I am in the planning stages of remodeling the upstairs master bath. The scope will involve tearing out the existing tub and replacing it with a tiled shower, installing new flooring, and moving the toilet to another location. That is the part that concerns me. The toilet will need to be moved approximately 10 feet and I don't know if it is possible to still have sufficient slope to the drain line. The existing toilet location is against an outside wall so I assume the drain line goes down that wall. The new location is not against a wall, and as I mentioned it will be about 10 feet away. Would you have to notch out the floor joists to run the drain, or bore holes through them or what?

To add 10' to the length of a drain would require a 2.5" addtional slope if you use a 3" toilet drain pipe, 25" for a 4" pipe. Since the connection in the wall isn't moving you need to raise the toilet end of that pipe 2.5". I have no idea if that is possible without seeing the current depth of the pipe in the existing floor. I think you chances are not great but don't really have enough info.

You are stating the toilet will not be against the wall in its new location. Is that correct ?

Yes, that is correct. The new location will no longer be against the wall.

So the toilet will be standing in the middle of the room? I am trying to figure out how you you will run new vent, possibly drain. Can you post drawing /photo ?

I attempted to attach a sketch - I'm not sure it worked, but it is worth a try... Mike

OK Mike, got the sketch and assume you are moving the toilet over to the closet area, right? Bottom line, you still need 2.5 more inches of slope to run across the bathroom. Either the toilet end is rasied or the stack end is lowered, maybe a combo of both. You have to rip up most of the floor anyway so go ahead at the toilet area to see if you can lower the connection for the toilet.

You can run your new waste line:
1. behind and through the wall behind the toilet
2. in the wall on side of the toilet
3. across the bath, on opposite wall
Also
4. drill across bath, connect with existing drain

The option #4 is the last one I would look at. It is simply too far away for you to drill and maintain slope at the same time. Moreover, existing toilet drain is set high to begin with so reconecting could mean more mess. Also, you are not saying what size floor joists you have. Please, investigate and repost this important information.

See how your upstairs walls line up with downstairs walls. Some of them should be on top of each other. Concentrate on the linen closet area. If you have another closet bellow, you could even run new vertical pipe along side of the wall and box it off.

I have a suggestion that will give you a 32x60 tiled shower and you can keep the toilet where it is located. Install a Swanstone SR 3260 L retro shower pan in place of the existing tub, its made to fit in a tub's foot print. Swanstone Products

Ballengerb1: this is a great product ! Kohler makes one too. Sorry, could not to rate your answer. So, back to "...spreading more reputation..." :-D