Adding an upstairs bathroom, double lavs in Master

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Terry

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Sometimes we get calls to retrofit plumbing in an older 80's home. Maybe the homeowener wants to change the layout, or add a second lav. On the forum we get requests for information on this, but seldom get the pictures we need to for full answer. Here's a retrofit that I was able to take pictures of.

double_lav_right_side_3.jpg


We start on one side of the room with a bare wall. It was kind of bare to start with. They had a tub and a shower along this wall draining into a 1.5" line, and vented at 8" above the floor. Not the 42" that we expect to see. There should have been a lot more pipes to see in this photo. They had notched the floor joists to install the plumbing. The first thing I did was to remove the old plumbing, and have the general slap some plywood alongside the floor joists for the repair.

double_lav_right_side_2.jpg


The plumbing had gone to the left here, down a 1.5" pipe. Too small for the previous tub and shower, and too small for a double lav with current plumbing codes. Bathroom lavs can get a lot of goo in them.
The black ABS to the right is dropping straight down a dining room wall and into the crawlspace, where it can tie into the main 3" waste line. Sometimes with a double lav, I use a double fixture cross, but since I'm dropping toward the right, this has fewer horizontal changes of direction. In plumbing, you limit the horizontal changes as much as you can. The 2" line was dropped down to the center of the floor joists, leaving at least 2" on the top and the bottom of the floor joist. The copper had been notched on the top of the floor joist before, and that was also dropped down lower. It will be impossible for someone to put a screw through those now.

double_lav_right_side_1.jpg


Here is the waste and vents before running water. There is a 2" cleanout to the right. In King County they don't require one on the upper floor like this on a lav, but it's nice.
The vent is 1.5" and run at 42", and ties into the existing 2" vent near the window and through the roof.
I like to use trap arms on my jobs, but I could have run the drains centered too. I like trap arms for the luxury of moving the center if the general or homeowner decides to shift the lav on the wall. It's a lot easier to cut or extend a horizontal trap arm that way. I run my lav drains at 20" for a 32" counter.

double_lav_right_side_5.jpg


Here it is with the water run. Notice the hosebib on the left drain, and a washing machine stop, with washer hose connecting the two. This is for testing afterwards. The electritian has run his boxes and wiring too.
Plumbing goes first for that reason. The wires can find their way around the plumbing. First rule of plumbng is "Stuff runs downhill". Wires don't have that rule.

We also nail plate before covering the walls.

nail_in_pipe.jpg


This is why you use nail plates.
I wound up removing this section of pipe totally. This was on the other side of the room.
 
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Terry

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Dropping down the dining room wall and into the crawl space.

miller_lav_2131.jpg


End of line cleanout in crawl space.

double_lav_right_side_4.jpg


Dropping into a wye on the main 3" line.

miller_double_lav2.jpg
 
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Terry

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This looked kind of messy. It was a double lav system on the corner. I don't know where two people stand if they both try to use it at the same time.
The fittings were installed crooked and barely in the fittings. I wound up rmoving most of this.

miller_kohler_shower_5.jpg


This area became a shower

miller_kohler_shower_4.jpg


Again, plywood was installed on the floor joist to repair it. The fitting for the vent is a 2.0" x 1.5" combo on it's back. That vent extends to 42" before becoming horizontal.
I went back a ways and extending 3/4" to the tee above here. Splitting the hot at that point. I used copper instead of PEX at that point for it's larger size since I'm running two heads there.
There is a tub on the left for the next room. I didn't want to share a 1/2" line for a tub and a shower with that many outputs.


miller_kohler_shower_1.jpg


A new thermostatic shower valve by Kohler, with two volume controls. The lower one for the hand shower which will have it's rail for placement. The top control is for the rain head in the ceiling.

miller_kohler_shower_6.jpg


After tile and trim.


miller_kohler_shower_3.jpg


Ceiling rain shower head.
 
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VonChuck

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Yes, thank you for showing us DIY novices how to do this. It is so nice to have pictures.

I have one question on the rough-in.
If I understand you correctly, you don't run it like this because it doesn't leave you an easy adjustment for "what-ifs".
Would running it like this be "in code"?
double_lav.jpg

The inspector that signed off on this thought it was very nice.
Terry
 
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Terry

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double_lav_rough_2.jpg


It could have been with a double fixture fittng, or I could have come run the two santees and pointed them straight out. There are quite a few ways of doing it to code.
I like trap arms because making a change is easier.
Yes............I know the builder and the architect knew what they were doing before the cabinets were ordered, but sometimes the cabinet layout is not what is shown on the plan.
 

JoshRountree

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Did you miss a nail plate?

Why copper for the stub outs? Would PEX be okay?

double_lav_right_side_5.jpg


miller_double_lav3.jpg


The left basin after the cabinet has been set.
 
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Terry

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We were still nail plating the next day. My son was in charge of that. We didn't leave the hose or hosebib on either after we were done.
PEX is fine for stubouts, but I prefer copper for my compression stops.
 

Terry

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It feels more solid. Though there is nothing wrong with using PEX for stubouts.
There are so many things in plumbing that can be done, and for different reasons. I used to work with 150 other plumbers. We tended to do things a little different.
The framers loved my layouts. I took less wood out, and so they had less to do when I was done.
I used less pipe and fittings than the others, so it was quicker to do my layouts. I don't do new construction anymore, more remodel and service.
The layout above may have looked a bit different if I had gotten to the home when it was new, and before the drywall was up. I was glad to find a spot where a single piece of pipe was able to drop through a floor and into the crawl.
It's way easier when everything is open.

The one place you can't use PEX is on a tub spout. The size reduction causes problems there. It's okay for a shower head.
 

JoshRountree

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What's your opinion on tub spouts? All sweated copper from valve, or copper to drop ear and nipple from there?

I either use all copper for the tub spout and use a slip spout, or use a drop ear and brass nipple. Either full size copper or full size nipple to prevent pushing water up to the shower head when running a bath.
Terry Love
 
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