Spec Finish

Technical A new FIS Guide has been written to outline the standard definition of ‘through-wall’ and will help in their design, specification and installation. THROUGH-WALL 12 www.thefis.org T HROUGH-WALL’ has become a generic term used by suppliers of systems to describe infill exterior walls constructed from light gauge steel frame (LGSF) – sometimes described as steel framing systems (SFS) – where frame, inner plasterboard and external sheathing boards are tested and sold as a system. However, in a similar way that the framing can be defined as LGSF and SFS there is no consistency in what constitutes through- wall and that’s why we are publishing a new through-wall infill SFS Systems Guide. The guide has been drafted by a panel of experts from the FIS SFSWorking Group in conjunction with the Steel Construction Institute (SCI), to explain the three options: 1. From inner plasterboard to external sheathing board. 2. From inner plasterboard to external sheathing board and external wall insulation. 3. From inner plasterboard to external sheathing board, external wall insulation and façade system. AndrewWay, Associate Director at SCI, said: “The term ‘through-wall’ (with various spellings and abbreviations) has been in common use in the construction industry for many years now but its precise meaning is still unclear for many people. This is not surprising as a recognised definition of through-wall has not been provided until now. This joint publication from FIS and SCI addresses the need by providing a clear definition and presenting useful information about the topics and performance characteristics related to through-wall systems. The leadership of FIS in driving this publication has been critical for achieving this new guide for the industry. “Steel has become the market-leading material for this application because of its quality, speed of installation, and design versatility. When correctly specified and installed, through-wall systems can provide the necessary fire resistance and weather tightness of the wall.” “Through-wall is interpreted in different ways by different product manufacturers and contractors” added the Managing Director of the Purlins and Framing division at Voestalpine Metsec, Stephen Ginger. “Significant focus should be given to tested wall solutions; aligning manufacturers’ products, ensuring that the whole wall construction is robust, transparent, and safe so the specifier can clearly understand the performance of the through-wall solution and ensure it meets the specific application.” Colin Kennedy, Chair of the FIS SFS Working Group, said: “This guide has been produced to provide a standard definition of through-wall and assist in the design, specification, and installation of SFS through-wall systems.” Alex Double, Managing Director of A D Design Consultants (ADDC), was tasked with drafting the guide and said: “It’s really important that specifiers and contractors fully understand that the term through-wall should be treated in the same way as a description such as ‘car’ or ‘house’ - they encapsulate the thing but there is no detail of the makeup or all the performance. For example, the inclusion of a vapour control layer may be a significant component on a test for one solution yet not required in others. “Through-wall still has different meanings to different people, and the term does not describe the detail, make up, or performance of the external wall system. This guide will assist specifiers and contractors to better understand what through-wall is.” FIS Technical Director, Joe Cilia, added: “LGSF, SFS and through-wall are still emerging technologies and solutions as part of Modern Methods of Construction (MMC). It’s vital that their integration and interface into the building structure to ensure the performance requirements can be met, and what clear evidence of compliance is required, is addressed as early in the design stage as possible.” The guide is aimed at everyone in the delivery chain from design to specification, fire engineers, contractors, site managers, and installers. It will be freely available from SCI and FIS at ( www.thefis.org/membership- hub/publications/best-practice-guides/ through-wall/ ) and will be used to form the basis of continuous professional development programmes going forward. Joe Cilia, FIS Technical Director Through-wall section drawing ‘