I need to move a toilet flange about six inches. Unfortunately it needs to move on the other side of a floor joist thar it is next to. How much of the joist can I cut inorder to relocate it.

Codes vary but generally you can only remove 1/3 of a joist and it should be fairly centered. A 3" pipe through an 10" joist should be fine. When you connect back to the existing pipe will it be a butt joint or do you need to make a turn?

Thanks for the quick response... I will be moving it 90 degrees from present position so I will have to turn it through the joist inorder to join to existing pipe. (PVC)

Best to use two 45 degree bends rather than one 90 elbow.

Thank you...