Specifying A1 Non-Combustible Wall Panels: What EN 13501-1 Actually Means for Your Project

A project brief lands on the desk with a fire compliance clause: wall linings in public areas must be A1. You know gypsum panels are non-combustible. But when the contractor asks for the certificate, and the compliance team asks what A1 actually guarantees after painting — the answer needs to be precise. This post covers what EN 13501-1 Class A1 certifies, what it does not certify, how to verify it on a datasheet, and why the distinction between an inherently non-combustible material and a chemically treated one matters at the specification stage.

Table of Contents

• The Euroclass system — what EN 13501-1 classifies
• Why A1 matters when specifying interior wall panels
• How to verify A1 classification in a specification
• Why gypsum achieves A1 without chemical treatment
• Wall panel materials compared under EN 13501-1
• Specifying A1 3D gypsum panels in practice
• Frequently asked questions

The Euroclass System — What EN 13501-1 Classifies

EN 13501-1 is the European harmonised standard for classifying the reaction to fire of construction products. Developed under the Construction Products Regulation framework and administered by the European Committee for Standardization (CEN), it establishes the Euroclass system — the reference that EU member states use to define and verify fire safety requirements for wall linings, floor coverings, and pipe insulation.

The standard divides construction products into seven main fire classes

For wall linings, two additional sub-classifications apply alongside the main class. The s designation rates smoke production: s1 (little or no smoke), s2 (moderate), s3 (substantial). The d designation rates flaming droplets: d0 (none produced), d1 (limited), d2 (not classified). A product classified simply as A1 carries no s or d sub-notation — at this level, smoke and flaming droplet production are negligible by definition. For a complete breakdown of performance classes and criteria, the Measurlabs EN 13501-1 guide is the most current public reference.

What "non-combustible" means — and what it does not

A1 certifies that the material does not contribute fuel load to a fire. It does not ignite, does not sustain combustion, and does not propagate flame. According to the RISE Research Institutes of Sweden — which contributed to the technical development of the Euroclass system — A1 materials show no heat release and no flame spread under the standard test conditions of EN ISO 1182 (furnace test) and EN ISO 1716 (calorific value test).

One distinction that matters in practice: A1 reaction-to-fire classification is separate from fire resistance. Reaction to fire describes how a material behaves when exposed to flame — what it contributes to the fire. Fire resistance (governed by EN 13501-2) describes how long a wall assembly can contain a fire from one side. A specifier working on a hotel project typically needs to satisfy both: A1 for the wall lining material, and a fire-resistance rating for the partition structure. They are different certifications and different tests.

Why A1 Matters When Specifying Interior Wall Panels

When A1 is required

National building regulations across the EU reference EN 13501-1 to set minimum fire class requirements for interior wall linings. A1 or A2 is typically required in:

• Hotel corridors, lobbies, stairwells, and public gathering areas
• Healthcare facilities — patient corridors, operating areas, communal spaces
• High-rise residential buildings (height thresholds vary by jurisdiction, commonly buildings above 11 m)
• Publicly accessible retail, restaurant, and commercial spaces

The exact threshold depends on the national building code of the project country, not on EN 13501-1 itself. The standard defines what each class means. National regulations define when a given class is required. Verify fire class requirements with the local fire authority or a qualified fire engineer at design stage.

The CPR framework and CE marking

The Construction Products Regulation (CPR, EU No 305/2011) requires manufacturers to issue a Declaration of Performance (DoP) for construction products bearing CE marking. For wall panels, the DoP must state the fire classification against EN 13501-1. This is not optional marketing material — it is the legal document that a contractor, building inspector, or compliance team will request on site.

Kandes is a Swiss brand producing A1 non-combustible gypsum wall panels manufactured in the European Union. Our 3D gypsum wall panels are CE marked. The Declaration of Performance states A1 non-combustible classification under EN 13501-1. That document is available on request from the specification team.

How to Verify A1 Classification in a Specification

Reading the Declaration of Performance

The DoP is structured around the harmonised standard under which the product is certified. For wall linings, that standard is EN 13501-1. The document will state:

1. The product name and type description
2. The intended use (interior wall lining)
3. The fire class — given in Euroclass notation, for example A1
4. The notified body number — a four-digit identifier for the third-party organisation that issued the classification

If the fire class reads A1 with no additional notation, the product is fully non-combustible. A classification of A2-s1,d0 is a different — and lower — classification. Some suppliers use descriptions that blur this distinction. They should not be treated as equivalent.

What to request from your supplier

For any wall panel specified in a fire-sensitive application, request these four documents:

1. CE Declaration of Performance with EN 13501-1 A1 classification explicitly stated — not referenced, stated
2. Test report reference or third-party certificate number — the evidence behind the DoP
3. Written confirmation that the classification applies to the panel as supplied — unpainted gypsum panels, since the paint system applied on-site is outside the scope of the panel's DoP
4. Technical installation datasheet — substrate requirements, adhesive system, and any installation conditions that could affect the classification in use

Why Gypsum Achieves A1 Without Chemical Treatment

The chemistry of non-combustibility

Gypsum is calcium sulphate dihydrate — CaSO₄·2H₂O. It is a mineral. When exposed to heat, it releases chemically bound water through an endothermic process. That reaction absorbs heat rather than contributing it. There is no organic compound to ignite. No carbon chain to sustain combustion.

Per Eurogypsum, the European gypsum industry association, this thermal behaviour is why gypsum has been used in fire-resistant construction for well over a century. The Gypsum Association's technical guidance confirms the same endothermic mechanism as the basis for gypsum's fire performance in construction assemblies. As a Swiss producer of architectural wall panels manufactured in the EU, Kandes builds on this well-documented material science. Our gypsum wall panels are composed of natural gypsum. No synthetic binders are present in the finished panel — the organic binder used during production dissolves in the manufacturing process. The A1 classification follows from the composition of the material. It is not an engineering workaround.

Treated vs. inherently non-combustible — the specification distinction

Some wall panel categories achieve A2 or B classifications through chemical fire-retardant treatments applied during or after manufacturing. Some fire-retardant treatments may degrade over time or prove incompatible with certain paint systems — a factor worth confirming with the supplier for projects with long design lives.

A mineral gypsum panel carries no such dependency. Non-combustibility is the mineral itself. For projects with a 10-year or longer design life — hotels, healthcare buildings, high-spec residential — this is the relevant distinction. The classification does not degrade because the material composition does not change.

Wall Panel Materials Compared Under EN 13501-1

The table below is a reference for the specification stage. Classifications shown are typical for each material category. Always verify the specific product's DoP — individual products within a category can vary.

The practical consequence: when a specification requires A1 interior wall linings, the working options are mineral-based — gypsum, ceramic, stone, fibre cement at A2, and certain composite systems with a verified A1 core. Decorative panels in PU foam or PVC fall outside A1 compliance and outside most commercial and hospitality specifications where fire safety is a condition.

Specifying A1 3D Gypsum Panels in Practice

Specification language

For a project requiring A1 wall linings, the following clause covers Kandes 3D gypsum panels accurately:

3D architectural gypsum wall panels, A1 non-combustible (EN 13501-1), mineral composition, no synthetic binders in the finished panel, continuous seamless pattern, installed unfinished and painted on-site in the specified colour.

This reflects what the product is and what the Declaration of Performance covers. It does not extend beyond the panel as supplied.

Points to confirm before approving a sample

Classification scope. The DoP covers the panel as supplied — unpainted gypsum. Confirm this with the manufacturer.

Paint system. Painting with a water-based or mineral paint does not introduce a combustible layer and will typically preserve the non-combustible performance of the panel. Solvent-based paints add an organic layer that may affect the system sub-classification. For hospitality and public-space projects, specify a water-based paint system.

Substrate compatibility. Kandes gypsum wall panels install onto plasterboard, concrete, rendered plaster, and primed substrates. Substrate preparation requirements are covered in the installation manual. Confirm the proposed substrate system before finalising the specification.

Seamless pattern. The continuous pattern is achieved through correct grouting and surface finishing — a property of the installation process, not of the fire classification. Ensure the installation contractor is familiar with the material before the first project.

CAD files and panel documentation for specification workflows are available for download. The full technical specification dossier — Declaration of Performance, fire certificate, density datasheet, and installation guidance — is available on request from the specification team.

Frequently Asked Questions

What does A1 fire rating mean for wall panels?

A1 is the highest classification under EN 13501-1 — the European standard for reaction to fire. A wall panel rated A1 is non-combustible: it contributes no fuel to a fire, produces no significant smoke, and generates no flaming droplets. Gypsum achieves this through mineral composition. Calcium sulphate dihydrate does not burn; it releases water when heated. The classification is a consequence of the material, not a treatment applied to it.

Is A1 fire rating required for hotel interiors?

In most EU jurisdictions, hotels and public accommodation must use wall linings classified at minimum A1 or A2 under EN 13501-1 in corridors, lobbies, and public areas. The precise threshold depends on the national building code and the building's height and occupancy. Verify the specific requirement with the local fire safety authority or a qualified fire engineer during the design stage — EN 13501-1 defines the classification, but national regulations define when each class is required.

What is the difference between A1 and A2 fire rating?

Both are within the non-combustible or near-non-combustible range, but they are not the same. A1 certifies zero contribution to fire development. A2 permits a limited combustibility level, accompanied by mandatory sub-classifications for smoke (s) and flaming droplets (d) — for example, A2-s1,d0. For interior wall linings in hotels, hospitals, or high-rise residential buildings, A1 is the preferred specification and, in many jurisdictions, the required one.

How do I verify a wall panel's fire rating?

Request the manufacturer's Declaration of Performance (DoP). Required under EU Construction Products Regulation 305/2011, the DoP states the fire classification against EN 13501-1 and includes the notified body reference that issued the classification. That is the legally valid document for compliance verification. Marketing datasheets and product descriptions are not sufficient on their own.

Does painting a gypsum panel affect its A1 fire rating?

The A1 classification applies to the panel as supplied — unpainted. Water-based and mineral paint systems do not introduce a combustible layer and typically preserve the non-combustible character of the assembly. Solvent-based paints add organic content that may affect the system sub-classification. For hospitality and public-space applications, specify a water-based paint system and confirm compatibility with the manufacturer if the project requires written assurance.

Are Kandes 3D gypsum panels suitable for hotel lobbies and public areas?

Kandes 3D gypsum panels are A1 non-combustible under EN 13501-1 and are CE marked. The Declaration of Performance is available on request. Kandes 3D gypsum panels are used in hospitality and commercial interior applications. The Kandes specification team can provide the full technical dossier — DoP, fire certificate, density datasheet — for projects with specific compliance documentation requirements.

Next Steps

For specifications requiring A1 compliance documentation, the Kandes technical dossier — Declaration of Performance, fire certificate, density datasheet, and panel-specific CAD files — is available on request from the specification team.

Download 3D models for your specification workflow. For installation guidance, text-based manuals covering all standard panel codes are at kandes.eu/pages/text-based-installation-manuals.

Sources

1. CEN — European Committee for Standardization. EN 13501-1: Fire classification of construction products and building elements. cencenelec.eu — the standard itself; cited as the definitive classification reference throughout.
2. RISE Research Institutes of Sweden. EN 13501 — European fire classification of construction products. ri.se — technical background of the Euroclass system; cited for classification criteria and the distinction between reaction to fire and fire resistance.
3. Eurogypsum — European Gypsum Association. eurogypsum.org — industry authority on gypsum material properties and thermal behaviour; cited for mineral composition claims.
4. Gypsum Association. Technical FAQs. gypsum.org — technical reference for gypsum fire performance; cited for endothermic mechanism.
5. European Commission. Construction Products Regulation (EU) No 305/2011. ec.europa.eu — legal basis for CE marking and Declaration of Performance requirements; cited in §2.
6. Measurlabs. EN 13501-1 Fire Classification: Performance Classes & Criteria. Updated February 2026. measurlabs.com — most complete current summary of the full Euroclass table; used to verify classification criteria in §1.