Large-scale housing developments have the potential to lower prices, but only if they are planned carefully, report shows.

A study of six large housing developments in the South West region by the Royal Town Planning Institute (RTPI) has found large developments can have a positive affect on affordability.

While the housing developments in the study range from 650 to 8,000 units, the RTPI concludes that any large development of the size envisaged in the Government’s garden village plans play an important part in solving the housing crisis.

The report’s modelling indicates house prices will likely be between 1% and 8% lower in the housing markets by 2021 than they would be if the schemes were not built. By 2031, they are project to be between 2% and 15% lower.

The RTPI also suggested these master-planned developments could also increase the stock of local affordable social housing by up to 50%.

However, the report warned the contribution of these sites were largely produced through strategic planning processes which have now been abolished.

It called for ‘urgent steps’ to be taken to find new ways of bringing forward new large sites.

‘The experience of the last 20 years shows that piecemeal incremental developments alone will not meet the level of demand for new homes,’ said Richard Blyth, the RTPI’s head of policy.

‘We must therefore ensure there is proper, long term planning and delivery for housing on a large scale.

‘However, the Housing White Paper hasn’t really addressed the critical issues facing large sites.

‘It asks whether planning procedures should be streamlined to ‘support innovation and high-quality development in new garden towns and villages’, but our report shows that we need more, not less, planning to getting large sites right without the delays and compromises we see so often.’

David Lowin, chair of the RTPI South West region, said: ‘The advantages of large scale releases of land for housing and the building of communities is clear in this research.

‘However, allocations are not going to be successful or delivered in an efficient way unless those who are dealing with such schemes in planning departments are given the resources.

‘Councils are facing a £5.8bn funding shortfall by 2020, and planning departments are in dire need of additional funding having suffered disproportionately from cuts in the age of austerity since 2010.’