Located at the intersection of Tower Bridge Road, Long Lane and Abbey Street the building lies directly over the site of a scheduled ancient monument and was formally the home of Bermondsey Abbey; the archeological value of the site causing yet another reason for the careful consideration of how the building meets the street. Before the technical challenges began however, it was the ideas of local residents that helped get this project, literally, off the ground. Urban Salon won the competition in 2003 with a diagram that demonstrated they could maximise the development potential thanks to their understanding of both the site and wider neighbourhood. Consultation with the locals in the adjacent pub brought with it the call for a local bingo hall and combined with a conviction to raise the living accommodation clear of the pavement, the submission proposed to lift the flats above the street and then manipulate the form to respond to the different environment on each side of the block. Two of the four sides responded to the busy junction with a heavyweight, closed facade, allowing the remaining faces to display a more open, lightweight appearance. The finished building remains faithful, in form and strategy, to that original competition sketch. There are ???? flats, supporting storage/plant space and a commercial unit totalling ???? square metres. The first four storeys rise up in the same form as the site, maximising the footprint, with the top two storeys and solar panel covered roof stepped back to prevent too much overshadowing to the surrounding streets. A natural solution to the heavyweight facade might have been brick. However with the building hard up against the pavement the prospect of long term maintenance to pointing over public areas resulted in the use of a product that removed this altogether. Ibstock's 'Tilebrick' is a clay product available in traditional blue and red tones and is designed to mimic the appearance of traditional tile hanging whilst being laid as a solid brick. A richness of texture and shadow can be better achieved, along with an interesting association to a well understood domestic vernacular, without the dangers from wind or impact damage inherent in a standard tile hung detail. Relying on this richness, the planning department were presented with a scheme proposing that the two facades nearest the busy Tower Bridge Road were clad entirely in Tilebrick, and the opposite faces rendered in white. The submission was one of the early cases to be commented on by the newly formed design review panel at Southwark Council. Urban Salon's director Alex Mowat recalls the decision to allow the Tilebrick to meet the ground caused some concern and the initial recommendation was that the base should be entirely glazed, but support from one of the panel members helped persuade the rest of the committee to approve the design as proposed. Another important factor in ensuring the project remained as drawn from planning to tender and construction was the decision to complete drawing packages for stages E & F before awarding the Design & Build contract. A schedule of specials and cut bricks for each of the different angled corners was prepared as part of the tender information. With Urban Salon novated by the developer Igloo over to the winning contractor Allenbuild SE, the continuity of the design team was undoubtedly a key part of the successful delivery of the envelope as originally envisaged. As a social housing scheme supported by funding from the HCA, the design also had to meet the necessary criteria of the HQI system, Lifetime Homes and Code for Sustainable Homes. The project achieves Code Level 4, assisted in part by the extensive photovoltaic solar panel array on the roof which was required not only for the emissions improvement over building regulations, but also Southwark's demand for 20% carbon savings as a planning condition. Delivering enough surface area to meet this proved challenging and the architects explored various configurations before ultimately settling for a single horizontal plane with each panel mounted on stands to achieve the optimum pitch. The maintenance access areas of the roof, as well as the balcony decks serving the apartments, were covered in Ecodeck; a recycled plastic alternative to timber. The reduction in movement and warping in comparison to a traditional timber product was welcomed by the site manager. A reduction in maintenance should also benefit Hexagon Housing Association. As the original competition sketch had predicted, the envelope's role in protecting the inhabitants from the noise of the city played a part in all aspects of the detailing and product choices. With the goal of meeting the latest WHO sound reduction standards, the support of an acoustic design consultant was necessary to closely examine the combinations of materials and fixings. Although the front and rear of the building displays two very different surface finishes - one shielded by masonry, the other rendered white like it's interior and thus conveying openness - the difference is only visual and psychological, as the same level of sound reduction had to be achieved throughout. This required alternative details that took into account acoustic issues such as avoiding resonance (and with it the danger of amplification) across insulation products of matching depth within the cavity or lightweight steel cladding that supported the Tilebrick and render. Sound reduction detailing and materials are only ever as good as the holes you make in them however, thus ensuring that the ventilation strategy was also impacted by proximity of the noisy traffic. Choosing background ventilation with extract meant the need for a number of outlets, each requiring an acoustic baffle and careful siting. In places they could be concealed in soffits or within the window frame, but in others the rendered surface had to be broken. Both the visual and technical impact of the individual extract system suggests this was perhaps a good candidate for a centralised solution that could have also capitalised on heat recovery. The composite windows (top hung due to the weight of the glazed unit used to achieve the sound reduction) were provided by Krone in grey and white for the two differently coloured sides of the building. So how successfully does the building's envelope meet the city's landscape? In the full height glazed entrance facing Abbey Street the residents collect their mail in the pavement slab covered foyer before entering the private stair in the centre of the plan; protected from the pavement by the reassuringly tough brick core. To the south the building opens its ground floor again with the glazed commercial facade looking across at the site of the now demolished pub where once the call for bingo had set this project on it's way. Building envelopes that meet the street entirely with glazing in an attempt to create continuous landscape surfaces can too often result in only a forest of reflections and wayfinding confusion. Bermondsey Island proves that the way to avoid this is to choose your moments. The masonry cladding helps this building to firmly inhabit the site, the careful planning of uses provides the necessary commodity and the finished surface is a delight.