Category: Featured

ACM – where are we going with this now?

The Grenfell fire was an absolute tragedy and highlights the need for an urgent review of building regulations and design standards which is now underway by the DCLG (Department of Communities and Local Government). Their objective is “to make sure residents of high rise buildings are safe, and feel safe, from the risks of fire”. The criteria to not just “Be Safe” but also to “Feel Safe” almost certainly means that the revised building regulations will leave no grey area and while the focus is on ACM (Aluminium composite material) the use of class C products the industry have relied on like PIR or PUR insulation will be challenged too. Systems like render that use class E EPS (expanded polystyrene) as a backing insulation are very much at risk of being banned.

The approach to “holistic design” for fire strategies has got to change and if this prevents another Grenfell then this will be good news. Certainly as a cladding contractor we have found the advice of ‘Fire Consultants’ at times to be unclear and questionable. Many contractors are now only considering construction techniques that incorporate non combustible class A1 materials such as mineral wool so that they are safe in the future from litigation while new standards emerge. Being caught short using a product which may suddenly appear on the deleterious materials list part way through the contract is just not a risk worth taking.

What though for projects that have recently been completed or refurbishment works? Aside from ensuring that there is strong and effective fire compartmentation and safe escape routes,  changing the cladding on the outside of an existing building is not a straight forward decision making process. There is a risk that replacing an ACM material now and leaving behind a PIR or PUR insulation results in the need to repeat the activity to change these too in the future. The problem is that to change from a PIR to a mineral wool requires a 66% larger insulation zone which is space that may not be available. If you are working on a significantly older building too then the old insulation was probably also thinner than todays standards making the depth needed unachievable without major work and possibly planning or boundary implications.

Landlords across the country are currently wrestling with the question if there is a need to replace anything, and if so then how much. It is likely to be another 6 to 10 months before clear guidance on the new building regulations is available. This video footage of the 18-storey Mermoz tower fire in Roubaix, France shows the staggering speed that fire can spread in an ACM cladding material for anyone who has any doubt that they need to replace this product if it is in use.