Owners of flats in buildings without cladding will no longer need an EWS1 form to sell or re-mortgage their property, following a new agreement reached between the government and the Royal Institution of Chartered Surveyors (RICS).

Regulations introduced to improve fire safety following the Grenfell fire had inadvertently left flat owners trapped in near-unsellable homes.

After the Grenfell tragedy in June 2017, the rules implemented meant that mortgages for flats in buildings over 18m tall would only be approved if they had passed an External Wall Fire Review (EWS1) survey.

However, the government and RICS have agreed that buildings without cladding do not need an EWS1 form, clearing the way for up to nearly 450,000 flat owners to sell, move or remortgage their homes.

But mortgage lenders said they “did not consent” to the announcement of the changes, after it was initially claimed by the government that UK Finance and the Building Societies Association (BSA) had also approved the new agreement.

While building owners are already legally required to undertake fire risk assessments on all blocks of flats, following supplementary guidance published by the government, RICS will be working with lenders, valuers and fire safety bodies to develop new advice for surveyors. This will enable surveyors to take a more proportionate approach and reduce the number of buildings where an EWS1 assessment is needed.

This training will be delivered by RICS from January and will mean up to 200 additional assessors will be qualified to carry out the EWS1 assessment within a month, 900 within three months, and 2,000 within six months.

The government is also exploring ways to address ongoing concerns around the availability of professional indemnity insurance and welcomes industry’s progress on developing a portal where lenders, valuers and leaseholders will be able to find out if their building already has an existing EWS1, thereby reducing the demand for duplicate forms.

The housing secretary Robert Jenrick said: “Through no fault of their own, some flat-owners have been unable to sell or re-mortgage their homes - and this cannot be allowed to continue.

“That’s why the government has secured agreement that the EWS1 form will not be needed on buildings where there is no cladding; providing certainty for the almost 450,000 homeowners who may have felt stuck in limbo. However, this is only part of a wider solution and we continue to support those homeowners who do have cladding on their buildings and where there is still more to do.

“I welcome the support we have received from RICS and industry to resolve this matter and will be working urgently with lenders to resolve these challenges, ensuring that EWS1 forms are requested only where absolutely necessary and that the number of surveyors able to complete them is increased urgently to meet demand.

RICS CEO Sean Tompkins commented: “We are aware of the severe impact this has had on some homeowners and we agree that buildings without cladding should not be subject to the process. We will be taking forward work with industry on this.

“Further, we recognise the acute market shortage of fire engineers to carry out EWS1 assessments and welcome the Government’s support on working with us to upskill other regulated professions, such as Chartered Building Surveyors, to create additional capacity in the market.”

Reflecting on the government’s announcement about EWS1 forms, Mark Hayward, chief executive of NAEA Propertymark, said: “The requirement for an External Walls Systems 1 (EWS1) form has delayed or caused sales to fall through, as flat owners have had to depend on their freeholder to commission the work and so few buildings have the form already.

“It’s great to see lenders, the industry and government come together to take a far more proportionate approach to the need for an EWS1, ensuring that those living in buildings with no cladding will not require a form to sell or remortgage their property. Owners however will need certainty as to whether their building has any cladding so that they don’t get caught out during the process.”