Hammersmith & Fulham Council has approved the demolition of two residential towers because of concerns about their structural safety.
The Hartopp and Lannoy Points, identical 14-storey towers, were constructed between 1968 and 1970 using the large panel system (LPS).
The council’s engineers said that while the buildings have performed satisfactorily over their 45 years of use, there remain “serious structural defects giving rise to significant health and safety issues” with the LPS.
The engineers concluded that the buildings “were not designed to accommodate damage and prevent disproportionate collapse in the event of an accidental explosion. The construction is therefore non-compliant with the requirements for Class 2B buildings.”
In 1968, an LPS was judged to be a factor in the partial collapse of the 22-storey Ronan Point tower in Newham, London. An accidental gas explosion within the tower blew out load-bearing walls causing the fatal collapse of a corner of the structure.
Ronan point collapse closeup
Source: By Derek Voller
Following the Ronan Point disaster, Hartopp and Lannoy Points had their gas supplies removed and additional bracing was added.
Reviewing the coucil’s findings, Arup structural engineers recommended the Hartopp and Lannoy Point towers undergo further reinforcement or demolition as soon as practical.
With renovation of the towers estimated at £16M and demolition priced at £14.1M, Hammersmith & Fulham Council has elected to remove the structures, with 18 of 19 resident responses to the demolition proposal in favour.
Concern about fire safety in the towers was also expressed following the Grenfell fire. As a result, the council changed the buildings evacuation plans and providing 24-hour fire wardens. Fire risk assessments also uncovered “serious issues of compartmentation” within the building.
Engineers involved in the assessments recommended the towers be removed or renovated before December 2020.
In 2018 a report commissioned by Leicester City Council into a similar tower, Goscote House, reported that the tower, which was built using an LPS was currently in good condition. But it said the long-term structural integrity of its concrete frame could not be guaranteed for more than five years.
Two LPS towers in Tottenham are also set to be demolished, after similar faults were discovered last year. Other councils including, Lewisham, Portsmouth, and Rugby councils have all recently demolished LPS residential buildings.
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