Technical Booklet C Site Preparation and Resistance to Contaminants and Moisture·Page 9·0.5
Subsoil drainage - Performance
The site and adjacent ground must be drained by subsoil drainage as far as reasonably practicable, or the building must otherwise be protected against harmful effects caused by ground water or pre-existing subsoil drainage.
It is the view of the Department that the requirements of regulation 27 will be met if the site of the building and the ground adjacent to it is drained by subsoil drainage as far as reasonably practicable, or the building is otherwise protected to prevent any harmful effect on the building or the health and safety of the occupants caused by the occurrence of ground water or any pre-existing subsoil drainage.
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