Adding a new toilet\shower in a detached garage
Hello, I am new to the forum and have enjoyed reading all the valuable knowledge people sharing here. I am planning to build a detached garage about 24' from the house and about 35' to the vertical drainage pipe locates in the bottom of the tri-level in which is about 5' deep from the surface. I assume to add the normal 2' to 4' below that to find the actual pipe. The vertical pipe is 4' size. My plan is to install a new toilet and shower in the garage for which should tie in with the existing drainage from the house. I plan to use the 1/4" pitch per foot formular.
My questions:
1) what material do I use from the garage to run the drainage system?
2) Can the new shower pipe share with the toilet one?
3) What do I need to use to connect to the one from the house?
4) Does a plumber just cut a hole to the cast iron pipe from the house and insert a new one for the connection?
Thanks in advance,