HELP!! I am new to this so please bear with me:

I am building a new house by myself... i.e. no contractors due to cost... I have three levels of bathrooms... all stacked above each other... the way I read the code I can install one stack/vent and if I stay within the "critical distance" I can drain everything into this stack/vent without vents on every fixture. I have stayed within 5' (horizontal) of the stack/vent, am using 2" PVC on all drains and the stack/vent is 4" and goes from the slab in the basement, where there is a bathroom, to the first floor which has a bath, kitchen and laundry, to the loft that has a bath only. The kitchen sink and one shower on the first floor are the only two fixtures that are further then the critical distance from the stack/vent and they will be vented with the one way vents (Duron?? Maybe is the name) . All pvc is sloped 1/4" per foot to the stack/vent.
I am being told by a plumber that I have to have a separate vent for each fixture between the trap and the stack?? HELP! I can go back in and install the vents but it was a puzzle to get the system together in the first place and I am crunched for time at this point.

If you can please fill me in I would greatly appreciate it.
Thanks

ballencd

I hope you're not going to call a final inspection if you put the job in the way you have described.  You're going to get"red tagged" if you do.  If I understand you correctly there will be one 4" stack that everything dumps into.  You only read part of the code book.   You must have missed the part that states that, "you can not discharge a major fixture past a unvented minor one." Let me call your attention to section 1413.1--- One bathroom group and 1412.3--- multistory bathroom groups in The Standard Plumbing Code Book. However you won't need separate vents for each fixture.  the fact that your bathrooms are stacked makes this easy to lay out.  Extend  the 2' vent on the lavatory in the basement past each lavatory up to the attic and tie back to the stack.  Revent each lavatory back  to the 2" vent at least 6" over the flood rim of the lavatory.  Do this for each bathroom group.  This will vent each bathroom group and keep you in code.   You are referring to Studor Mechanical Spring Loaded Vents when you call them "Duron".  Before you install them check your local codes.  Some areas outlaw Studor Vents.  You will end up with one stack and one vent revented back into the stack unless they make you run a vent on the kitchen sink and the shower.  Kudos on taking on such a big job by yourselof.  Good luck,  Tom