Same reason that the head (end) of the run i.e. to allow air in & the foul smells out.
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Yes I know & you did not need to put it back there but could have moved it up to the end (head) of the run where the new WC is now.Middle? Where the vent is now is where the original vent was, so I just put a tee in and added another wc.
At the end of the branch to the toilet I think he means Danny. How's your new lawn doing? Did it survive the drought
Reply to the thread, titled "Connecting to cast iron soil stacks??" which is posted in Boiler Advice Forum on Plumbers Forums.
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