This message addresses the hazard of overloading the steel decking during concreting operations.  Impact loads during construction can also overload the decking. It is important that the outlet pipe delivering the concrete is moved frequently and carefully so that heaping of the concrete is minimised. Two operatives may be needed to shovel away excess concrete.  The outlet pipe should always be manned and should not be lifted higher than knee height above the deck when discharging concrete.

Control on finished depth of the slab is also important as each 10 mm of concrete can add 0.25 kN/m2 to the slab weight; an extra 20 mm over the slab depth can result in overloading.  The deck may also deflect excessively resulting in extra weight of concrete due to ‘ponding’.  The designer should have taken this into account.

Further information:

Metal Cladding and Roofing Manufacturers Association (www.mcrma.co.uk).

BCSA Code of practice for metal decking and stud welding, 2004.

This message can be stuck onto bundles of steel decking at the factory.

Messages should be printed on A5 size laminated synthetic labels with a permanent adhesive backing to ensure adequate adhesion to the steel.

This message has been approved for use by the Metal Cladding and Roofing Manufacturers Association.