Fire rated cladding is external wall material classified for its reaction to fire under BS EN 13501-1, and in practice that means one of two ratings: Euroclass A1 or Euroclass A2-s1,d0. If you are specifying the external wall of a residential block whose topmost storey sits 18m or higher, those are the only two classifications the Building Regulations accept in England. Everything else is detail, but the detail is where projects come unstuck at Gateway 2, at handover, or years later during a valuation.
This guide sets out what the classifications mean, where the legal thresholds sit, and what to ask a supplier for before you write a product into a specification.
What Fire Rated Cladding Means Under UK Building Regulations
The phrase gets used loosely, which is part of the problem. A cladding board is not fire rated because a brochure says so. It is fire rated because a notified body has tested it and issued a classification report against a recognised standard. Two things get confused constantly, so it is worth separating them.
Reaction to Fire Is Not the Same as Fire Resistance
Reaction to fire measures how much a material contributes to a fire once it has started: whether it ignites, how much heat it releases, how much smoke it gives off, and whether it drops burning particles. This is what the Euroclass system measures and what governs external wall materials. Our guide to what an A1 fire rating means covers the top classification in more depth.
Fire resistance is a different question. It measures how long a wall, floor or door holds back fire, in minutes. A compartment wall might be rated at 60 minutes, and that figure tells you nothing about the reaction to fire of the panel fixed to the outside of it.
When someone asks for fire rated cladding, they nearly always mean reaction to fire.
The Euroclass System Explained
BS EN 13501-1 places construction products into seven classes based on their reaction to fire, running from A1 down to F.
A1 sits at the top. An A1 product makes no contribution to a developing fire: it will not ignite and releases no meaningful heat. Steel, concrete, stone and untreated aluminium typically sit here. A2 means limited combustibility, a small organic content that does not accelerate fire spread in any practical sense. B through to F cover progressively more combustible products, with F meaning no performance determined.
Reading the Suffixes: s1, s2, s3 and d0, d1, d2
The letter on its own is only half the classification. Classes A2 down to E carry two additional ratings.
The s rating covers smoke production, applying to classes A2 through D. An s1 rating means little or no smoke, s2 moderate levels, s3 the highest. Smoke is what kills people during evacuation, so this is not a technicality.
The d rating covers flaming droplets, applying to classes A2 through E. A d0 rating means none during the test period, d1 allows droplets that do not persist beyond ten seconds, d2 allows sustained ones.
This is why the regulations specify A2-s1,d0 rather than simply A2. A panel rated A2-s3,d2 is technically Class A2, but it does not comply. Always read the full string.
Euroclass A1 Versus A2-s1,d0: The Practical Difference
For regulatory purposes in England, A1 and A2-s1,d0 are treated as equivalent. Either satisfies Regulation 7(2). Neither is a compromise.
The distinction is commercial rather than legal. A1 products contain effectively no organic material, which limits the coatings and finishes available. A2-s1,d0 allows a small organic content, opening up coating systems and colour ranges that would be impossible at A1 while still delivering non-combustible performance.
Some clients and insurers ask for A1 as a blanket policy. Check whether that is written into the employer’s requirements or simply assumed, because it can narrow your palette for no regulatory benefit. Our comparison of the difference between A1 and A2 fire ratings goes further on this.
Where the 18m Ban Applies and What Sits Below It
The Building (Amendment) Regulations 2018 came into force that December and banned combustible materials from the external walls and specified attachments of relevant buildings in England once the topmost storey reaches 18m. The prohibition sits at Regulation 7(2). Relevant buildings take in dwellings, institutions and rooms for residential purposes, which pulls in blocks of flats, student accommodation, care homes, sheltered housing and hospitals. A 2022 amendment widened the scope to hotels, hostels and boarding houses.
Above that threshold, external wall materials must be classified A1 or A2-s1,d0, subject to a defined list of exemptions covering membranes, seals, gaskets and certain glazing components. The statutory guidance sits in Approved Document B on GOV.UK, and specifiers should work from the current edition rather than a downloaded copy of unknown vintage.
Height is measured to the floor surface of the top storey, from the lowest external ground level next to the building. That measurement decides whether the ban bites, so confirm it early.
The 11m Recommendation
Approved Document B also recommends the same two classifications for the external walls of residential buildings above 11m. This is guidance rather than a statutory ban, but treating it as optional is unwise. Warranty providers, insurers and lenders increasingly apply 11m as a hard line, and a building that misses it can become difficult to sell or remortgage. Our overview of building regulations for external cladding sets out the wider compliance picture.
The Metal Composite Material Exception
One prohibition applies regardless of height or use. Regulation 7(1A) bans relevant metal composite material, meaning panels with an unmodified polyethylene core of the type used at Grenfell Tower, from any external wall or specified attachment on any building. No height threshold, no residential qualification. It is banned outright.
The Rules Are Still Moving
Approved Document B is under active review. Amendments took effect in March 2025, further changes are scheduled for September 2026, and a consultation responding to the Grenfell Tower Inquiry Phase 2 report ran until June 2026, covering external walls, balconies and the combustibles ban. The Building Safety Regulator consultation materials are worth reviewing for any scheme still on site in 2027.
For higher-risk buildings, broadly those at least 18m or seven storeys with two or more residential units, the gateway regime applies. The build up approved at Gateway 2 is the build up that must be constructed. Swapping a product on site over a lead time problem is no longer an option, which makes early supplier engagement more valuable than it once was.
Beyond the Panel: Why the Whole Build Up Matters
A compliant panel fixed into a non-compliant wall does not give you a compliant wall. The regulations apply to materials in the external wall, not just the visible face, so the carrier system, support rails, insulation, cavity barriers, breather membrane and fixings all need checking. A rainscreen cladding system creates a drained and ventilated cavity behind the outer skin, and that cavity needs correct fire stopping to prevent it acting as a flue.
Membranes are a common blind spot. They are generally exempt, but exemption does not mean any membrane will do. Vulcan supplies Fireshield where enhanced fire performance is required, alongside Wraptite, and we manufacture aluminium ZED section for 25mm and 40mm cavities so the support system matches the panel specification.
A Specification Checklist for Fire Rated Cladding
Before a product goes into a specification, work through the following.
- Request the full classification report to BS EN 13501-1 from a notified body, not a marketing datasheet
- Check it covers the product in its end use condition, including coating and backing
- Read the entire classification string including the s and d suffixes
- Confirm the Declaration of Performance and UKCA or CE marking
- Check it covers the exact thickness, colour and finish you intend to use, because coatings affect performance
- Confirm it applies to the system as installed, not the panel in isolation
If a supplier cannot produce a classification report on request, that answers the question for you.
How Vulcan Systems Supports Fire Rated Specifications
Vulcan Systems has supplied cladding to UK projects for over 30 years, working with architects and main contractors from early design through to delivery. We are a supply only business, so our technical team focuses on getting the specification right rather than chasing installation programmes.
The Vulcan Screen Bar System was developed in response to changing fire requirements on public and private housing. It is A2 fire rated, built from secretly fixed aluminium extrusions, and designed both for replacing condemned cladding on high-rise buildings and for new developments needing a non-combustible facade.
VulcaLap aluminium cladding offers tongue and groove or shiplap profiles up to 6.2m, giving the look of timber boarding without the combustibility or the maintenance. Where impact resistance matters, VulcaTuf GRP cladding panels comply with BS 5544 and BS 6206 in any colour, size and thickness.
We also supply Naturetech composite cladding for projects below the regulatory thresholds. Being an engineered timber product it does not carry an A1 or A2 classification, and we will tell you so directly. Matching the right product to the right building is the whole point.
Stock is held in Croydon with UK-wide delivery, backed by a free estimating service and free samples on next day delivery.
Frequently Asked Questions About Fire Rated Cladding
What is the difference between A1 and A2 fire rated cladding?
A1 materials are non-combustible and make no contribution to fire. A2 materials have limited combustibility, a small organic content that does not meaningfully accelerate fire spread. For external walls in England, both A1 and A2-s1,d0 satisfy Regulation 7(2) and are treated as equivalent.
Is fire rated cladding a legal requirement in the UK?
It is for relevant buildings in England whose topmost storey sits 18m or higher. Regulation 7(2) sets A1 or A2-s1,d0 as the minimum there. Approved Document B recommends the same standard above 11m as guidance. Separately, metal composite panels with an unmodified polyethylene core are banned on any building at any height.
What does A2-s1,d0 actually mean?
A2 indicates limited combustibility, s1 means little or no smoke, and d0 means no flaming droplets during testing. All three parts must be met, so a product rated A2-s2,d1 does not comply.
Does aluminium cladding meet fire regulations?
Solid aluminium generally achieves a high Euroclass rating because the metal is non-combustible. Composite panels depend entirely on the core, which is why polyethylene cored panels were banned. Always request the classification report for the specific product rather than assuming from the material name.
How do I verify a cladding fire rating?
Ask for the classification report to BS EN 13501-1 from a notified body, with the Declaration of Performance. Check it covers the exact product, thickness and finish you intend to specify.
Ready to Specify With Confidence?
Getting fire rated cladding right is a matter of evidence rather than assurance. Our technical team can review your specification, confirm classifications for the products you are considering, and provide take offs and samples before you commit.
Get in touch with Vulcan Systems to discuss your project, request a free estimate, or order samples for next day delivery.