The permitted development plans will see 166 flats put into 22-storey Apollo House and 419 flats into 20-storey Lunar House. The 1970 office blocks stand next to each other on Wellesley Road, straddling Sydenham Road.As far as it is aware, the practice believes the project will be the countrys largest office-to-resi permitted development scheme to date, exceeding Formation Architects 404-home Delta Point build-to-rent scheme, also in Croydon.Lunar House and Apollo House were commissioned by Harry Hyams, best known as the developer of Centre Point, their names reflecting his fascination with space travel in the wake of the 1969 moon landing.AdvertisementThe tower had been used as the headquarters for UK Visas and Immigration. However, the Home Office division has now relocated and Singaporean developer Ho Bee Land is bringing forward the housing plans.Croydon Council has approved two prior notifications for the scheme, meaning it does not oppose the permitted development based on the limited criteria it is allowed to assess, such as fire safety, contamination and transport impacts. Source:Studio Egret WestAxonometric view of permitted development plansStudio Egret West said its scheme re-imagines the future of these iconic, space-age-inspired structures [], ensuring their sensitive reuse while laying the foundation for an innovative and holistic regeneration of the site.The practice said it would preserve the architectural character of the buildings through carefully aligned partitions and window mullions, while gallery access spaces will enjoy natural daylight and panoramic views.The flats will be of various sizes, including family homes, with 75 per cent exceeding national minimum space standards. The flats will also have adaptable layouts, with sliding partitions.AdvertisementThe towers lend themselves to retrofit, according to the architect, as they were originally built as speculative offices with highly adaptable floor plates, featuring a structural grid free of loadbearing walls, continuous ribbon windows and a freestanding lift core.Studio Egret West said the permitted development plans marked the first milestone in a broader vision, with possible later phases including a lunar-inspired landscape, extensions to the existing buildings and a 40-storey lunar rocket tower.View of Lunar House (left) and Apollo House (right)