OK...just finished other projects... Back to plumbing... I was thinking of blocking off the hot water, but after seeing puddles under the tank (after shutting off the hot water supply) I decided the mixing valves must remain. There is also the possibility that a former owner of my house plumbed up something wrong when he put in his spa. The electrical work could have killed someone right in the tub. I tore out that spa nightmare and gutted the bathroom but maybe there is something I haven't seen yet hidden by crawl space floor insulation which is why I need to double check the pipe routing. Your right though about using one mixing valve. The hot water tank is located in a perfect position. I'll think about major changes after I install a main line water filter as I am getting tired of cleaning the brown rust every week from the bowls. It is that 4 1/2' crawl space which makes me procrastinate.

OMG! ! !! You drilled a 3/16 hole through a 2x10 Joist???? Tear the entire house down and start again. At the very least take the time & effort to fill those giant holes ! Your house is about to fall on your head!!! Be afraid. Be very afraid.

The finished floor above is all level. My concern is that the floor joist will continue to crack and get worse, this is my main concern. I am leaning towards jacking the cracked portion up so that it is in line, and then sistering two 2x7 boards, approximately 5 feet long, on each side with lag bolts. Would this provide adequate support? Is there concern with doing to much/overkill? Any thoughts would be much appreciated on this topic.

You could just put the bathroom in the basement... because that's where it's going to be if you drill 3" holes in a 6" joist... and Cyndy is right - that pipe has to slope, you can't keep it in the center of the joists. 3x6 on 24" centers isn't something that's common. Reframe it. Go below the joists. Build supports on piers on either side of the holes. Figure something else out. A photo would help a lot.