Technical Booklet N Drainage·Page 6·79
Requirement to provide drainage systems
Every building must be provided with sanitary pipework, underground foul drainage and rainwater drainage as necessary for the hygienic and adequate disposal of foul water and rainwater.
Every building shall be provided with such sanitary pipework, underground foul drainage and rainwater drainage as may be necessary for the hygienic and adequate disposal of foul water and rainwater from that building.
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