A group of four developers of housing for older people has filed a claim for judicial review of Khan’s affordable housing supplementary planning guidance (SPG) document.
The SPG, which was adopted in August, introduces a "fast-track" process for dealing with housing proposals where developers offer at least 35 per cent on-site affordable housing.
The SPG states that, where applicants are meeting a 35 per cent threshold for affordable housing provision alongside an appropriate tenure mix and with no public subsidy, they would receive a fast-track approach with no viability assessment being required by the GLA.
But the group says the document represents a substantive new policy, which should have been subject to an independent examination.
It also says that the SPG should have been subject to a strategic environmental assessment, and that it discriminates against the elderly by making the provision of housing for older people less likely, contrary to equality legislation.
The group comprises developers McCarthy & Stone, Renaissance Retirement, PegasusLife and Churchill Retirement Living.
It argues that the nature of specialist housing for the elderly means that the provision of on-site affordable housing is not feasible, and that such schemes will therefore automatically be excluded from the fast-track process under the SPG.
"As the fastest growing demographic in the capital, it is vitally important that the housing needs of older Londoners are addressed," said a spokesperson on behalf of the group. "The current London Plan calls for 3,900 new units of retirement housing to be built each year in the capital."
"While delivery rates are already well short of this figure, few if any new retirement sites will come forward under the mayor’s new SPG and affordable housing process given the unique viability model of specialist retirement housing. This must be addressed," the spokesperson said.
A spokesperson for the mayor of London said: "The mayor’s new supplementary guidance was consulted on for three months and set out a clear approach that makes the planning system in London clearer, quicker and more consistent."
"City Hall is aware of the proposed claim and will be responding in due course," the spokesperson added.