Understanding head of the drain with regards to stub stacks HELP PLEASE.

[heatho87]

Hi Im finding it hard to understand about the head of the drain and stub stacks if /were they can be fitted etc
Am I right in saying you can have a stub stack at the head of the drain!!!

Help please!

 

[tackleburger]

An unventilated stub stack terminated with an access fitting is a secondary stack may be used to connect a group of ground floor appliances to the ventilated building drain provided the vertical drop to the invert level of the drain does not exceed 1.5m from a WC and 2.5m from a waste appliance. If you have more than one stub stack the head of the arrangement has to be vented to atmosphere or AAVs added to each stub stack arrangement. I hope this helps you.

 

[fuzzy]

in short the head of the drain should be a ventilated stack, subsequent ones can be stub stacks