The project will substantially redevelopa 3,955m site which historically formed the estate of a large house in Fitzjohns Avenue, delivering a three-storey partial rebuild and a new five-storey, angular housing block.The scheme is less than half a mile from the practices Hampstead Mansion block, designed specifically for older residents and featuring an unusual honeycomb floorplan, which won the AJ Architecture Award for the Health and Wellbeing category in 2023.The latest development includes major alterations to an existing three-storey, 1930s red brick extension, which will be converted and extended from one house to four, while the new housing block will be built at the rear on land opposite Maresfield Gardens.AdvertisementSergison Bates said its new housing block has been designed around mature trees, which led to its unusual massing, roughly divided into two halves that are hinged at their central junction. Source:Sergison Bates (taken from planning documents)The project will deliver 4,676m residential floorspace across 33 homesfor developer and site-owner West Hampstead Projects, plus four affordable houses off-site, secured via a Section 106 legal agreement.Camden Councils planning committee voted narrowly to approve the scheme last week (23 January), with five councillors in favour and three against, following a lengthy debate over its lack of any on-site affordable housing provision.At least five local households had also objected on the grounds of affordable housing provision, alongside fears of overdevelopment on the site. Source:Camden Council planning committee documentsIn a report to committee, Camden Council planning officers stated that, while council policy demands a target of 50 per cent affordable housing for developments of 25 or more homes, the policy makes clear that this figure depends on the viability of the scheme.AdvertisementOfficers concluded that, in this case, the scheme is clearly in deficit and cannot contribute to affordable housing, adding: The applicant has demonstrated that it is not financially viable.Recommending the Sergison Bates-designed scheme for approval, Camdens planning officers praised its high-quality design [which aims to] integrate itself into the verdant green setting, concluding that the housing would make positive use of an underused residential building and back garden site, and provide much-needed homes in a highly sustainable location. Source:Sergison Bates (taken from planning documents)Approved: Sergison Bates' proposal for a residential development in CamdenAs well as the 1930s extension, which is currently connected awkwardly to the main house, the site includes fragments of functions, from a derelict asphalt tennis court to various neglected and overgrown gardens, according to a design and access statement (D&A).Alterations to the existing building will include adding a third floor via an inset mansard roof, adding an additional storey to its northern bay, and replacing sash windows to transform the building from a single-family home into four large, six-bed family homes, including two townhouses and two maisonettes.The existing link to the main house will be removed, thereby enabling the gap between the two buildings and the views of the roofscape against the sky to be restored.Meanwhile, the new housing block will be embedded into the landscape, Sergison Bates explained, with a footprint 'shaped by the mature trees in the north, west and south of the site, as well as the main house to the east.The architects explained: To address both conditions the building mass is roughly divided into two halves that are hinged at their central junction.As per the Section 106 agreement, West Hampstead Projects will provide four off-site affordable homes, comprising two-bed houses for social rent, on another site that it owns in Liddell Road, West Hampstead.The Sergison Bates scheme is a development of an earlier planning permission from 2018, which included refurbishing and adding one storey and a rear extension to the existing 1930s building.It forms around two thirds of a wider site incorporating a landscape-led masterplan in Fitzjohns Avenue, the rest of which is to be dealt with via a separate application.