I have a large bathroom on the second story of my house. I want to convert it into 2 bathrooms. It will involve moving the existing drains. Most fixtures will be back to back in the bathrooms. Can I run one main waste pipe for the 2 showers and just tap into it for both or do I need to run separate lines for each. Same idea for the sinks and toilets.

Any suggestions for good plumbing how to books?

Thank you for any help.

In order to help we need more details. A drawing with measurement showing the stack and fixture layout, both original and proposed, would be nice. Not knowing how the drainage was installed in the original bath puts at a disadvantage. So if you can help us out with more information we will get right back to you. Regards, Tom