Squeezing suburbia

Planning, 28 September 2007

Lower-density suburban family housing is popular but unsustainable. Higher-density flats are more sustainable but tend not to meet families' needs. That is the dilemma being faced by housing providers.

Research now under way suggests that highly cherished suburban qualities can be achieved in higher-density schemes through careful planning, good design and effective management. But care is needed to integrate these schemes into existing suburbs, particularly if the aim is to make neighbourhoods more sustainable.

Architect Sir Richard MacCormac is developing planning and design guidelines for family housing. Meanwhile, a recent report published by research group Design for Homes (see panel) urges planners to introduce standards for open and communal space in high-density developments and require management plans.

One cap on the increasing density of new housing schemes could be English Partnerships' proposals to introduce minimum space standards for developments on its sites. This would avoid the very small flats that currently attract speculators. A benchmark of approximately 51m2 is being considered for one-bedroom flats and 77m2 for two-bedroom properties.

MacCormac has secured funding from English Partnerships to assemble a team of planners and landscape specialists to take forward housing models with densities of up to 120 dwellings per hectare (dpha) while still retaining suburban qualities. The team, which includes planning consultancy Colin Buchanan and landscape designers Macfarlane Wilder, aims to develop a tool kit for planners, developers and local authorities to improve the quality of new homes.

Range of suburban densities established

The practice is hoping to apply the results on a major site in the Thames Gateway. MacCormac's interim report on "sustainable suburbia" establishes a range of densities in which many of the benefits of higher-density living can be achieved without sacrificing home buyers' aspirations for their own house and garden and their own front door in safe, quiet and leafy streets.

MacCormac maintains that high-density homes do not necessarily have to feel cramped as long as they include open spaces, low height to space ratios, low artificial light levels, low traffic levels and private gardens. He points to some still thriving early suburbs built to densities of more than 50dpha.

The report sets out a variety of indicative layouts demonstrating how three-bedroom family homes can be arranged to achieve densities of between 57dpha and 87dpha. Groups of eight houses around a courtyard achieve lower density, while mews housing that eliminates open parking areas by incorporating spaces underneath three-storey properties builds up the overall density.

The major challenge is the provision of access roads. Engineers typically require a highway hierarchy with a spine road and roundabouts that determines the housing layout. MacCormac's director of housing Duncan McKinnon argues that roads and housing need to be designed together. The partnership's designs are based on traditional streets on a grid pattern.

The urban place supplement to the Essex Design Guide goes further, suggesting that some roads should be seen as extensions of the homes that they serve. The supplement, now being adopted by several Essex authorities, is intended to guide developments of more than 50dpha. It emphasises that public and semi-public space becomes even more important given the limited private space in high-density schemes.

Essex Design Initiative urban designer Peter Dawson talks up the concept of "play streets", in which roads can be used as a playground for children. Play streets keep vehicle speeds low by physical means such as alignment, public art, play equipment, cycle stands, bollards, trees and planters. The supplement stresses that "poorly designed areas of grass to the rear of blocks of flats will no longer be an acceptable way of providing communal gardens".

Fitting high-density development into existing suburbs poses major challenges for transport provision, site availability and architectural integrity. Hildebrand Frey of the University of Glasgow is part of the Cityform research group that examines sustainable urban forms. He is investigating approaches to increasing densities in neighbourhoods to the group's target of a minimum level of 60dpha.

Academic studies local area sustainability

Frey is developing a method to analyse and increase neighbourhoods' sustainability. A case study of Govan in Glasgow reveals limitations on the availability of development land. "It may be that councils need to be proactive and demolish lower-density homes, replacing them with higher densities, if they want to create sustainable neighbourhoods," he says.

John Pounder, associate director for planning at Colin Buchanan, is keen to ensure that suburban quality is not affected when high-density developments are being considered. Pounder was part of a team commissioned by the South East England Regional Assembly to develop policies to introduce character appraisals as part of the planning process for suburban renewal.

"The policy agenda is only now catching up with the reality that many high-density housing schemes are affecting traditional suburbs," he says. Development has to fit into existing public transport frameworks, he insists. "Higher-density development should not go ahead if there is inadequate existing public transport and no potential for its provision," he contends.

Many developments are being proposed on the edge of existing suburbs that lack good public transport connections, Pounder warns. These schemes need to be considered in the wider context of transport availability, he maintains. In his view, the areas with the greatest potential for higher-density development are large low-density housing estates.

The nation's suburbs are set for radical changes to accommodate major housing developments. The challenge is to expand their offer while ensuring that they continue to meet the needs of their traditional residents and at the same time become more sustainable.

SUBURBAN STRATEGY

The South East England Regional Assembly broke new ground in putting forward policies for suburbs in its draft regional spatial strategy (RSS). These could be strengthened following last month's panel report.

The panel (Planning, 31 August, p1) supports the inclusion of policies on suburbs in the RSS and wants the government to develop guidance. Its report says suburbs will be "key areas of change and there is a recognised national policy deficit on this topic".

The South East Plan calls for a planned approach to increasing density, promoting character appraisals and area action plans. The panel says policies should identify clearer objectives for intensification.

These might include strengthening local services, promoting public transport and diversifying uses on underused sites. Without such measures, it warns, there is a risk that "intensification will remain an ad hoc response through the planning system".

SUPER DENSITY SUCCESS

Planning professionals need to apply a range of stiff criteria for layout and management plans if high-density housing is to work for families, argues Design for Homes chief executive David Birkbeck. This summer the research body published a pamphlet by a group of high-profile architects calling for more guidance on the design and management of high-density housing.

Birkbeck points to the ever-increasing density levels now being approved in London, which sometimes exceed those achieved in Hong Kong. In Whitechapel, a scheme equivalent to 1,600 dwellings per hectare (dpha) is currently being considered by the London Borough of Tower Hamlets.

The architects, who include Levitt Bernstein, PrP and HTA, have produced the pamphlet in response to panic that such schemes will turn into the slums of the 21st century. While accepting that high densities are needed to house the growing population, the authors urge planners to scrutinise applications not just for their aesthetic qualities but also how they fit into their context, given the direct impact on quality of life for families living at very high densities.

Developers are resorting to flats at 80dpha and some urban housing types can realise up to 120dpha, the report notes. It recommends much greater use of maisonettes with private gardens and ground-floor front doors. Blocks comprising maisonettes back to back, each with a front door, double the available floor space for ground-floor family accommodation, it finds.

The document also emphasises the need for all homes to have access to private open space in the form of balconies or communal gardens. "Balconies should be large enough for six people to have a barbecue," says Birkbeck, who suggests that sizeable roof terraces could present another option.

He urges local authorities to develop space standards similar to those in Dublin, where there is a fixed requirement for schemes to comprise a proportion of private open space. He also observes that Georgian-style gardens could be created in the centre of housing developments to provide communal space for surrounding high-density housing.

There is a growing recognition that management is needed for high-density housing developments, not least for common parts. Design for Homes maintains that management arrangements should be considered as part of planning applications. The pressure on shared spaces means that extensive management needs to be considered from the outset, it argues.

"Historically management has been under-funded," it comments. "Steps must be taken at the inception of super density developments to ensure that adequately funded and well ordered management will be provided." It suggests that compliance should be achieved by developers entering into legally binding agreements, preferably with the local authority at the planning stage.

Recommendations for Living at Superdensity is available at PlanningResource.co.uk/doc.