Residential buildings over 18m with ACM cladding on GLA Group estate

The cladding on Grenfell Tower in June 2017 was immediately identified as one of the contributing factors in the rapid fire spread across the outside of the building.

Following a testing programme, the government’s expert panel made the following assessment of the three categories of ACM:

• ACM with a limited combustibility filler (category 1) can be used safely, although this is also dependent on how it is fitted.
• ACM with a fire-retardant filler (category 2) may be used safely with non-combustible insulation and appropriately fitted cavity barriers. The safety of this category is highly dependent on the insulation used, and how it is fitted.
• ACM with an unmodified polyethylene filler (category 3) with any type of insulation presents a significant hazard on buildings over 18m and should be replaced.

The GLA owns the freehold of three sites confirmed with ACM cladding.

• Site 1 had three buildings (a total of 181 homes) with confirmed Category 3 ACM, and a further two buildings (139 homes) with Category 1 ACM. The ACM was installed as part of the original design and construction. The ACM was purely decorative, with a very low coverage of the external walls. The long leaseholder commenced removal of the Category 3 ACM cladding in 2020. Remedial work preparation commenced in July 2020 with removal of the first panels beginning in October 2020. Practical completion was achieved on 1 February 2021. Individual leaseholders were not charged. The head lease for this site started in 1999 for a lease term of 999 years.
• Site 2 comprises three blocks with eight stair cores (a total of 297 homes) with confirmed Category 3 ACM. The ACM was installed as part of the original design and construction. Interim fire safety measures were put in place, including a waking watch, funded by the long-leaseholder. The long-leaseholder agreed to replace the cladding and individual leaseholders were not charged. Remediation work started in April 2019 and has been confirmed now completed by the developer. The head lease for this site started in October 2012 for a lease term of 999 years.
• Site 3 is a single building of 232 homes with confirmed Category 2 ACM. The ACM was installed as part of the original design. The responsible person has agreed to replace those elements of the façade associated with combustible cladding and individual leaseholders will not be charged. Preparation works for replacing the cladding started in 2020 and remediation works are currently targeted to be completed by the end of 2022. The block is in the process of undergoing an elevation by elevation strip in line with the build sequencing in the programme. Interim measures, including fire alarms, heat detectors and waking watch, are being funded by the long-leaseholder and will be in place until completion of the works.