Although the formation of saw cuts is a recognised method of controlling cracks on ground slabs, it is not recommended for upper floor slabs on metal deck for a number of reasons, including the danger of severing mesh that is critical for the composite slab fire design. From experience saw cuts do not always perform the intended function of concentrating the cracking in the location expected.

The preferred method of controlling cracking in composite slabs is through an increase in reinforcement percentage in the top of the slab. Refer to the following for more information;

• SCI AD347: Saw Cutting of Composite Slabs to Control Cracking
• SCI P300 REVISED EDITION. Composite slabs and beams using steel decking: Best practice for design and construction
• BS EN 1992-1-1 Section 7.3
• Concrete Society TR75: Composite Concrete Slabs on Steel Decking for more information
• AD150: Composite Floors – Wheel Loads from Forklift Trucks