Technical Booklet C Site Preparation and Resistance to Contaminants and Moisture·Page 25·5.15
Suspended concrete ground floors - construction requirements
Suspended concrete ground floors must be constructed using either 100 mm minimum in situ concrete of RC28/35 designation or precast concrete, with reinforcing steel protected by appropriate concrete cover depths.
A suspended concrete ground floor should be constructed as follows (see Diagram 5.4) – (a) in situ concrete at least 100 mm thick (but thicker if the structural design requires) of concrete designation RC28/35 to BS 8500; or (b) precast concrete with or without infilling slabs; and (c) reinforcing steel protected by nominal concrete cover of 40 mm if the concrete is in situ and at least the thickness required for exposure of Class XC3 in BS 8500 if the concrete is precast.
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