Direct connections of ground floor WC to a drain

Direct connections of ground floor WC to a drain. A 50 mm diameter parallel branch should be used where a branch pipe would enter the stack within 200 mm below a WC connection. Smaller similar sized opposed branches not directly opposite should be offset by: 110 mm on 100 mm diameter stack; 250 mm on 150 mm diameter stack. Radius may be reduced to 200 mm for houses up to 3 storeys. A branch creates a no connection zone on a stack. No other branch may be fitted so that its centre line falls inside a zone but its centre line may be on the boundary of the zone. A branch pipe may enter the stack at the same level as a WC connection if the connections are at right angles. Maximum distances: ventilated drain 1.5 m (max); 6.0 m (max); 200 mm (min) radius bends; 800 mm (min) centre line radius; 50 mm parallel branch.