Gas supplies were cut off at four London tower blocks late Thursday after structural engineers found the buildings did not comply with safety recommendations introduced after the 1968 Ronan Point disaster.
Tower blocks at the Ledbury Towers estate in south London, which contain 242 flats between them, had been undergoing investigations by Arup engineers since 17 July due to reports of cracks appearing across the ceilings, walls and floors.
The investigations were not directly related to those launched after the Grenfell Tower tragedy. There, a newly-installed rising gas main is under investigation as a possible cause of the devastating fire.
At Ledbury, engineers also discovered that strengthening works at Ledbury Towers may never have been carried out despite records which suggested it had.
The estate’s gas supply was installed when the blocks were built between 1968 and 1970, soon after a gas explosion had caused a partial collapse at Ronan Point, a similar tower block in Newham.
After the disaster, regulations were introduced for buildings with piped gas and blocks with a similar design underwent strengthening works. The requirements are detailed in the Building Regulations 20109, while recommendations for compliance are listed in the BRE 2012 best practice guideline (BR 511).
“After carrying out intrusive investigations Arup has informed Southwark Council that the blocks do not comply with the government recommendations for the robustness of large panel system tower blocks with piped gas,” said a spokesperson for Arup.
“It is important to note that Arup’s findings are completely separate to the issues of the cracks, and could not have been discovered without intrusive investigations.”
In a letter to residents Southwark Council explained gas supplies would be turned off because it was “not willing to take any risks” with their safety.
“At every stage of this investigation, we have put residents’ safety first, and acted on the best information available. We didn’t own the blocks when they were constructed at the end of the 1960s, but all the reports we found suggested the blocks were strengthened following the Ronan Point incident in 1968, to make them safe to include a gas supply,” said Southwark Council deputy leader and cabinet member for housing Stephanie Cryan.
“Arup’s structural investigations suggest this strengthening may not have occurred, and we have therefore turned off the gas, until further investigations can be done.”
Residents will be evacuated from the blocks while gas work is carried out, but the council said this will be done in a planned way over a period of days.