The simple answer is no: fire test evidence for service penetrations through standard symmetrical plasterboard walls cannot automatically be used for whitewalls or sandwich panel systems.
Before we explain this, let’s first look at what standard flexible wall evidence means. We will also clarify what whitewalls and sandwich panels are.
What are whitewall and sandwich panel systems?
'Standard flexible wall evidence'
This refers to fire-test evidence conducted in accordance with BS EN 1366-3, the fire-resistance standard for service penetrations.
It demonstrates that a firestopping system, such as a fire collar, retains its fire resistance when installed in a dry-lined stud partition rather than in a solid masonry wall.
Typical construction and materials
Although they have different names, whitewalls and sandwich panels are quite similar. A whitewall is essentially a type of insulated sandwich panel constructed from steel, with a rigid insulating core like mineral wool.
The main distinction is that not all sandwich panels meet the strict hygiene standards set out for whitewalls.
Offering a modern alternative to plasterboard stud walls and blockwork, they provide a single solution that combines both structural and insulating properties, reducing construction time and costs.
Common applications
Such systems are commonly used in laboratories, cold stores, and food factories, working best in temperature-controlled, hygienic environments.
More recently, whitewalls and sandwich wall panels have gained popularity in data centres, which are more common due to technological advancements in digital and AI.
Why are whitewalls and sandwich wall panels challenging from a fire testing perspective?
Limitations of current fire-resistance test standards
Right now, BS EN 1366-3 does not include these wall systems. Its section on interchangeability only covers plasterboard and blockwork – more on that later!
*The interchangeability section refers to the rules that allow test evidence for service penetration seals to be applied to different types of supporting constructions (so, walls or floors) without requiring a separate fire test.
The pace of modern construction vs testing frameworks
In fire testing, the main challenge is that the fire-resistance test standards do not keep pace with modern construction methods.
This happens for a few reasons: materials are developed quickly, the system is complex, and regulatory updates are slow.
Risks of misapplying evidence to non-standard walls
Therefore, evidence from standard symmetrical plasterboard wall tests cannot be applied to white walls or sandwich panels without further assessment.
If a fire occurs, wall systems respond differently, which can affect the fire seal’s performance. Without solid evidence, the potential fire safety risks of the reaction are unpredictable.
Can we test white walls or sandwich wall panels for service penetrations?
Explanation of BS EN 1366-3 Section 7.2.1
White walls and sandwich panels can be tested with service penetrations. It is often thought that only the wall types listed in Section 7.2.2 or in Table 2 of BS EN 1366-3 can be used. However, this isn't the case.
This is clarified in Section 7.2.1, which states:
The supporting construction may be either one of the standard supporting constructions listed in 7.2.2 or a specific construction. In the latter case, however, the field of direct application is restricted.
How testing specific constructions restricts the field of application
As Section 7.2.1 states, a specific construction type can be tested, but the overall scope of how that evidence is used will depend on what the accredited body decides when the evidence is:
- formally classified
- included in a field application technical assessment
*An accredited body is an organisation that has been formally recognised by a national accreditation body, like UKAS, as competent and compliant with standards to perform assessments.
Why early engagement is essential when specifying white wall penetrations
Risks if firestopping is considered late
Ultimately, fire stopping must comply with best practices and applicable legislation because these buildings are people’s homes, offices, and leisure spaces.
The main risk is always life, though the Gateway regime now helps combat old practices by creating stop-and-go points to ensure buildings are properly designed before construction.
Firestopping must always be designed in accordance with the manufacturer’s tested details. If it is not considered when critical decisions are made about service routes, there is no guarantee that the chosen manufacturer will have a suitable tested solution.
In this case, stakeholders may face risks, such as additional costs and delays, due to the need to redesign service penetrations, which can have knock-on effects on the entire project.
Overcoming coordination challenges with services and wall suppliers
The supplier knows their product best. They should be contacted early in the design process, ideally when the design is still a rough draft.
Working this way will ensure that each service penetration has an appropriate tested detail. It will also keep collaboration at the centre of the project to keep everyone on the same page.
This helps prevent overlooked grey areas that could lead to last-minute redesigns and keeps the project running as smoothly as possible.
How can Quelfire support your project?
Overview of Quelfire's tested white wall solutions
As part of our commitment to supporting the construction industry with primary test data, we have conducted extensive testing on a range of Euroclad and Paroc Panel System whitewall and sandwich wall panel systems.
Our primary evidence has been reviewed by an accredited body that conducted a technical assessment, resulting in a defined field of application for specific white wall systems.
These assessments enable our service penetration evidence to apply to specific systems, such as Euroclad Firemaster and Paroc Panel System AST F+, AST F, and AST L walls.
Our current range of solutions for service penetrations through these systems is available in the QuelSelector Solution Finder Tool
Using the QuelSelector to identify compliant solutions
The QuelSelector is our free fire stopping product selector tool, designed to simplify the specification process for construction professionals.
It helps users quickly identify the most suitable product for common service penetrations through fire-rated walls and floors, using fire stopping solutions.
If you plan to use these wall systems in your projects, contact our technical team early. This will help ensure you meet compliance.
