In 1968, a gas explosion in an 18th-floor flat at Ronan Point in east London led to the building’s partial collapse and the death of four people.
The tower block had been built using the ‘large panel system’ (LPS), whereby prefabricated concrete walls, floors and ceilings, called ‘panels’, are produced in factories and assembled on site to make a building. This was a popular construction method from the 1950s to the 1970s, and it is estimated that there are more than 500 LPS tower blocks still in existence. Most of these will be in council or housing association ownership.
Following the Ronan Point disaster, national concerns over the risk of partial or full collapse in an explosion, high wind or serious fire led to a programme of strengthening LPS blocks.
However, when Ronan Point was demolished in the 1980s, evidence emerged that the original construction and the strengthening work had not been carried out properly.
In addition to these structural issues, some LPS buildings have been found to have gaps between floor and wall panels, which means fire is unlikely to be contained in the flat of origin, undermining the building’s fire safety strategy.
Following the 2017 Grenfell Tower disaster, residents raised concerns about the safety of their buildings.
The then Department for Communities and Local Government wrote to councils in 2017, to ensure they were aware of the importance of knowing the structural history of their LPS buildings, and that their condition and continued structural integrity were understood and monitored.
Subsequent investigations have left little doubt that owners cannot rely on previous strengthening work or surveys that are now out of date.
Several local authorities have decanted residents from blocks following structural investigations, highlighting the growing concern about the structure of LPS buildings.
The LGA has now produced case studies showing how local authorities have investigated issues with their LPS blocks. These show how assumptions about the state of the buildings and the quality of construction need to be challenged through inspections, engagement with external experts, and collaborative working with local fire and rescue services.
They also emphasise the importance of engaging effectively with tenants through an open and transparent approach.
Under the Building Safety Act 2022, all residential buildings more than 18 metres high require a safety case to be submitted to the new Building Safety Regulator (BSR) by April 2024. A key part of this plan will be an understanding of any structural issues a building may have, including whether or not it is LPS.
The LGA is advising its members, including local authorities with arms-length management organisations, to check whether any of their buildings are LPS blocks and, if they are, to ensure that appropriate safety checks are carried out – and not to rely on historic surveys in assessing their safety.
For buildings more than 18 metres high, this will need to be part of the safety case required by the BSR, but the checks should also be carried out on buildings with four to six storeys.
We are sharing this information with other social landlords and urge members to proactively share relevant historical records with current owners where the stock has been transferred.
Visit www.local.gov.uk/case-studies for the LGA’s case studies on investigating the safety of large panel system buildings.