I live in an area where sewage backup is likely to occur. My ground floor toilet needs one but the outlet is vertically into a concrete floor. So I need to fit one just outside where the clay pipe travels under the lawn before the first shared manhole.
I see on Amazon this product https://www.amazon.co.uk/110mm-Backflow-Valve-Non-Return/dp/B00BWNXV00/ref=sr_1_3?crid=VMJDRRGUB4AV&keywords=sewage+backflow&qid=1642535292&s=diy&sprefix=sewage+backflow%2Cdiy%2C54&sr=1-3.
Will I be able to fit this into a clay pipe which is fixed into the soil (unmoveable)? I see there is a slight difference in height of the in and out ports. Advice appreciated as to method etc. Thanks.