Understanding Fire Performance Ratings
Understanding the fire performance of construction materials is critical in modern building design. Architects and contractors must ensure every component performs safely under fire conditions, particularly in public buildings, transport hubs, high-rise developments, and areas with strict Building Regulations oversight.
Architectural mesh — whether stainless steel, aluminium, or phosphor bronze — is often selected for its strength, openness, airflow, and visual transparency. But just as importantly, it is selected for its exceptional fire performance. At Locker Architectural, we support project teams by providing clear documentation and advice at the earliest stage so specifications can be made with complete confidence.
This article outlines how architectural mesh behaves in fire, how it is classified, and what specifiers need to consider when designing with metal mesh systems.
Fire ratings for Cladding and Juliet Balconies in High Rises
Since the Grenfell tragedy in 2017, the materials used to construct high rise buildings have been under incredible scrutiny.
Architects and specifiers are now acutely aware that the materials they specify must carry the appropriate fire rating, lest they end up like Studio E, the architectural practice in charge of the Grenfell tower refurbishment in 2015-16.
Studio E filed for liquidation after becoming embroiled in a lawsuit and unable to afford legal representation at the Grenfell Tower inquiry.
Fire Ratings Made Simple
The UK Building regulations on fire safety were issued in 1991 and use (from best to worse) Class 0, 1, 2, 3, 4 ratings to classify materials. However, since then, the UK Government has adopted the far more thorough and exhaustive Euroclass system:
- Class 0 is not a fire classification identified in any British standard test. Despite that fact, people still incorrectly cite Class 0 – 4 when talking about Fire Ratings.
- European fire ratings (Euroclass) are (from best to worse) A1 , A2, B, C, D, E or F.
- Smoke emissions are indicated using a (from best to worse) S1 , S2, or S3 rating.
- Smoke classifications are not given to products with an E or F Euroclass rating.
- Flaming Droplets/particles are indicated (from best to worse) using a d0, d1 or d2 rating.
- A1-rated products are not given a smoke or flaming droplet rating, as it is assumed they do not contribute to fire growth or spread.
The building (Amendment) Regulations 2018 specifies that materials used for and attached to the external wall of buildings 18m+ high must achieve Class A2-s1, d0 or A1 in accordance with BS EN 13501-1:2007+A1:2009 (later superseded by BS EN 13501-1:2018).
The UK Government is also exploring a proposal that would further include 11m+ high buildings.
What does this have to do with Juliet Balconies and Cladding?
Though it wasn’t applied retrospectively, this effectively resulted in a ban on the future use of laminated glass infill panels for balustrading and Juliet balconies in high rises, as they fail to achieve the necessary fire rating.
As of today, there are few companies who have managed to achieve this fire rating using glass materials. Those that have are offering a product which is too expensive to be practical. At the time of writing, none have ever managed to achieve an A1 rating.
Just in case you were wondering – the glass panes in windows and doors are specifically exempt from this rule and can be made using laminated glass.
Locker Architectural Products
EU Publication 96/603/EC lists materials that are class A1 rated without fire testing (provided they are not finely divided) inclusive:
Locker Architectural metal meshes are generally made entirely from aluminium or stainless steel before the introduction of a secondary finish.
This means that they are automatically classed as A1 fire rated and can safely be specified for high rise buildings, be it Juliet balconies, façade cladding, rain screening, sun screening etc.
How Do The Different Metals Compare?
Stainless Steel Mesh
- Fully non-combustible
- Melting point ~1400°C
- Suitable for internal and external fire-sensitive environments
Phosphor Bronze Mesh
- Also non-combustible
- Used in applications where colour shift and patina are design features
- Fully compliant for internal and external applications
Key Standards Referenced by Architects & Fire Engineers
- EN 13501-1 – Reaction to fire classification
- BS 476 Part 4 – Non-combustibility test
- BS 476 Part 6 – Fire propagation
- BS 476 Part 7 – Surface spread of flame
- BS EN 12101 – Smoke control systems
- Approved Document B – Building Regulations
- NHBC & warranty provider requirements for façade materials
Locker supplies material certification and fire documentation for every project.
How Fire Performance Influences Mesh Selection
1. Façades and Solar Screens
Mesh used externally must satisfy façade fire requirements, particularly for high-rise buildings. Stainless steel, aluminium and bronze meshes are all suitable in A1 or A2 form.
2. Ceilings and Soffits
Mesh can be installed directly beneath sprinkler systems or lighting. Because it is non-combustible, it allows water and smoke to pass through without disrupting system performance.
3. Transport Hubs
Railway stations, airports and metros often require A1 materials due to high occupancy and escape routes. Woven and expanded mesh are frequently selected because they meet these requirements naturally.
4. Balustrades and Infill Panels
Mesh used as a safety barrier must deliver both fall protection and fire compliance.
Locker supplies mesh that satisfies both performance criteria simultaneously.
5. Plant Screens & Data Centres
Mesh here is chosen for:
- fire safety
- high open area
- airflow performance
- heat dissipation
How Locker Supports Fire Compliance
1. Early Project Involvement
Your technical directors (Andrew, Adrian, Dave, Tom) review the mesh, substructure, and coating requirements directly with architects and fire consultants.
2. Clear Technical Documentation
Mesh certifications, coating data, fixings, and substructure materials are supplied with every quotation.
3. System-Level Problem Solving
Your team highlight risks such as:
- Non-rated timber backings
- Incorrect acoustic fabrics
- Non-rated paints or lacquers
- Obstructive lighting layout
- Powder-coating incompatibilities
4. Collaboration With Fabricators
Locker ensures installers understand fixing methods that avoid sparks, heat, or contamination during installation.
5. No Surprises at Handover
All information is aligned with Building Control and the fire engineer’s expectations.
This is exactly the approach that has made Locker a trusted partner in transport, infrastructure, arts venues, public buildings, and high-end commercial architecture.
Contact our team for more information
If you are looking to specify mesh for a large-scale cladding project or building envelope, and you have concerns over the fire safety of your specification, contact our sales team for a more in-depth discussion.
Click Here for details of our full product range, or phone 01925 406600.
