More than 1 in 10 (11%) new affordable homes to rent and buy in England can no longer be built due to the costs of making buildings safe following the Grenfell Tower fire, according to new research by the National Housing Federation (NHF).

Housing associations surveyed said homes for social rent will be the worst affected.

The survey, which spoke to 106 housing associations, found that 61 have discovered dangerous materials on their buildings since the fire, despite having been signed off as meeting building requirements at the time they were built.

Without additional funding for safety work, these not-for-profit organisations are having to cut plans to build 12,900 new affordable homes over the next five years, in order to prioritise spending on building safety.

They had been planning on building 116,777 affordable homes over this time. Housing associations built 25% of all new homes in England last year, and this includes the vast majority of new affordable homes.

Mounting building safety costs are also affecting housing associations’ ability to invest in the upkeep of the homes they already own, where social housing residents live.

Those surveyed said they are having to divert £730m away from routine maintenance work, such as upgrading bathrooms or kitchens, to pay for essential building safety work.

In response to the current building safety crisis, housing associations estimate they will have to spend in excess of £10bn to make all their buildings safe over the next decade.

As not-for-profit organisations, they are having to divert this money – which is largely from the rents of their social housing residents – away from investment in existing social homes and building new affordable housing.

By comparison, profit-making private developers and cladding manufacturers, who constructed these unsafe buildings and produced unsafe and flammable materials, say they are setting aside only £643m from their profits to cover building safety costs.

In February, the government made £3.5bn of additional funding available for homeowners to remove dangerous non-ACM cladding from high-rise buildings. However, there is no funding to remove this cladding from buildings where social housing residents live, or for other safety works beyond cladding.

The National Housing Federation is calling on the government to fund the upfront costs of all fire safety works on behalf of social housing residents and leaseholders and claim this money back from those responsible such as private developers and manufacturers, once works are completed.

Kate Henderson, Chief Executive of the National Housing Federation, says: “This research shows that the costs of making buildings safe will be borne by the poorest people in our society for many years to come.

“Not-for-profit housing associations are putting their residents’ safety first, but without funding they are left with no choice but to divert money away from building new social housing for those most in need. It is simply not right that people who are at no fault and on the lowest incomes in this country are left to shoulder these costs.

“Those responsible for this crisis, developers of unsafe homes and manufacturers of dangerous materials, must be made to pay. In the meantime, we urge the government to do the right thing, and fully fund the upfront costs of making buildings safe.”