The location of substantial residential and business uses within easy walking distance of an urban or neighbourhood centre is the principal platform for sustainable development. This catchment (at least 5000 homes for a typical, sustainable neighbourhood) can support a bus route and a variety of shops and services and can attract other commercial investment. It requires an average neighbourhood density of around 65 dwellings per hectare with higher density towards the centre of the neighbourhood (or town centre, transport corridor etc.). This allows for lower densities towards the margins of the neighbourhood towards the rural edges.

Many sites suitable for development are located within existing neighbourhoods that incorporate a range of densities – and these may not combine to an average density of 65 dwellings per hectare. Indeed, this is the case for the majority of urban places in Essex.
In contrast, new garden community developments can be easily designed to achieve this density – but applying it universally across a development would not produce the ideal variety of housing stock or an attractively diverse environment. In such situations, where there is the scope to construct a new layout model based upon sustainable urban design principles, density should become a by-product of the process rather than its driving force.

Many emerging development sites require a minimum development density target which is applicable to the different development models suited to the context of the site. The most compact development is required in the most sustainable locations, with a progressively reducing minimum density beyond these locations. There is no upper density limit within these specific areas. By undertaking an appropriate context analysis, designers and Local Authorities will be able to determine the appropriate target density. These decisions need to be informed, in part, by the accessibility of the site, volume of development and the proposed provision and mix of amenities (such as shops, green spaces and schools) that are so vital for higher densities to function. Some of these amenities can be established or improved over time either via the process of new development or through the management of market forces. Nevertheless, within larger developments (of 50 hectares or more) it is essential that these amenities are in place at the beginning of the development of the new community.