CF Møller is rethinking the use of engineered timber for its scheme to replace Robin Hood Gardens following the government’s ban on combustible cladding materials for tall buildings
The practice was appointed in 2017 for the redevelopment of the eastern side of the the east London housing estate designed by Alison and Peter Smithson in the 1960s.
Early designs for the 330-home scheme, half of which will be affordable, have been designed in outline using cross-laminated timber (CLT) construction.
But housing association Swan has confirmed it is now rethinking the use of CLT on the regeneration of the Poplar estate, now called Blackwall Reach, as a direct result of the government’s ban on combustibles.
The new legislation, which came into effect last December, prohibits all materials with a European fire rating of less than A1 or A2 in the external wall construction on residential blocks, schools, care homes and hospitals above 18m in height.
Geoff Pearce, Swan’s executive director of regeneration, said that for the buildings above this threshold – a height of about six storeys – it was now considering alternative materials, with a hybrid structure one of the options.
He said: ‘We’re in the very early stages of considering it [Blackwall Reach] as a CLT modular building and that will now need to be rethought.’
Asked about the wider implications of the ban, Pearce said: ’We think it’s unfortunate, as we believe that CLT performs really well under fire load and it got caught by a ban that wasn’t specifically targeting CLT as a material.’
CF Møller’s scheme is the latest phase in a wider phased regeneration masterplanned by Metropolitan Workshop, which will replace the estate’s former 250 homes with 1,575 new units.
A spokesperson for Swan, which is developing the site in partnership with the GLA and the London Borough of Tower Hamlets, said: ’Phase 3 has been outline-designed in CLT. However, as a result of the combustible materials ban, Swan will be developing the designs with architects CF Møller, looking at different ways of constructing schemes above 18m.
’There are a number of options being explored that continue the use of CLT for the main internal structure and these options will be completed over the normal course of the design process.
’The design stage of Phase 3 may take longer than expected but this will not affect the overall programme and there will be no delays in terms of start on site or completion.’
Swan, which has pioneered the production of modular homes, has set up its own factory in Essex where it is producing schemes such as Waugh Thistleton Architects’ mid-rise housing scheme Watts Grove in Tower Hamlets.
Following the ban, the government faced criticism from CLT specialists, which had called for the method to be exempt from the regulation change. At the time, Waugh Thistleton accused the government of ‘overreaching its aims’.
Ministers first announced in June that they intended to stop combustibles being used following pressure from campaigners including Grenfell United, a group representing survivors and bereaved families of those who died in the fire in 2017.
On Blackwall Reach, Phase 1b and Phase 2, which includes 268 new homes in four new buildings designed by Haworth Tompkins and Metropolitan Workshop, are currently on site and due to complete in 2019 and 2021 respectively.
Phase 3 is due to start on site in 2021-2022 once the residents living in the existing building have been rehoused into the completed Phase 2 homes.