What is SFS?

What does SFS stand for?

In the construction industry, SFS stands for Steel Framing System.

In its broadest interpretation, a Steel Framing System could be seen as any system of steel components (columns, beams, trusses, fixings, etc.) which can be used to create a framed structure, from a garden shed to a multi-storey office building.

However, the construction industry now widely accepts SFS as being an infill system for primary structures which is used to support the building’s façade systems. SFS comprises studs and tracks, which are precision-engineered from light-gauge cold-rolled steel, together with associated fixings and accessories.

This Steel Framing System is a highly efficient, versatile construction solution which can be used in a variety of loadbearing and non-loadbearing situations, including external walls on concrete/steel framed buildings, continuous walling, lightweight structures and dividing walls in high bay situations.

SFS is primarily installed ‘stick built’ on site and is particularly well-suited to modern methods of construction which deliver significant benefits to a project in the form of time and cost efficiencies and return on investment.

Steel framing system components are also used in factory fabricated, pre-panelised construction systems, such as our own Metframe, where frames are assembled remotely from the construction site, complete with requisite insulation material and sheathing boards, ready for immediate installation and use on site.

What is SFS made from?

As the name suggests, steel is the raw material used in the manufacture of Steel Framing Systems. However, rather than the heavy sections created by the hot rolling process, the steel sections used in SFS are manufactured from light gauge steel through cold rolling.

Coils of galvanised light gauge steel (Starting at 1.2mm gauge) are loaded onto a computer-controlled cold rolling line. The steel is cut to lengths dictated by contract and production schedules and then passed through a number of stations in which gentle pressure is applied to the steel by a succession of rollers to form it into the required section. No heat is applied to the steel during this process, hence the term ‘cold-rolled’. Studs are formed as a ‘c’ (with a small returning lip) which gives them coaxial strength through the section.

The result is a lightweight, high-strength member (stud or track) that can be used in a wide variety of loadbearing and non-loadbearing situations.

What are the benefits of SFS?

SFS delivers benefits to all stages of the construction process, from design to installation, as well as providing the client with the prospect of realising returns on investment at the earliest opportunity.

How does SFS benefit design?

SFS provides architects, designers and engineers with enhanced flexibility when it comes to the design, appearance and performance of the building.

Whilst commonly thought of as an infill system in multi-storey concrete and steel framed structures, SFS is extremely versatile, offering potential far beyond a simple infill solution. In addition to infill walling, its applications include ceiling, roof and floor joists, continuous walling, freestanding parapets and loadbearing structures.

The potential to combine SFS with a wide variety of different insulation materials, as well as internal and external sheathing/cladding, facilitates freedom in creative expression and building layout.

Choosing Metsec SFS does not impose limitations on the choice of wall or façade materials that can be used, allowing designers to select materials which achieve the desired fire, thermal and acoustic performance for a structure.

Additionally, with steel sections being easily cut to size, specific design requirements can be accommodated within a project’s production schedules, providing enhanced design freedom in the appearance and layout of the building.

Steel Framing Systems also enable structural engineers to design lighter weight buildings, which reduces demands on foundations and structures, with consequent savings in materials and time. SFS also significantly reduces the amount of carbon required to form the primary structure.

The lightweight structures which SFS delivers can also be used to create additional accommodation at the top floor level of multi-storey structures or for improving existing buildings where loadings might prevent the use of traditional construction methods.

How does SFS benefit the construction process?

Once delivered to site, SFS components are quickly and easily assembled into frames for installation and ready to accept infill boards and facing panels immediately. This ensures that a structure is rapidly weather-tight and reduces the time it takes for follow-on trades to commence their work.

The installation process itself is straightforward, with techniques requiring minimal skilled labour.

Installation is further simplified by coding stamped onto components, particularly when using Metsec SFS where stud is marked with a small stamp detailing depth, flange and gauge of steel and colour coded for ease of selection and assembly.

Colour coding stud also ensures that the project extracts maximum benefits from the value-engineered solution which has been designed. For example: In situations where greater strength is required, such as around window jambs and doorways, a normal solution would typically be to box stud together to form a compound section. This can be a costly option. At voestalpine Metsec, the colour coding is used to denote a thicker gauge of steel, obviating the need for ‘boxed’ compound sections and assuring a more cost-effective solution.

How does SFS save time and costs?

The time and cost saving benefits of SFS start at the pre-design stage and progress through to final installation and commissioning of a building.

Initial consultation with experienced sales staff and highly skilled engineering teams helps to determine the most appropriate solution for a project. Once the objectives of the client and designer are established, design of a value-engineered solution commences, utilising the most efficient approaches to production, construction scheduling and installation.

Typically undertaken using specialised CAD systems (voestalpine Metsec has its own Revit-based design software (sign up for free access)), with full capacity to work in Revit for BIM projects, this design process affords a great deal of precision which translates readily to the production of the SFS track and stud required for the project, assuring precisely engineered product, timely manufacture and minimal wastage.

Time and cost efficiencies are further realised through the accurate scheduling and delivery of the Steel Framing System to site and its ultimate installation; components can be manufactured and delivered to exact construction schedules, whilst installation can commence immediately the SFS components are delivered to site.

With no reliance on wet trades, Steel Framing Systems are simply screwed together and connected to the primary structure with either shot-fired nails or self-drilling screws to a steel frame, or concrete screws to a concrete frame. Once installed, SFS is ready for immediate use, ensuring that follow-on processes can be commenced without delay.

How does SFS speed return on investment?

The benefits that SFS brings to the design and construction of a building translate readily into quicker and greater return on investment for the developer.

The cost savings afforded by value engineered SFS solutions naturally offer the potential for increased margins and improved return.

The fact that SFS enables buildings to be finished and ready for occupation more quickly means that developers can start to realise these returns at an earlier stage than might be achievable through traditional construction methods.

In addition, SFS delivers a high degree of precision and is not subject to shrinking or creeping once installed, assuring a quality finish and reducing maintenance.

How does SFS improve safety on site?

SFS makes a substantial contribution towards the overall safety and operating efficiency of the construction site. In addition to its light weight and ease of handling, the system minimises waste on site and requires minimal numbers of personnel to install. These factors significantly improve health and safety outcomes, with much less propensity for accidents.

How to maximise the benefits of SFS?

voestalpine Metsec offers a comprehensive pre- and after-sales support and design package, including 3D modelling and BIM-compliance, to ensure that designers, contractors and developers maximise the benefits that SFS can deliver.

Early engagement is key to realising these benefits. voestalpine Metsec’s initial design services are available free of charge and with no commitment, enabling the project team to assess the benefits of using SFS at the project’s conception and without risk.

Is SFS a sustainable product?

The simple answer to this question is a resounding ‘Yes!’

The sustainability credentials of SFS are widely recognised throughout the construction industry. Not only do Steel Framing Systems facilitate the reduction of carbon emissions in the construction process, but they also offer the potential for 100% recyclability at the end of a building’s use.

How does SFS reduce carbon emissions in construction?

Using SFS to construct new buildings or to refurbish existing buildings offers the potential for the construction industry to significantly reduce carbon emissions in a variety of ways. These include:-

Lower embodied carbon

‘Embodied carbon’ refers to the total carbon emissions associated with the production, transportation, and construction of building materials. Using SFS reduces the demand for raw materials, particularly when used to refurbish a building. The lightweight steel framing places less demands on foundations and structures for new buildings. This means that less total material needs to be manufactured and transported, leading to a reduced carbon footprint.

Less waste generation

We have already spoken about SFS’s ability to minimise wastage and to reduce the requirement for wet trades on site, as well as the reduced requirements placed on foundations and structures.

Using SFS in the refurbishment of buildings offers further potential to reduce materials wastage. It can also reduce the amount of carbon that is embodied within existing building materials that might be returned to the atmosphere when buildings are demolished. By using SFS to refurbish the existing structure, this carbon storage can be preserved, and the waste generation of the construction is minimised.

Reduced transportation emissions

Being both lightweight and efficiently bundled, SFS helps to keep transportation emissions to a minimum. It requires less deliveries than competing construction systems, such as blockwork, and is considerably lighter in weight.

Getting material to site is significantly easier with SFS: (Studies have shown that for 4000m² façade, 56 trucks were required when using traditional block, whereas SFS required just 2.

Energy efficient upgrades

In refurbishment projects, SFS provides an opportunity to implement energy-efficient upgrades. SFS allows for the integration of improved insulation materials and energy-efficient cladding systems. Improved insulation, efficient windows and climate-responsive design can help reduce the building’s energy consumption for heating, cooling and lighting. By making the building more energy-efficient, the overall operational carbon emissions are lowered.

Less disruption

Using SFS in the construction of new buildings or in refurbishment of existing ones typically involves less disruptive construction, shorter construction periods and reduced emissions related to the building process.

Recyclability

Steel is one of the most readily recyclable of building materials. Not only is SFS made entirely from steel but it is also screwed/bolted together, making removal and reuse quick and easy.

Where can SFS be used?

Steel Framing Systems can be used in a wide variety of different structures, such as concrete or steel frames, with a wide variety of infill and facing materials, from mineral board to architectural glazing, and for loadbearing and non-loadbearing situations.

SFS is also suitable for continuous walling and high bay walling applications.

SFS as infill walling

See our infill solutions here.

One of the most economical means of providing infill walling in concrete and steel framed structures, SFS provides a floor to soffit solution to infill the exterior wall zone of a building.

The Steel Framing System provides the framework and support required to accept insulation materials, internal wall boards and external cladding systems.

A base track is fixed onto the slab of the primary structural frame. Slotted head tracks are then fixed to the underside of the slab or structure to allow for deflection, and studs are then cut, aligned and fixed into position at regular centres with Tek screws to provide support for internal and external finishes.

SFS in loadbearing applications

See our load-bearing solutions here.

Suitable for low to medium rise buildings of up to five storeys in height, SFS can be assembled on site in stick-built construction to create the structural framework for walls, floors and roofs.

SFS as continuous walling

See our continuous walling solutions here.

In continuous walling situations, SFS is used as a framework to support external cladding systems. Oversailing the slab edge, this solution allows designers to maximise available floor space within a building and obviates the need for cladding to bridge deflection joints at each floor.

The system requires support at its base with SFS track and stud being constructed as a supporting frame to multiple storeys high. The frame is restrained using cleats with slotted connections at each slab level.

SFS for high bay walling

See our high bay solutions here.

Used to create high separating walls in factory units or atriums, SFS provides a fast-track, high performance solution for walls up to 20 metres high. Lightweight construction and evenly distributed loads normally allow SFS to be used within existing structures without the need for additional strengthening of foundations or floor slabs.

What types of buildings can SFS be used on?

Steel Framing Systems can be used on a wide variety of building projects where rapid, lightweight and cost-effective construction is required.

Factory-controlled manufacture and quick installation make SFS highly suitable for Modern Methods of Construction, with consequent advantages and benefits.

The versatility of SFS has seen it used in the design and construction of hospitals, schools, retirement homes, apartment blocks, student accommodation, hotels, offices and many other projects which demand a quick turnround, whether for use or return on investment.

SFS vs. blockwork – How does it compare?

An independent study comparing SFS and blockwork as the internal wall of a building in four separate façade scenarios proved SFS to be quicker to build, to increase sustainability performance and to significantly improve cost efficiency.

Key findings of the study showed:-

• In a typical week, with two teams of three installers, SFS can offer 124m² greater coverage than blockwork, with 4 teams of bricklayers.
• SFS reduces the installation programme by three weeks.
• SFS requires up to 25x less lorry deliveries to site – 2 lorry loads compared to up to 56 lorry loads for blockwork.
• SFS returns 95% less wastage than blockwork.
• SFS delivered cost savings of:-
• 4% on total build cost.
• 13% average saving on through wall cost.
• 33% against comparable elements.

How do I design with SFS?

With more than 50 years of experience in the design and manufacture of lightweight steel framing systems, voestalpine Metsec has developed a highly effective and efficient approach to SFS design which eases the burden on the project’s design team and assures the on-budget delivery of buildings to precise specifications.

The voestalpine Metsec design process can be neatly summarised in three stages:-

Stage 1: Specification guide

Our dedicated specification guide (available as literature or via the website) provides load tables which allow stud sizes to be determined based on vertical spans and local wind pressures, together with wall build-up data for the desired performance characteristics, including fire, thermal and acoustic. This facilitates the selection and configuration of the SFS products which provide the optimum value-engineered solution.

Stage 2: Design specification

Free of charge and without obligation, our qualified and highly experienced team of engineering designers provides the engineering input to establish the most efficient stud configuration and details on how a project’s specific requirements will be handled, including openings, façade, balconies, etc.

Stage 3: Full detailing

On client commitment, voestalpine Metsec provides full detailing whereby our in-house engineering team provides the precise set-out for every stud location in preparation for installation.

What are the performance characteristics of SFS?

With steel framing systems, fire performance, thermal and acoustic efficiency are achieved through the combination of materials that are used in conjunction with SFS to construct the wall. For external wall constructions, from inside to out, this would typically consist of dry lining, SFS (possibly including insulation within), sheathing board and insulation. The final wall construction can vary according to the external façade materials that are used, which can range from brickwork to insulated render, timber cladding, composite panels, ventilated rainscreen and many others that might be selected to achieve the desired exterior finish or budget.

The widely recognised term for the functionality of these various components, is ‘through wall performance’; i.e. the properties of the zone from the inside face of the internal dry lining to the outside face of either the sheathing board or insulation.

Fortunately, voestalpine Metsec makes the selection and specification as simple and painless as possible by providing comprehensive performance data on SFS when used with a wide variety of proprietary insulation and facing materials, all supported by independent test evidence.

What is Z600 finish in SFS?

The National House Building Council’s (NHBC) moisture control standards for light steel framing in new residential buildings (including houses, apartments, student accommodation and care homes) states that the structure should be adequately protected from the effects of moisture where light steel framing is used at low level.

Where steel protection is concerned, the NHBC now stipulates that the base rail of the steel framing should either be 150mm above external ground level (or waterproofing layer of a balcony, flat roof or terrace) or, where the rail or lowest steel is less than 150mm above this level, additional protection of the steel should be considered. Metsec SFS is available in Z600 galvanised steel section which achieves the NHBC’s requirement for a 60-year design life.