Ronan Point was a 22-storey tower block in Canning Town in Newham, East London, that partially collapsed on 16 May 1968, only two months after it opened. A gas explosion blew out some load-bearing walls, causing the collapse of one entire corner of the building; four people died and 17 were injured. The nature of the failure (caused by both poor design and poor construction) led to a loss of public confidence in high-rise residential buildings, and major changes in British building regulations resulted.
Construction Ronan Point was part of the wave of tower blocks built in the 1960s as cheap, affordable prefabricated housing for inhabitants of West Ham and other areas of London. The building was named after Deputy Mayor Harry Ronan, former chairman of London Borough of Newham's Housing Committee. The tower was built by Taylor Woodrow Anglian using the large panel system building technology, which involves casting large concrete sections off-site and bolting them together to construct the building. The precast system used was the Danish Larsen & Nielsen system. Construction started in 1966 and was completed on 11 March 1968.
Collapse At approximately 5:45 am on 16 May 1968, resident Ivy Hodge went into her kitchen in flat 90, a corner flat on the 18th floor of the building, and lit a match to light the gas stove for a cup of tea. The match sparked a gas explosion that blew out the load-bearing flank wall, which had been supporting the four flats above. The flank wall fell away, leaving the floors above Hodge's living room and bedroom unsupported, causing their collapse. Falling floor slabs from Hodge's floor and the floors above stacked onto the floors below, causing a progressive collapse of all of the floors of the living room portions of the south-east units of the building. The building had just opened, and three of the four flats immediately above Hodge's were unoccupied. Four of the 260 residents died immediately and seventeen were injured and taken to hospital, of whom three were detained including a young mother who was stranded on a narrow ledge when the rest of her living room disappeared. Hodge survived, having been knocked unconscious in her kitchen by the blast. Leaking gas had collected in the hallway outside her kitchen, and the largest area of overpressure from the gas explosion's blast wave occurred at this concentration of gas in the hallway, causing the highest pressures of the blast wave to travel outward to the exterior flank wall uninterrupted. The existing overpressure in the kitchen as a result of the gas explosion's origin there blunted the higher overpressure caused by the hallway explosion, leaving the walls of the kitchen intact and sparing Hodge's life. Hodge's stove had also remained intact, and was taken to her new address. The gas leak was determined to have been caused by a cracked nut connecting the building's gas line to Hodge's stove, which was believed to have cracked due to being overtightened at the time of installation. The force of the blast also had lifted upward a portion of the ceiling in Hodge's unit (i.e., the unit above's floor slab) causing loss of the gravity load between the floor slab and flank wall necessary to keep the flank wall anchored to the floor slab. Further, a subsequent investigation determined that mechanical elements of the floor slab/flank wall connection were not properly designed to account for the effects of gravity load changes due to lateral forces such as high winds or explosions. In the immediate aftermath of the collapse, the managing director of Taylor Woodrow Anglian denied that the collapse was related to a failure of the building itself. The four tenants who died were Thomas and Pauline Murrell, who lived in flat 110, above flat 90 on the 22nd floor (the highest level), and Thomas McClusky and Edith Bridgestook who lived in flat 85, directly below it on the 17th floor. The Murrells had refused their allocated flat eight times, ultimately agreeing to live there only because their former home had been condemned. The low death toll is thought to be due to the early hour of the collapse, when most residents were in their bedrooms, rather than in their living-rooms that were affected by the collapse. The day after the collapse saw three residents dead, three unrecovered, and three hospitalised. The three tenants detained in hospital were Ivy Hodge, in whose flat the explosion occurred and who was suffering from minor shock and burns, Brenda Maughun, who was suffering from a dislocated shoulder, a broken tibia and three broken teeth, and Ann Carter. Ann Carter died in hospital two weeks later, although her death was not directly related to the accident.
Griffiths inquiry
In the immediate aftermath of the collapse, the government commissioned an inquiry, led by Hugh Griffiths, QC. It reported on dangers caused by pressure on the walls from explosion, wind, or fire, finding that although the design had complied with the current regulations, the following recommendations should be implemented:
Gas supplies should be disconnected from existing tall buildings until they have been strengthened Consideration should be given to a requirement to notify the gas board of new gas installations Consideration should be given to improving ventilation in high blocks The regulations for the storage of explosive materials in high blocks should be reviewed All blocks over six storeys should be appraised by a structural engineer Where necessary high blocks should be strengthened Designers of new tall blocks should design them so they are not susceptible to progressive collapse Designers should have regard to recent research on frequency and duration of high wind speeds etc. Designers should have regard to the effects of fire on the structural behaviour of the building
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