As the average price for a detached home in outer London reaches £1m, are these family favourites becoming an endangered species? Today, detached houses account for less than five per cent of the capital’s housing stock – a fifth less than twenty years ago. However, popular South-West London areas Richmond, Twickenham and Chiswick remain a hotspot for these rare, keenly sought after homes and as disparity increases between the price of a detached family house in inner and outer London, there remains plenty of house price growth in these leafy suburbs.