Recenlty read an article in "This Old House" magazine and old Tom Silva was bad mouthing plumbers and electricians for notching floor joists. I've done some plumbing, and have several books on such and all show driling holes for drains and notching floor joists. I can see how to get around notching with alot of plumbing run through the walls. But how else would you run a drain without cutting into the floor joists? Just curious as I'm getting ready to put in a new bathroom upstairs and can't figure out how to do so without running 4 drains straight down to the basement which seems silly.