Technical Booklet N Drainage·Page 16·2.13
Ventilation stacks - general requirements
Ventilation stacks must provide ventilation to branch ventilation pipes and may ventilate underground foul drainage. The lower end may connect to a ventilated discharge stack below the lowest branch pipe connection.
A ventilation stack should provide ventilation to branch ventilation pipes and may also provide ventilation to underground foul drainage (see paragraph 3.5). The lower end of a ventilation stack may be connected to a ventilated discharge stack below the lowest branch pipe connection.
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