Can you use 2 inch pipe for a toilet line or are you asking for trouble I have an existing line I want to hook a toilet into that is 2inch?

Answer 1

I think the standard is a 4-5" pipe for toilet exhausts. To use a 2" pipe is asking for trouble. Friends of mine have the toilets that grind the waste in a box behind the cistern before it is flushed away. They both have had no end of trouble with the systems which grinds and flushes goes away through a standard size 22mm copper pipe to the sewer line. It is one thing to 'economise' and put up with the inconvenience of the smell and stuff like that - undoing the grind box to get to clogged blades - and there is the costs of "doing the job properly". I really advise you to do the job properly. Less hassle in the end.