Green spaces threatened by property developers
We need London to be a city that can weather hot summers and heavy downpours. A place that reduces stresses and increases contact with nature. Instead, we have paved over green spaces 22 times the size of Hyde Park. This increases flood risk as rain has nowhere to go. Sewers overflow and the city is hotter. All of this makes the city less liveable.
Property developers are adding to these problems by refusing to build enough affordable housing. This puts councils under pressure to build on the grassy spaces around the old blocks of flats. This is called infill. The Council owns this land. They are also the planning authority. If the infill is for less than 150 homes they don’t have to consult local people. This lack of accountability and the residents’ lack of power means infill schemes are increasingly attractive.
Infill developments mean people will lose the places where they relax and children play. Stress will increase. Privacy will be lost. Local flood risk will increase as will heat islands. Biodiversity will be reduced. Many of these neighbourhoods already have a lower amount of accessible green space, losing the communal gardens on their doorstep will push them into deficit.
In Peckham a developer recently cut the amount of affordable housing from 35% to 12%. From Tottenham to Lewisham, and across London developers regularly refuse to build more than 10% -18% affordable homes. In many cases developers say they can’t afford to build as much affordable housing as Councils want. This was the case in Peckham. In June 2025 the Nation Audit Office published a report looking at developer funding. One of the key issues was how developers use viability assessments to justify how much affordable housing they are willing to build. These are “financial appraisals that establish whether a site is viable by examining whether the value likely to be generated by the development is more than the cost of developing it, including a profit for developers.”
The NAO concluded that “Asymmetries of skills and resources between Local Planning Authorities and larger developers, the complexity of financial viability assessments, and a lack of coordinated support from central government, all need to be addressed…Until they are, we cannot conclude that the current approach represents value for money.”
The NAO found LPAs felt there was an power imbalance “Larger developers have the resources to employ consultants and legal experts to challenge viability, and find any way to negotiate contributions down. There is a lack of skills and capacity within LPAs to address technical and legal viability challenges.” Also “Viability assessments are difficult for LPAs to challenge as they are not transparent, and LPAs do not know if costs included by developers are realistic and reasonable.” There is a lack of developer accountability. With something as crucial to society as housing we can’t allow developers to hold so many of the cards.
We expect developers to be more responsible. We expect them to help meet the United Nations Sustainable Development Goal calling for cities to be made “inclusive, safe, resilient and sustainable.” This requires that there is “universal access to safe, inclusive and accessible green and public spaces, in particular for women and children, older persons and persons with disabilities.”
When developers refuse to build enough affordable housing which see green spaces built on, that breaches the Sustainable Development Goals.
As an example of the problem, the photo above is an estate in Lewisham. The Council wants to build on them both. This would be a significant loss of space. The largest is 0.25 hectares. These green spaces are in the catchment of the River Pool. Rain is absorbed by these areas, reducing the pressure on local sewers and preventing flooding. They are also spaces where people can play and relax. Developers’ private gain shouldn’t come at a public cost.
We need to you press the Government to change the power dynamics by changing viability assessments. We need them to be transparent. We need to know if they are realistic and reasonable.
Email template:
Dear Ministry of Housing, Communities & Local Government,
You say that guidance on viability assessments for developers will be published this year. In June this year the National Audit Office published its report “Improving local areas through developer funding”
It has previously found that the “developer contributions system was complex and not working effectively to maximise the amounts collected, with developers able to negotiate lower contributions on the grounds of financial viability.”
The NAO in June said “assessments are difficult for Local Planning Authorities to challenge, since they do not know if costs included by developers are realistic and reasonable; and larger developers have the resources to employ consultants and legal experts to find ways to negotiate contributions down.” They also say that the MHCLG acknowledges that practice guidance on financial viability is too simplistic.
The NAO found LPAs felt there was an power imbalance “Larger developers have the resources to employ consultants and legal experts to challenge viability, and find any way to negotiate contributions down. There is a lack of skills and capacity within LPAs to address technical and legal viability challenges.” Also “Viability assessments are difficult for LPAs to challenge as they are not transparent, and LPAs do not know if costs included by developers are realistic and reasonable.”
Under the Freedom of Information Act 2000 I would like to request the following information:
1) The NAO recommends that MHCLG “review the perceived conflicts of interest that arise from consultants representing both LPAs and developers with regard to viability assessments, and determine whether any action is needed.” Has MHCLG done this?
2) The NAO also recommends that MHCLC “review viability assessments and how they are used, including evaluating whether removing them would make the system work better, or whether there are other ways of improving outcomes (such as open book costing);” Has MHCLG done this?
Electronic communication is fine,
Yours faithfully,