How to make blocks with Grenfell-style cladding safe: the story of three towers in Plymouth

“Residents would have liked it if we’d have done this in six months. But we knew from the start that the priority has to be doing it right,” explains Mr Clark.

Plymouth City Council clad the Mount Wise towers in 1999, primarily to protect them against the weather – 40 years of roaring south-westerly gales and horizontal rain had taken their toll on the concrete, which was beginning to become porous. The buildings’ insulation also needed improving and there was a desire to give the ageing towers a colourful facelift.

The system the council picked was common: Alucomat ACM cladding panels and Rockwool mineral wool insulation. This is less combustible than the cladding at Grenfell, which had ACM and plastic foam insulation. It’s also in line with the building guidance in force at the time. But thanks to the petrol-like polyethylene, it’s still very dangerous.

PCH, of course, did not know this before Grenfell happened. But six days after the fire, it posted a sample panel to the Building Research Establishment (BRE) for testing. It also checked fire doors and smoke alarms in the towers, and drafted in a local security company to provide waking watch services while it waited for the results.

It conducted its own test, too – it took a piece of the cladding to a local fire station, where a firefighter applied a blowtorch to it. It caught fire, but self-extinguished, giving the association some comfort.

But when BRE’s test results came back, they were clear – the cladding had to be removed. And that is where things got tricky.

“The fabric of the building [would have] let water in. There are gaps you could put your hand through,” explains Sue Shaw, director of homes, neighbourhoods and regeneration at PCH. “So we were in a position where we couldn’t just take the cladding straight off.”

The answer was both simple in design and complex in execution. Scaffolding would have to be erected and covered with weatherproof sheeting. Then the cladding could come off inside it and be replaced with a completely non-combustible system, rendered flush to the wall.

As Ms Shaw explains, this is not a straightforward process: “You can’t have a situation where people can’t see out – you can’t put people in a bag. Most jobs like this don’t get done while [the building is] occupied.”

PCH therefore needed something transparent. And fireproof. And robust enough to withstand Plymouth’s rainstorms.

“You wouldn’t believe how difficult it was to find something. Our consultant [Bailey Partnership] came up with essentially the only material there is,” says Ms Shaw.

This material is triple-stitched debris netting. Before attaching it to the towers, they tested it with a hosepipe to ensure it was water-resistant.

It has worked. Inside, the homes look a little dim – as if it is constantly likely to rain outside – but daylight makes it in and the view is unobstructed. PCH has also provided special ‘daylight’ light bulbs to further help.

“There was never a question that we wouldn’t be able to afford to do it” – John Clark, chief executive, Plymouth Community Homes

Housing officers told Inside Housing that one autistic tenant is relieved he can still count the boats in the harbour every morning. Another tenant is still being visited by the friendly seagull he feeds every day, which he has affectionately named ‘Steven Seagull’.

On top of this, the scaffolding had to be made entirely from steel – for fire safety reasons, not a single timber board was allowed. Procuring all this steel was a lengthy process. For safety reasons, contractor Mi-space had to work from the top of the block down, so it was necessary to have the scaffold entirely in place before it could begin. Workers also had to use completely non-sparking tools. Putting all this in place took time.

“The complexity is 95% of [the delay] in getting off the cladding,” explains Mr Clark. “The bit that’s difficult to get across to the media and the government is that doesn’t mean nothing is happening.”

PCH accelerated a £600,000 programme of sprinkler work planned before Grenfell. That is now complete, with the sprinklers boxed in and visible only as small white discs in residents’ homes. You would miss them entirely if they weren’t pointed out.

Two of the towers have now had the cladding removed but will still need a new insulation system fitted next year

It also filled in decorative gaps in the brickwork in the stairwell that could have provided a route to the cladding panels for fire. The 21 leaseholders in the block were offered cut-price 60-minute fire doors (double the legal minimum) that had previously been installed in tenants’ homes and had been made in PCH’s own factory. They were also protected from the cost of other remedial work.

This is because all of this does cost money. Removing the cladding from the three blocks comes in at £11.8m.

The government stepped in last June with grant to cover the work, but PCH had previously allocated funds in its business plan to do it. It had intended to cancel other work to make space: a project to fit insulation on another block in the city was, for example, halted on the day it was due to begin.

“We don’t have that £11.8m to spend twice, so it would have meant delays to other blocks around the city. There was never a question that we wouldn’t be able to afford to do it,” says Mr Clark.

The remaining works come in at £1.2m, which it has also found space for in its business plan; the largest single cost – the sprinklers – was already planned.

There is also the question of loan security. Mr Clark explains that the clad towers were swapped out of loan portfolios to avoid the issue. But it is the kind of thing that could trigger a loan covenant breach at an association that had more affected towers and fewer alternative properties available to act as security. “Some insurers are taking [the towers] down to zero value – so it would have an impact on your business,” says Mr Clark.

Another tough challenge has been evacuation. The buildings have switched from ‘stay put’ to ‘full evacuation’ in the event of fire. Getting 325 people out of the three towers safely is a challenge: it requires knowledge of those with mobility issues, for example.

PCH has placed details of vulnerable residents in a box at the bottom of each tower block. Residents have been told to leave flats and wait on landings if there is a fire, while fire wardens or firefighters climb the stairs to help them evacuate.

This has been tested for real: a few weeks before Inside Housing’s visit, a chip pan caught alight, triggering a block-wide evacuation; in another incident, someone set off an alarm as an act of anti-social behaviour – and was later prosecuted.

PCH staff estimate it took around 30 minutes to clear the blocks in these instances, although some residents did refuse to leave. The CCTV of the operation has been sent to the government’s building safety experts to study.