Earl of Lytton

A description of the methodology for the revised estimate as of January 2025 can be found in the technical note that accompanies the monthly data release. It can be found here: Building Safety Technical Note June 2025

The revised estimates are based on the recently released Ordnance Survey National Geographic Database data which was not available when the original estimates were calculated. The key assumptions section of the Technical Note refers to the use of Ordnance Survey unique building identifiers in the higher building ranges and this was a key driver for the increase in the range of uncertainty.

There are an estimated 858,000 – 1,298,000 dwellings in mid-rise (11-18m) residential buildings in England.

There are an estimated 858,000 – 1,298,000 dwellings in mid-rise (11-18m) residential buildings in England.

Combustible materials in and on the external walls of new residential buildings higher than 18 metres were banned in 2018.

The Building Regulations 2010 set functional requirements for fire safety, including the need for internal linings and structural elements to inhibit fire spread and maintain stability.

More broadly, in 2021, the Government appointed the Office for Product Safety and Standards (OPSS) as the National Regulator for Construction Products (NRCP) to regulate construction products placed on the UK market. The NRCP and local authorities have powers to enforce the law where products do not comply with the Construction Products Regulations 2013. The regulator has prohibited the supply of construction products including certain insulation, toughened glass, and plywood. Following the Grenfell Tower Inquiry's report, the Government has committed to bringing forward reforms to ensure that all construction products supplied in the UK are safe.

Part 4 of the Building Safety Act 2022 requires that building safety risks in Higher Risk Buildings are assessed, managed and controlled. The assessment must be suitable and sufficient and all reasonable steps must be taken to manage and control the building safety risks.

The Act does not set out specific standards that should be used. However, standards and guidance relevant to other regulatory regimes such as the Regulatory Reform (Fire Safety) Order 2005 and BS 9792:2025 Fire Risk Assessment. Housing. Code of Practice will be relevant. Assessors can also refer to the published criteria used by the Building Safety Regulator for Building Assessment Certificate applications.

The assessment of ‘life critical fire safety defects’ does not form part of the Act. It is instead a feature of the Developers’ Remediation Contract and the Responsible Actors Scheme, which encompass a wider range of buildings.