Southwark Council has sought to reassure residents that the safety of its new rooftop extensions are its ‘highest priority’, despite early reports highlighting the risk of ‘disproportionate collapse’ and the extent of ‘invasive and costly’ work required.
This month, Southampton Way Estate Tenants’ and Residents’ Association wrote an open letter to councillor Stephanie Cryan, who holds the new homes portfolio at Tooley Street, urging her to reconsider the council’s proposals to build two extra storeys across the Peckham estate. The group described the current plans as potentially ‘fatally flawed’.
The letter, organised by chair Nick Flower, states: “Residents on Southampton Way Estate are justifiably very worried and concerned the council is proposing to go ahead and build on blocks which its own feasibility study recommended against.
“Doing so without presenting any indication that extensive structural surveys have been done to justify a decision which goes against its own expert opinion… And in doing so have set themselves on course to construct a fatally flawed rooftop development which risks the lives of a great number of residents.”
In October 2019 we first reported on the council’s plans to build new homes on flat roofs on existing estates as one of many ‘creative’ ways to solve the borough’s housing crisis, similar to controversial ‘infill’ developments where new housing is shoehorned into green spaces, disused buildings, or built on top of demolished garages. Around 28 estates had been identified as potential sites.
The council believes 32 new social rent homes could be added onto Southampton Way via a rooftop development, with the council saying this could be far cheaper than buying land or real estate on the open market.
The first report to look at the scheme in any detail was a general study into the feasibility and cost, completed by ARUP, after being commissioned by the council in August 2020. This report raised doubts that buildings could cope with added wind pressure when gaining extra storeys, and also highlighted the risk of disproportionate collapse in blocks that predate the 1970s. The surveyors noted, for example, that adding just a single extra storey on top of a four-storey building would increase wind loading forces by 50 per cent. It concluded that building just two extra storeys on a four flight block would be “‘relatively unlikely to be possible due to the very significant increase in wind loading.”
It also claimed: “Disproportionate collapse regulations were only introduced in 1970, therefore pre-1970s buildings will not have been designed for disproportionate collapse and most are unlikely to meet the requirements.”
Not only would proving the work was safe require “intrusive internal surveys” it would also be ‘very costly’ – though details on exactly how costly are limited.
The most horrific example of disproportionate collapse in a high rise was seen in Newham’s Ronan Point tower block in 1968, when a gas explosion caused one side of the entire building to disintegrate, killing four people and injuring seventeen.
Major changes to national building regulations were subsequently implemented to ensure that in the event of a similar structural issue or event – such as a fire – damage is contained within a particular floor or area, and the entire building does not collapse like a house of cards.
A further report, from December 2020, looks at more detail on ten estates earmarked for rooftop homes across Southwark, including Southampton Way, nine of which are assumed to have been built before the 1970s. This report references ARUP’s findings and recommends that only single storey extensions are added, along with strengthening works – except for in the case of Southampton Way which, against the council’s recommendations, is earmarked for two new floors.
There is also confusion over the exact age of the estate. The council’s report fails to confirm the construction date, but one longstanding resident who has lived there since 1970 has told the TRA he believes it was constructed eight years earlier.
The majority of the council’s post-war housing stock was taken over by the local authority years after being constructed, and in some cases with key information missing. Initially many blocks were built and maintained by the Greater London Council which was dissolved in 1986 with its powers handed over to the London boroughs. In some cases, buildings had been commissioned by the previous body, London County Council, which was disbanded in 1965.
Record-keeping failures meant that Southwark Council was unaware strengthening work listed as having taken place on Ledbury Estate’s towers in the aftermath of Ronan Point had, in fact, never taken place. Invasive structural surveys eventually revealed the truth and – due to the high cost of work needed – the blocks are being demolished rather than refurbished.
Given the case of the Ledbury, and the ongoing fire safety issues continuing to emerge in tower blocks across the borough, it is not surprising that residents are concerned that surveyors and the council do not have accurate information about the the buildings for which they are developing complex proposals.
Safety is only one issue. Although the council has pledged not to carry out any extensions without cast-iron guarantees that they can be done safely, residents are rightly asking whether the process is worth it – worth the cost and worth the stress for residents whose homes will be under hugely disruptive building sites.
A letter from Cllr Cryan to Southampton Way TRA, shared with the News last Thursday, has explained her position.
She described the initial feasibility study as a ‘ very general, desktop based, study’ that makes ‘some blanket comments about some of our older blocks currently being unsuitable for extensions – but the report also goes on to suggest it is possible with some additional works.”
Cllr Cryan highlighted that any potential site would have ‘in-depth assessments’ and be judged on a ‘case by case basis’, adding: “Please be assured that no works would take place where there was any doubt to the safety of our residents or the structural integrity of the building.
“The council is also aware of the impact extensions will have on people living in the affected buildings and has drafted a series of principles and commitments to maximise the benefits and minimise the impact on residents, and we will continue to consult and engage with residents as our proposals move forward.”
She also confirmed that “further comprehensive investigative works and surveys will be carried out to determine the structural stability of the blocks and their exact load capacity,” before adding: “Our residents’ health and safety is our highest priority and we will not proceed with the development until the structural works have been concluded and we are satisfied with the findings.”