The 2017 Grenfell Tower tragedy permanently altered the UK construction sector. Deep-rooted systemic issues with building design, specification, and regulation were revealed by the ensuing public investigation.
Lessons learnt from Grenfell are still changing the building environment almost ten years later.
For developers, funders, insurers, and building control authorities alike, fire safety is of the highest importance, particularly with regard to the functionality of external wall systems.
As regulations have tightened, so too has the scrutiny. The days of aesthetic or cost-led facade choices are long gone. Today, every external wall system must be compliant and be able to prove its compliance, and this goes from the rainscreen panels to the smallest fixings and sealants.
Here, we look at what “fire-rated” really means in practice, and what you really need to know post-Grenfell.
What is a fire-rated cladding system?
A fire-rated cladding system is an external wall build-up designed and tested to resist the spread of fire. It’s not just about the outer panel; the fire performance of the entire system matters. This includes the cladding panels, insulation, cavity barriers, fixings and substructure. Together, they’ll show whether or not a facade is combustible and resistant to flame spread if there were a fire.
A fire-rated system undergoes stringent testing to demonstrate that it can restrict ignition, prevent flames from spreading, and maintain structural stability for a specified period.
Materials are given a classification after being tested, most notably BS EN13501-1. This classification ranges from A1, which is non-combustible, to F, for which no performance is determined.
While each product will have its own rating, a fully tested wall system will determine how each of the parts works together, not just one part of it.
UK Regulations for external walls in 2025
The UK’s laws governing the construction of external walls have changed significantly since the Grenfell tragedy. The Building (Amendment) Regulations of 2018 prohibited the use of combustible materials in exterior walls of high-rise buildings.
In 2025, UK regulations for external walls will be rigorously enforced through the Building Safety Act 2022 and the establishment of the Building Safety Regulator (BSR).
The use of flammable materials in exterior walls and certain attachments is currently forbidden by Regulation 7(2) of the building regulations. Buildings include:
- Those over 18 metres in height that contain one or more dwellings, an institution, or residential accommodation.
- Hospitals, care homes and student residences, regardless of occupancy type.
All materials in these external wall systems must achieve a minimum classification of A2-s1,d0 or A1 under BS EN 13501-1, with exceptions made for minor components such as gaskets, seals, and fixings.
Furthermore, with the new Gateway regime, there is a greater need for evidence of compliance before, during, and after construction. Developers and designers must give a clear “golden thread” of information, including fire performance data, test certificates, and system details.
Local Building Control and insurers are increasingly scrutinising facade designs at every stage. Facade specialists are essential from the outset to help avoid costly redesigns or delays later on in the building process.
Where fire-rated cladding systems are non-negotiable
While all new developments should consider fire performance from the outset, there are specific building types and situations where non-combustible, fire-rated cladding systems are absolutely non-negotiable.
These include:
- High-rise residential buildings over 18m (11m in Scotland)
- Hospitals, care homes, and schools, where vulnerable occupants need enhanced protection
- Student accommodation and hotels, due to high occupant density
- Mixed-use developments combining residential and commercial spaces
- Refurbishments or recladding projects on existing buildings are identified as high-risk after post-Grenfell reviews
What makes up a fire-rated facade
A fire-rated facade is more than just non-combustible cladding panels, it’s a system of layers that each have a role in resisting fire spread.
External cladding panels
The outer lead of a facade is the most visible element in fire performance. In a fire, the cladding panels can act as either a barrier or a pathway for flames to spread vertically up the building envelope. That’s why the choice of panel material is critical.
- Buildings over 18 m must have A1 or A2-s1, d0-rated panels as standard.
- Aluminium and steel rainscreen systems combine durability and flexibility with full compliance under BS EN 13501-1.
Insulation, sheathing and backing walls
Behind the outer leaf sits the insulation and sheathing. Post-Grenfell the use of combustible insulation is heavily restricted on taller residential buildings.
Current guidance from GOV.UK and industry bodies makes it clear that only non-combustible insulation, typically mineral wool or stone wool, should be used in buildings above 18 metres.
Subframe and fixings
The supporting subframe connects the rainscreen panels back to the primary structure. Typically, this is made from aluminium or galvanised steel; these frameworks must also be assessed for fire performance and compliance.
All subframe components and thermal isolators must either meet A1/A2 classification or fall within specific exemption limits that are outlined in Regulation 7(2).
Cavity barriers, fire-stopping and compartmentation
Behind every ventilated facade lies a concealed cavity; it’s an essential feature for moisture control and a potential “chimney” for fire spread if left unprotected.
- Continuous, correctly installed cavity barriers are vital for maintaining compartmentation.
- Barriers must be both vertical and horizontal to close off cavities at floor levels, party walls, and around openings.
- Fire-stopping junctions between the face and other building elements ensure no weak points remain.
Interfaces and details
Interfaces around windows, doors, balconies, parapets, and roof junctions all make up a fire-rated cladding system. For developers and contractors, attention to detailing is the difference between theoretical compliance and genuine fire safety.
Compliance needs to be done down to the smallest of things. Small errors in these areas could include:
- Gaps in cavity barriers
- The use of combustible sealants
How Pops Facades supports safe, fire-rated cladding systems
Pops Facades offers the following services from initial development and specification through installation and inspection:
- Technical advice for choosing subframe, insulation, and cladding systems that comply.
- System integration knowledge to ensure that each part functions as expected.
- Clear documentation to support building control approval and Gateway submissions.
- Proven track record in delivering new-build facade and recladding projects safely and efficiently.
You can be assured that your external wall systems will withstand the test of time and comply with the latest Building Regulations when Pops Facades is your partner. To discuss your façade needs or schedule a consultation with our technical staff, please get in touch with us now.
