Technical Booklet C Site Preparation and Resistance to Contaminants and Moisture·Page 20·4.4
Ground water affecting ground stability and properties
Where ground water beneath or around the building could adversely affect the stability and properties of the ground, gravity drainage or other effective safeguards must be provided.
4.4 Where there is a risk that ground water beneath or around the building could adversely affect the stability and properties of the ground, either the ground to be covered by the building should be drained by gravity, or some other effective means should be taken to safeguard the building (see Section 5 – Floors).
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