New regulations banning combustible cladding on high-rise residential construction in the United Kingdom will still allow builders to use combustible materials in external facades if they begin foundation work on a construction site before the last week of February 2019. This would include the later phases of a multi-tower project.

“It is the commencement of work on the first of the buildings within the application which determines whether all the building work can take advantage of the transitional provisions, not each individual building,” a guidance document from the UK’s Ministry of Housing, Communities and Local Government states.

As announced in the UK parliament in late November, a prohibition on combustible materials in the external walls of buildings will go into effect for new construction of multi-storey dwellings at least 18 metres (60 feet) in height as of December 21, 2018. However, the combustible cladding ban will not apply if building approvals are in place prior to that date and any of the following activities are underway by February 21, 2019:

• excavation for strip or trench foundations or for pad footings;
• digging out and preparation of ground for raft foundations;
• vibrofloatation (stone columns) piling, boring for piles or pile driving; or
• drainage work specific to the building or buildings concerned.

The new rules — following the deaths of 72 residents of London’s Grenfall Tower in June 2017, attributed to the rapid spread of flames via the 24-storey building’s aluminum composite material (ACM) cladding — now require cladding materials to meet a minimum fire safety rating of European Class A2-s1, d0, meaning that they are non-combustible, and produce little or no smoke and no flaming droplets or particles during the first 10 minutes of exposure to fire. This covers: most residential occupancies, excluding hotels and rooms in hostels or boarding houses; hospitals; long-term care homes; boarding school dormitories and other student accommodations that are at least 18 metres in height.

At the same time, the UK government is pushing local housing authorities to get moving on the removal and replacement of existing ACM cladding. This includes an offer of “financial assistance, if necessary”, although it is mandated that costs are to be recovered from building owners.

“Everyone has a right to feel safe in their homes and I have repeatedly made clear that building owners and developers must replace dangerous ACM cladding, and the costs must not be passed on to leaseholders,” asserts the UK’s Secretary of State for Communities, James Brokenshire. “My message is clear. Private building owners must pay for this work now or they should expect to pay more later.”