Re/making The Street  

In order to meet London’s housing needs, density must increase unless the city sprawls outwards. Most experts agree increased density can help the city work more sustainably and efficiently, and improve living conditions.

The question is how to densify.

One of the most dense cities in the world, Singapore, scores high on liveability. With the housing complex Pinnacle@Duxton, it boasts the world’s tallest residential complex — a linked set of seven towers rising up to 50 storeys, with sky gardens at the 26th and 50th floor stretching for up to 500 metres. This public development of affordable housing was completed in 2009 and won a clutch of awards as well as being popular to live in.

Singapore has 75 people per hectare while London is on 17 per hectare — but that still puts London sixth in the world for ‘wide area density’ with only Asian cities ahead.

That might suggest London needs to build skyscrapers to come close to meet housing demand. However, this doesn’t follow. More infill and brownfield re-use, with low-to-mid rise housing, can greatly increase density. One way to improve density is to build with greater respect to the street pattern of London. Many postwar estate redevelopments disrupted the most efficient use of space by rupturing the street plan.

Savills’ Completing London’s Streets report, prepared for the Cabinet Office and published in January 2016, calls for an ‘intensification’ of the streetscape, infilling and reintegrating estates within the street pattern.

Higher densities are achieved that may rehouse occupants, ol.,add more homes for sale or rent, and generate increased valuation to the overall asset. In this, the key is to ensure that increased density makes for a better street rather than overcrowding and straining infrastructure.

Central Paris provides one of the most cited examples of a dense mid-rise standard being imposed as a redevelopment. Seven to eight storeys consistently apply, set by the model of Haussmann’s boulevards in the nineteenth century. These great avenues and their ancillary roads were designed to remove the squalid and overcrowded slums in the city centre, where occupants were prone to revolutionary outbreaks. Haussmann’s plan delivered highdensity housing, shops and other services, with grand facades and courtyards behind, but little green space.

The grand boulevards and buildings of central Paris, planned by Baron Haussmann for Emperor Napoleon III in phases from the mid-19th century, did away with cramped slums (and the social unrest they helped foster) but deliver a model for urban densification that finds favour for its human scale. Photo: Jean-Charles Martel/Artedia/VIEW

In the late 1980s a celebrated development designed by Renzo Piano, the housing at Rue de Meaux, picked up on that scale and wove in an innovative and yet respectful housing block, achieving density that respected the street and yet delivered a small communal park.

Much closer to our key study development of Portobello Square in West London lies the highly desirable neighbourhood of Holland Park. The grand Victorian terraces in and around Lansdowne Crescent, with generous private communal gardens, are among the more dense housing in London in terms of dwellings per hectare, three to four times the average of many other areas. This is achieved by long terraces and a deceptive six floors (one partly below ground and one set back in the roof) with generous shared open spaces. Nothing goes to waste in land use while the design quality make for highly desirable homes.

The grand mid-Victorian terraces of streets like Lansdowne Crescent, off Ladbroke Grove, achieve a density of liveable rooms per hectare much greater than most housing in London despite being among the most expensive dwellings. Generous communal gardens and other public realm qualities are major contributors to value. Photo: Maria Lauro Alonso

A report by the Greater London Authority in 2003 summarised three different architectural solutions to achieving 75 dwellings per hectare.

The 2003 GLA report Housing For A Compact City includes a diagram that shows how very different forms of architecture – terraced streets, blocks around communal gardens, or high-rise in open space – can be the same density, in this case 75 dwellings per hectare, but deliver very different private and public qualities of space.

Portobello Square emulates one of those, with its mix of terraced housing blocks and open space. A small park will be overlooked by housing and the neighbouring streets featuring terraces that descend a floor from street level and step back a floor at the top, greatly increasing the building density without breaking the typical street scale. This may be a new approach after the Wornington Green Estate but is one that looks back to the best of the mid-Victorian neighbours and forward to what is likely to become a London standard density.

In the 2015 report Redefining Density, Savills drew attention to the relationship between density and connectivity. It suggests it could guide where we build to fix the housing shortfall, if development targeted the best connected low density areas. If London density was raised to the average for each area in relation to its connectivity, more than 1.4 million homes would be added. This is more than three times the GLA 10-year housebuilding target.