Tae's master bathroom remodel

[dontnomuch]

This will be the first few of many many questions in the coming weeks and months. I have decided to embark on an adventure of remodeling our master bathroom. I am currently in the process of almost gutting our entire master bath. The surround tub, shower, cabinets, sinks, toilet, and tile. I am just about done gutting everything.

Question 1: See pic below. I want to use the drain from a previous sink for my new Kerdi shower drain. However, I am not sure how to reroute the drain and attached vent. As you can see, the drain comes up from the 3/4" subfloor and goes back into the wall. This same wall will also be used as one of the sides of my new shower. Obviously I don't want a pipe sticking out of the wall in my shower. What's the best way to reroute. Can I drill a 1.5" hole thru the 2x4 in the floor for the vent? Any other way to do this?

Question 2: I used to have dual sinks with separate supply lines and drains. I am planning to use one of the old sink drains and supply lines for the new shower. I still want to have dual sinks, but I would like to simplify things by using the same supply lines to feed both sinks, and use the same drain line for both sinks? Would there be any problems doing this?

Question 3: Is there an easy way to remove the subfloor? Where should I cut the floor? I was thinking right on top of the floor joist (of course I won't cut too deep that I cut into the joist itself), so that you can reinstall the plywood. I have 3/4" plywood on 16" center joists. I am not sure if my question makes sense on this one.

-Tae

[yvyhovsky]

Your first 2 questions not real clear might be me
# 3 is easy Take a circular saw set the depth to just cut the sub floor take a straight edge or levele and draw lines where joist are and cut out down the center. once out re frame or add cross support for new added sub floor this so the entire new added floor has support I think I have pictures from am old job. I allways added new support to match existing joist if its 2x10 0r 2x 12 then use the same liquid nail and nail it make sure its stiff before finishing the job

[yvyhovsky]

sorry for eailer response these are difficult to answere without more info
some of it seems basic but need more info
size of supply line to the sinks and shower also picture does not show very clearly venting you speak

[yvyhovsky]

1 supply and drain are the best way to go sorry for earlier respone now very clear this is the way to go

[dontnomuch]

Thanks for the responses.

For question 1, I've updated the picture with some info. My basic question is, can I drill a 1.5" hole in the 2x4 frame, so that the vent line will not stick out the wall?

[Oldrem]

Yes, just try to center it the best possible if it's a load bearing wall - won't hurt at all otherwise. You find many notched 2x4's in wall construction.

[dontnomuch]

I am getting ready to purchase Kerdi membrane, drain, band. I anticipate I will need about 100 sq.ft. of Kerdi for my shower. Is there a rule-of-thumb for determining how much kerdi-band to order?

[Brian in San Diego]

Tae,

Hold on a minute! I think you are trying to do something that isn't quite kosher. The first thing is that it has to be trapped after the drain. In the case of your sink, the trap is right under the sink. With a shower, your trap is in the floor space below the shower drain or in the slab. Second, the line has to be vented prior to entering the waste stack. If you look at your picture, you'll see that the vent comes right off the top, therefore it's vented prior to entering the waste stack. Once you get the subfloor up, maybe there will be another way, but you cannot do it the way you've described.

In regard to your original question #2, I think the drain would have to be 2" minimum branched to two 1.5"...same rules apply, the line has to be vented prior to entering the waste stack.

Brian

[dontnomuch]

Brian,

I don't think I completely explained what I was trying to do. I will be removing the existing 1.5"x1.5"x2" tee. Then, I will extend the 1.5" vent line down through the 2x4 and subfloor. This is where my question #1 came in. I would need to drill a 1.5" dia hole in the 2x4 frame in order to extend it down underneath the subfloor. Next, I would install a new 1.5"x1.5"x2" tee and a new trap (all under the subfloor) for my new shower. Hope that makes sense.

As for question #2 two, are you saying that it would be OK to split the 2" drain to two separate 1.5" drains for my sinks as long as I vent prior to entering the waste stack?

[Brian in San Diego]

Tae,

I perfectly understood what you are trying to do and code says you can't do it that way...unless you have alot of room under the subfloor. You mention a 1.5x1.5x2 tee...again a no-no for a shower installation. If you think that catching that vent is the only way your shower will work then here's how it would have to be...kerdi drain, 2' trap and a 2x2x1.5 tee with the branch pointed straight up. The branch (1.5) would then have to be reconnected to the existing vent line (with a continuous slope up from the connection). The 2" main would have to be connected to the existing 2" waste line going toward the stack. Where is the existing tub drain and vent? I'm not saying your plan cannot be accomplished, but the way you are trying to go about it violates the UPC.

Yes, you can split the 2" with a 1.5x1.5x2 sanitary tee.

Brian

[dontnomuch]

Brian,

I do have plenty of room underneath the subfloor for new trap and tee. I stand corrected, what I meant was to replace the existing 1.5"x1.5"x2" tee with a 2"x2"x1.5" tree.

[dontnomuch]

Brian,

If you were doing it to code, how would you convert the drain above in my pic to a shower drain?

[Brian in San Diego]

Tae,

I think we are having a failure to communicate! If you can meet all the codes, then your plan may work. I have doubts that you can properly slope the vent line away from your tee installed after your trap. Once you get below the subfloor with your vent what fittings are you going to use to get to the tee? Remember the vent has to slope just as though it's a drain...only in reverse.

Brian

[dontnomuch]

Brian,

I guess I am confused by what you mean by sloping the vent? Isn't it just a vertical line? See my drawing as to what I want to do.

[Brian in San Diego]

Tae,

Now THAT explains everything! I saw the 2" going into the subfloor and thought it travelled away from the wall. What I don't understand (or can't see) is why the 2" doesn't come up through the wall. The way you have diagrammed it is fine and meets all code requirements. If I had a decent software program, I'd draw what I thought you were trying to do. It's a moot point...you can do it as drawn.

Just as an aside...a tee is called out by the run and then then the branch. So what you have in your drawing is a 2x1.5x2 tee. Make sure you get a sanitary tee, not a regular tee.

I keep going back to your photograph. I'd like to see a photo once you have the subfloor out.

Brian