Fire-resistant floors with LEWIS metal decking
LEWIS profiled metal decking makes it possible to realise a composite floor construction that meets fire resistance
requirements without complicated measures.
Generally, a fire resistance of 60 to 120 minutes can be realised without
a problem with all standard LEWIS floor constructions. European test reports are available. Apart from fire-resistant
floors on wooden supporting constructions, LEWIS Dovetailed sheeting is also often applied for fire-resistant floors
in lightweight steel constructions (steel framing systems).
LEWIS Dovetailed sheeting makes it easy to convert an existing wooden floor into a compartment floor. By applying a
LEWIS fire-resistant floor construction, these requirements for sound insulation of compartment floors are met at the
LEWIS sound-insulating support strips are applied on the existing t&g timber boards or directly on the wooden beams.
LEWIS profiled metal decking is applied onto the resilient strips. Peripheral connection points and conduits are
closed off with LEWIS rock wool side strips. A layer of 34 mm fine gravel concrete or liquid screed is applied onto
the LEWIS metal decking.
The total finished floor thickness applied onto the existing construction is only 65 mm (15 mm resilient strips, 16
mm sheet profile and 34 mm fine gravel concrete). The ceiling consists of 12.5 mm thick fibreglass-reinforced
plasterboard (GKF) sheeting fixed onto wooden battens or metal stud profile. With this construction, the LEWIS
composite floor has a fire resistance of = 60 minutes. When even higher requirements apply to fire resistance, these
can be met by adjusting the thickness of the ceiling finish or the fine gravel concrete.
Composite structural floor system
In addition to the best known application of LEWIS Dovetailed sheeting on (existing) wooden beam layers with a
centre-to-centre distance of 400 to 900 mm, spans with centre-to-centre distances up to 2500 mm can also be realised.
This application is mainly found in lightweight steel constructions (light gauge steel framing systems).
Depending on the span, it may sometimes be necessary to include an additional reinforcement into the LEWIS composite
floor in order to meet the 60-minute fire resistance requirement.