As the need for immediate action becomes more pressing, fibre reinforced concrete can be adopted today, offering significant savings when considering Embodied Energy (EE) and CO₂.
There are a wide range of applications where fibre reinforced concrete can be adopted, providing cost-effective and environmentally friendly solutions.
Taking values from the published Inventory of Carbon & Energy (ICE) Version 1.6a – University of Bath, an assessment of the benefits in comparison to traditional mesh and bar reinforcement can be made.
Composite Metal Decks (CMD)
Fibre Concrete Solutions’ Apex 60 steel fibres are approved by the Steel Construction Institute for use in concrete in CMD construction on decking supplied by SMD, Tata, Metflor and Kingspan, for fire ratings up to and including 120 minutes.
Replacing mesh fabric with Apex 60 steel fibres can reduce EE/CO₂ by between 30% and 50%, when considering a direct comparison between the relevant fibre dosage and mesh type, along with the additional handling and cranage effects. As the concrete thickness on the decking cannot be reduced by the addition of fibres – and concrete represents the highest EE/CO₂ parameter – the specific replacement of mesh with fibres still offers a 10-19% reduction in EE/CO₂.
Being able to replace mesh reinforcement with fibre reinforced concrete brings numerous benefits to the construction process, including reducing multiple material handling operations on site and the risks associated with cranage, handling and placement of reinforcement across multiple elevated floors. Replacing traditional mesh in this way delivers time and health and safety benefits, as well as considerable savings.
Main contractors frequently appoint sub-contractors for the supply and fix of the concrete deck, often considering only the labour and material costs proposed when awarding the contract – without realising that their hired lifting equipment will still be required to lift the mesh into place, requiring many hours of costly cranage time at the main contractor’s expense.
Whether considered specifically or across a whole project, replacing traditional reinforcement mesh with Apex 60 steel fibres delivers environmental benefits today.
Industrial Floors
The design of industrial floors is well documented, with guidance provided by Technical Report 34, published by the Concrete Society. FCS has used fibre reinforced concrete to provide robust design solutions for both ground- and pile-supported slabs, with the added benefit of eliminating not only the need for traditional mesh fabric, but also the need for sawn induced joints and joint sealant – a major source of repair and maintenance issues for industrial floor slabs.
The environmental benefits of adopting fibre reinforcement are enhanced further by the potential to reduce slab thickness while maintaining an equivalent load-carrying capacity.
Current typical industrial floor slabs are designed at 200mm thick, with a single bottom layer of A193 mesh reinforcement, cast using laser-controlled screeding machinery, with sawn cuts dividing large panels – one quarter to one third of slab depth – every 6m. FCS contends that, to comply with the percentage area of steel below sawn joints as guided by TR34, A193 mesh should in fact require a minimum slab thickness of 210mm – a debate explored further in FCS’ blog “To Saw or Not to Saw”, available on our website or in the June 2026 edition of Concrete magazine.
By comparison – and accepting the current 200mm thick design with A193 bottom mesh, following the same design parameters set out in Concrete Society TR34 4th edition – a fibre solution using FCS Apex 60 steel fibres at a dosage rate of 30kg/m³ could reduce the required slab thickness to 160mm, without the need for saw cuts or practically undeliverable offset distances for racking installation.
This would result in EE reducing from 632 MJ/m² to 562 MJ/m² – a saving of 11%, not including the multiple handling operations on site.
This figure would be enhanced further by potential savings to cut-and-fill operations and sub-base preparation on site.
External Slabs and Pavements
The adoption of fibre reinforced concrete for external yards is another proven solution.
Where slabs are subject to HGV loadings, designs can be checked for the relevant axle movements to ensure compliance with fatigue requirements.
In many instances, FCS Nexus 85 synthetic macro fibres can be adopted at a dosage rate of just 2.25kg/m³.
Where Nexus 85 is adopted, EE savings are increased further when considering fibres as an alternative to traditional mesh fabric, with a 45-80% saving in MJ/m². The presence of fibres also improves the impact and abrasion resistance of the concrete surface and eliminates the potential loss of cover to steel bar reinforcement – crucial for maintaining passivity and corrosion resistance, which might otherwise lead to oxidisation, expansion and further cracking of the concrete. This is particularly important in environments where de-icing salts are commonly used to melt ice and snow in winter, where reinforcement corrosion and loss of passivity occur more rapidly than in less demanding environments.
Residential Construction
Approved by the NHBC, fibre reinforced concrete can be used in structural toppings for Beam & Block floors, replacing traditional mesh reinforcement.
FCS can supply either Apex 60 fibres at a dosage rate of 7.5kg/m³, or Nexus 85 fibres at a class-leading dosage rate of 2.25kg/m³.
A traditional mesh option for structural toppings of this kind would be A142.
By comparison, the fibre options offer savings of 48% and 46% respectively when considering EE MJ/m².
Conclusion
As set out above, adopting fibre reinforced concrete can deliver significant reductions to the environmental impact of construction across many applications – with no extra cost, and often cost savings too.
If environmental impact is a concern – and it should be – contact FCS to discuss how we can help achieve lower EE/CO₂ and cost savings on your projects.
Reference
- Hammond, G. and Jones, C. Inventory of Carbon & Energy (ICE). Version 1.6a, University of Bath, 2008.
