Aluminium composite material
Aluminium composite material (ACM) is a flat panel made from two thin aluminium sheets bonded to a non-aluminium core, between three and seven mm thick.
The panels have a painted or metallic finish, for example a copper or zinc effect. ACM cladding is used as panels on the outside of buildings, including residential towers.
ACM cladding is not dangerous but it's important to use the right type.
Identifying ACM cladding
To tell the difference between ACM and a solid aluminium sheet, you need to look at a cut edge where the lamination is visible. If there isn’t a cut edge, you’ll need to cut a hole in a panel.
When testing is necessary
If a building has a floor over 18 metres above ground level and has ACM panels, the owner must make sure the panels meet building regulations guidance.
The owner needs a safety check to confirm the core material in the cladding is a material of limited combustibility (this includes materials of Class A2-s3, d2 or better to meet BS EN 13501-1).
Getting a free safety check on cladding
If you’re responsible for private housing in a tower block with ACM cladding, you can send samples for a safety check.
A landlord, managing agent or owner can take and send sample ACM cladding for testing. If there are several owners or people responsible for the same building, one set of samples is accepted for testing.
It is free to test the sample cladding. The owner would be responsible for any remedial action or safety improvements to the building.
Where to sample cladding on a high rise building
When you or a surveyor is certain the cladding is made from ACM, you need to take two different samples from the same building. It is important to use sample cladding above and below 18 metres from the ground.
Take photographs to help you identify the cladding samples. Where you remove a sample, you need to close the hole using a non-combustible sheet such as steel fixed with self-tapping screws or rivets.
Protocol for sampling of aluminium composite material cladding
At two different locations in a residential building:
- cut two samples about 250x250mm
- on each sample use indelible ink to write the building name, number, postcode, a unique identifier and a direct dial telephone or mobile number
- complete the data return form and give as much information as possible about the building
- put one sample from each location and the data return form in a padded envelope and write “Urgent – cladding test samples” in capital letters on the envelope
Download a data return form to send with your samples of ACM cladding.
Buildings Research Establishment (BRE)
Keep the second sample from each location for your own records or for testing if the first sample is lost or misplaced.
More information about safety checks on ACM cladding
If you want more information about ACM testing, contact:
More useful links
- Fire safety in the home
- Landlord and tenant obligations
- Problems with your landlord - how the council can help