Metal composite material
On 1 June 2022, the government introduced a ban on the use of metal composite material (MCM) panels with unmodified polyethylene (PE) core on all new buildings at any height. This is the type of cladding that was used on Grenfell Tower.
Research published by the Department in April 2020 demonstrated that this type of MCM PE poses such a significant fire risk that an outright ban on its use on any buildings, regardless of height or purpose, is justified.
The cladding used on Grenfell Tower was actually aluminium composite material (ACM) with an unmodified polyethylene core (ACM PE, or ACM category 3). MCM PE includes any metal, alloy or metal compound.
Metal composite materials are defined in approved document B of the building regulations as: '...any panel or sheet, having a thickness of no more than 10mm which is composed of a number of layers two or more of which are made of metal, alloy or metal compound and one or more of which is a substantial layer made of a material having a gross calorific value of more than 35MJ/kg when tested in accordance with BS EN ISO 1716. A substantial layer is defined as a layer which is at least 1mm thick or has a mass per unit area of at least 1kg/m².'
For more information see: Metal composite material panel systems MCM and MCP and ACM cladding.
[edit] Related articles on Designing Buildings
Featured articles and news
Apprenticeships and the responsibility we share
Perspectives from the CIOB President as National Apprentice Week comes to a close.
The first line of defence against rain, wind and snow.
Building Safety recap January, 2026
What we missed at the end of last year, and at the start of this...
National Apprenticeship Week 2026, 9-15 Feb
Shining a light on the positive impacts for businesses, their apprentices and the wider economy alike.
Applications and benefits of acoustic flooring
From commercial to retail.
From solid to sprung and ribbed to raised.
Strengthening industry collaboration in Hong Kong
Hong Kong Institute of Construction and The Chartered Institute of Building sign Memorandum of Understanding.
A detailed description from the experts at Cornish Lime.
IHBC planning for growth with corporate plan development
Grow with the Institute by volunteering and CP25 consultation.
Connecting ambition and action for designers and specifiers.
Electrical skills gap deepens as apprenticeship starts fall despite surging demand says ECA.
Built environment bodies deepen joint action on EDI
B.E.Inclusive initiative agree next phase of joint equity, diversity and inclusion (EDI) action plan.
Recognising culture as key to sustainable economic growth
Creative UK Provocation paper: Culture as Growth Infrastructure.
Futurebuild and UK Construction Week London Unite
Creating the UK’s Built Environment Super Event and over 25 other key partnerships.
Welsh and Scottish 2026 elections
Manifestos for the built environment for upcoming same May day elections.
Advancing BIM education with a competency framework
“We don’t need people who can just draw in 3D. We need people who can think in data.”