I'm updating our master bathroom and I have some questions about the drain pipe and vent. I removed the one piece fiberglass bath/shower and it had 1 1/2" copper drain pipe. It leads to a sanitary tee that goes to a horizontal vent and to a 3" toilet drain pipe.
First question: All the pipes are copper, I wanted to cut out the 1 1/2" shower drain and sanitary tee and replace that section with PVC and make all of it 2" (eliminating the 1 1/2" completely). I will have to connect the PVC with a plastic to copper fernco coupling. Is this ok?
second question: The sanitary tee swoops from the horizontal vent to the toilet drain (against the flow of the shower drain). I thought I read on here somewhere that sanitary tee's are only for vertical stacks? If not, and I use an ST, then how should I position it, currently it seems backwards, shouldn't it flow with where the water goes? -From the shower to the toilet drain (not the horizontal vent).
third question: The current 2" vent runs horizontally off the sanitary tee about 2' then 90's up to the attic. I know I have to vent each fixture, I was going to run a new vent about 6" from the shower drain trap and run it strait up into the attic. Can I tie into the same 2" vent? Also, I only wanted to use a 1" pipe due to limited space, is this acceptable?
I've attached a pic. Any help would be appreciated. Thanks.
First question: All the pipes are copper, I wanted to cut out the 1 1/2" shower drain and sanitary tee and replace that section with PVC and make all of it 2" (eliminating the 1 1/2" completely). I will have to connect the PVC with a plastic to copper fernco coupling. Is this ok?
second question: The sanitary tee swoops from the horizontal vent to the toilet drain (against the flow of the shower drain). I thought I read on here somewhere that sanitary tee's are only for vertical stacks? If not, and I use an ST, then how should I position it, currently it seems backwards, shouldn't it flow with where the water goes? -From the shower to the toilet drain (not the horizontal vent).
third question: The current 2" vent runs horizontally off the sanitary tee about 2' then 90's up to the attic. I know I have to vent each fixture, I was going to run a new vent about 6" from the shower drain trap and run it strait up into the attic. Can I tie into the same 2" vent? Also, I only wanted to use a 1" pipe due to limited space, is this acceptable?
I've attached a pic. Any help would be appreciated. Thanks.
