What does code 921 actually set?
Israeli Standard 921 (ת"י 921) governs the reaction to fire of building materials: how much a material contributes to a fire, how much smoke it emits and how it behaves under fire exposure. It classifies the material using a methodology parallel to the European standard EN 13501-1, and in facade cladding it is the basis for determining the panel core grade.
This is the point that confuses most building owners, so it is worth stating plainly: the standard classifies the panel, the regulation decides which classification is required. The actual requirement is set in the project specification. We build to it, and we never install a PE core.
What to check in a quotation before you sign
Fire safety in cladding lives in the detail of the quotation, not in its heading. These are the lines worth demanding from any bidder, and they appear in ours by default:
- Core grade in writing: FR or A2, not "meets the standard" with no detail.
- Manufacturer certificate: with the EN 13501-1 classification, verifiable with the manufacturer.
- Manufacturer name and series: not "Alucobond or equivalent".
- Fire stops and floor-to-floor detailing: part of the system, not an extra.
- The support system: profile material, fastener grade and the metal-separation detail.
The grade is stamped on the back of every panel and stated on the manufacturer specification certificate. A contractor who will not hand that over before signature is a reason to stop.
Which panel grade does each building height require?
Code 921 classifies how a material reacts to fire. The grade for a given project is set in its specification. On most buildings, FR (Fire Retardant) panels with mineral fire retardants in the core are the customary specification. Above it, and for public buildings such as hospitals and schools, A2 panels with fully mineral cores are required.
Polyethylene (PE) cores are not compliant for any building above one story, regardless of other safety measures.
Installation system requirements
The standard requires more than just compliant panels. The full installation system must include engineered fire stops at every floor level within the ventilated cavity, around all wall openings, and at the building base and roof line. These fire stops prevent fire from propagating vertically within the cavity behind the panels.
The hardware itself (brackets, rails, fasteners) must be made of non-combustible materials, typically aluminum or stainless steel.
Insulation in the cavity
Any insulation placed within the ventilated cavity must itself be non-combustible. Mineral wool is the standard choice. Polystyrene and other plastic-based insulations are not permitted within the cavity, even if the panels themselves are compliant.
This is a frequent area where non-compliant installations are caught during inspection. The visible panel may be compliant, but a hidden polystyrene insulation invalidates the entire system.
Documentation required
Every code-921 project requires documentation that travels with the building. Owners and building managers should retain:
- Panel certification from the manufacturer, with the fire rating clearly stated
- Installation system specification from the contractor
- Engineer-stamped facade drawings showing fire stop locations
- Insulation specification with non-combustibility certification
- Final compliance certificate from the supervising engineer
How do you verify your project complies?
Three questions to ask your cladding contractor before signing. A hesitant answer to any of them is a reason to stop and check.
- What is the panel classification under EN 13501-1, and can I see the manufacturer certificate now?
- Exactly where are the fire stops marked on the facade drawings?
- Who signs the final compliance certificate, and when is it handed over?
Key takeaways
- Code 921 classifies the material. Regulation decides which class your building needs.
- We specify FR or A2 only, and never a PE core.
- On towers, public buildings, hospitals and schools: A2 mineral core.
- Cavity insulation must be mineral and non-combustible. Polystyrene voids the system.
- The core grade is set in the project specification. We build to it and supply the manufacturer documentation.
On a residential project? See cladding for residential buildings and towers. On an office building? See cladding for office and hi-tech buildings. For the wider picture of every cladding system on the Israeli market, see our complete exterior wall cladding guide.
Frequently asked questions
Is Alucobond fire resistant?
It depends on the core. A2-core panels are classified non-combustible under EN 13501-1 and do not contribute meaningfully to a fire. FR panels contain roughly 70 percent mineral fire-retardant filler and substantially limit flame spread. PE panels with a pure polyethylene core are combustible and are not suitable for the facade of an occupied building.
Up to how many storeys can FR panels be used?
The answer sits in the project specification. On most residential, office and retail buildings FR is the customary specification; on towers, public buildings, hospitals and schools it is an A2 mineral core. We specify FR or A2 only and never a PE core.
Is code 921 the same as European EN 13501?
They are related but not identical. Israeli code 921 addresses reaction to fire of building materials using parallel testing methodology, but some requirements are phrased differently. A panel with a valid EN 13501-1 classification is the starting point of the check, not the end of it. Always verify the certificate with the manufacturer and with the Standards Institution of Israel.
What happens if a building is found non-compliant?
New construction will not receive its occupancy approval. An existing building found non-compliant on inspection may be required to replace the cladding. Replacement cost includes removal, disposal and access equipment, and typically exceeds the cost of correct installation by a factor of three or more.
Does the requirement apply to renovating an existing facade?
Yes. Once cladding work begins, whether on new construction or a facade renovation, the current requirements apply. Existing legacy cladding may remain until renovation, but you cannot replace part of it with a specification that does not meet the current requirement.
