210mm Deep Rib Composite Floor Deck 1.25mm Galvanized Steel 6m Unpropped Span

A deep rib, long span composite floor deck rolled from 1.25mm S350GD+Z275 galvanized steel with 350 N/mm2 minimum yield strength. Engineered for 6.0m unpropped span and 9.0m propped span, this steel floor deck reduces temporary propping, cuts concrete and steel consumption and shortens construction cycles on multi storey buildings, industrial floors and bridge construction projects.

This 210mm deep trapezoidal composite floor deck is a high performance galvanized steel decking solution designed for long span composite slab construction. The profile is cold formed from 1.25mm S350GD+Z275 high tensile galvanized steel to BS EN 10346, delivering 350 N/mm2 minimum yield strength together with a Z275 zinc coating for corrosion resistance in indoor and semi exposed environments.

The deep rib geometry incorporates both cross stiffeners and longitudinal stiffeners, which raise the structural efficiency of the composite floor deck and allow 6.0m unpropped span and up to 9.0m propped span. Longer spans mean fewer temporary supports on site, faster deck laying and lower labour expenditure, while the reduced rib volume lowers concrete consumption and main steel weight compared with conventional floor decking profiles.

The 210mm rib depth combined with dual stiffener construction is the core reason this composite floor deck achieves 6.0m unpropped span and 9.0m propped span. For structural engineers specifying a long span steel floor deck, the profile delivers three measurable effects on the composite slab design: fewer temporary props per bay which reduces propping material, crane time and site labour; lower concrete volume and lighter main steel weight which reduces foundation load and overall frame cost; and a faster floor cycle because deck laying, mesh fixing and concrete pouring can proceed bay by bay without waiting for prop removal.

Long span steel floor deck laid in position ahead of reinforcement and concrete

Adjustable slab depth from 260mm to 400mm allows the same galvanized steel deck profile to serve both light loaded office floors and heavily loaded industrial floors, so one floor decking system covers multiple project packages.

This steel floor deck is designed and tested in full compliance with Eurocode 4, covering cold formed steel, composite structure and fire resistance criteria, together with BS 5950 specifications. Construction stage performance, service load behaviour and fire performance are verified through industry standard analysis, giving the composite floor deck dual international standard recognition. Repeated certification work is eliminated, so the floor decking package can be adopted in Europe, the United Kingdom, the Middle East and Asia without redesign.

BES 6001: rated Very Good for full chain responsible sourcing of raw materials and manufacturing processes, valid for BREEAM and LEED green building credits and for public infrastructure sustainability requirements.

EPD: a third party verified Environmental Product Declaration under ISO 14025 and EN 15804 records embodied carbon and environmental impact data for this composite floor deck. A valid EPD is increasingly compulsory for landmark infrastructure tenders and international green building submissions.

With an optimised rib structure and reinforcement layout, the deck delivers 2 hour soffit fire resistance without additional fireproof coating, fully compliant with code requirements for commercial, educational and medical buildings. With encastre beam connections the system achieves 60 minute fire protection, and anti crack mesh designed to BS 5950 and Eurocode 4 keeps the composite slab stable under fire conditions.

Bare soffit finish, 2 hour fire resistance without fireproof coating

In a slim floor system, the deck is installed on the bottom flange of asymmetric beams so the slab sits within the beam depth. This reduces total building height, can add an extra floor on buildings of ten storeys or more, cuts exterior cladding area and conceals mechanical services inside the slab ribs to save indoor vertical space.

• Multi storey commercial and office buildings using long span composite floor deck
• Industrial floors and warehouses with heavy imposed loads
• Bridge construction and bridge deck formwork projects
• Educational, medical and institutional buildings requiring 2 hour fire rated floors
• Slim floor and shallow floor construction where building height is critical
• Green building projects pursuing BREEAM or LEED credits with EPD evidence

Application, floor decking for multi storey buildings and bridge construction

The nestable trapezoidal shape raises the loading quantity per bundle and per container, lowering sea freight cost per square metre of floor deck. On site two workers can lay over 400 m2 of galvanized steel decking per day, and hoisting plus concrete pouring proceed rapidly, accelerating overall project progress.

Hangzhou FAMOUS Steel Engineering Co., Ltd. (FASECbuildings) supplies composite floor deck, galvanized steel decking and long span floor deck systems for global construction projects, and provides professional parameter verification, span calculation, quotation service and full technical support for structural engineers and contractors.

Note: span, slab depth and fire resistance values refer to verified project conditions. Final composite slab design should be confirmed against project loads, beam spacing and applicable local codes.