We are having a new WC put in. The drain for it ties into the existing drainage for the house (under a manhole on the drive).
A friend has advised that we won't need a SVP for this new WC (ground floor) as there is already one in the house serving the upstairs WC. However, the upstairs WC is on a separate drain to the new WC (the pipes meet at the manhole junction I've mentioned). My knowledge of such things is limited, but the idea doesn't stack up in my mind.
Personal experience of this set up or opinions appreciated.
A friend has advised that we won't need a SVP for this new WC (ground floor) as there is already one in the house serving the upstairs WC. However, the upstairs WC is on a separate drain to the new WC (the pipes meet at the manhole junction I've mentioned). My knowledge of such things is limited, but the idea doesn't stack up in my mind.
Personal experience of this set up or opinions appreciated.