I renovate my house and I just redo my installation drain valve and sewage by a company and 2 points worry me: 1_ the US and EV are connected on the same pipe 100 to the whole in the sewer. Did not it need 2 different pipes EU and EV? 2_ There is no pipe for venting the vent pipe as I have seen on some drawings. Is this necessary and what is it for?
In the absence of separating networks, it is normal for the two pipes to join the collector. The venting is normally done through the primary ventilation of the descent of the WC, with exit on the roof.
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