Whilst balconies remain a key requirement in residential developments, their integration into masonry and rainscreen façade systems introduces a complex firestopping challenge. Steel support brackets, fixed back to the floor slab, interrupt what should be a continuous compartment line. In many cases, these brackets extend across the full slab depth, leaving insufficient space to maintain effective cavity barrier continuity. In a façade fire, exposed steel brackets can heat rapidly, potentially affecting structural performance while also enabling heat transfer to combustible materials on the balcony.
For specifiers, addressing this detail has often relied on project-specific solutions. Cavity barriers may be positioned below the bracket, subject to fire engineering justification, or notched around brackets, base plates and bolts. However, these approaches are heavily dependent on installation accuracy and frequently lack supporting fire test evidence. The consequence is a reliance on site trials, benchmark installations, and ongoing consultation with Building Control—factors which can delay programmes and introduce uncertainty.
A shift towards more standardised detailing is helping to address this issue.
The Siderise BB FB Balcony Bracket Fireboard has been developed as a pre-engineered system to simplify the interface. Using pre-cut or site-cut interlocking stonewool fireboards, the system encapsulates the steel bracket at the slab edge, enabling cavity barriers to be installed continuously on either side. This removes the need to design around the bracket and instead incorporates it within a defined fire protection strategy.
The system has been tested to EN 1366-4: 2021 across a range of configurations, achieving a 120 minutes integrity and 120 minutes insulation fire resistance performance. Unlike traditional approaches, testing has been carried out as a complete system alongside adjacent cavity barriers, providing a more representative assessment of in-situ performance. This evidence base is particularly valuable when supporting compliance at Gateway 2, where clarity and traceability of design decisions are essential.
From a delivery perspective, the use of pre-configured components reduces reliance on site-led interpretation, improving installation consistency across repeated floors while reducing labour intensity. This supports better quality outcomes and more predictable project timelines.
Specification is supported by CCPI-aligned product information, validating clarity and reliability of technical data. In addition, the BB FB Testing Information Pack translates fire test results into practical design guidance, including coordinated 2D section details and 3D visualisations to illustrate tested arrangements. This helps reduce design risk and supports robust documentation within fire strategies.
As the industry continues to prioritise safer buildings, the ability to standardise complex façade interfaces is becoming increasingly important. By converting a traditionally bespoke and variable detail into a tested and scalable solution, systems such as Siderise BB FB provide specifiers with a more reliable path to demonstrating compliance while maintaining buildability.
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