What is the best practice for doing in-ground drain line plumbing, when dealing with a slab-on-grade bathroom with tubshower?
I’ve had plumbing subs do it for me, but haven’t paid attention, other than to notice the noise from a rotary hammer with chisel, busting out the area to make fixes or enlarge the box opening, or something.
Replies
put the plumbing in before you pour the slab
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“Ilsa, I’m no good at being noble, but it doesn’t take much to see that the problems of three little people don’t amount to a hill of beans in this crazy world”.
Gene,
New slab and plumbing?
Run the plumbing to the drain location, graded to drain trap, vent etc. installed as usual .
Now build a box about 12" sq. around the trap location , set the top of the box to finish slab grade, fill the box with either sand or gravel to the top .
Pour your slab, don't worry about some mud getting into the box, it will break right out.
After your slab is cured and you are ready to install the tub dig out the gravel, remove the box form and finish setting the tub in the usual manner.
"Poor is not the person who has too little, but the person who craves more."...Seneca
Edited 5/6/2007 11:47 pm by dovetail97128
"Now build a box...remove the box form..."
I invert a 5 gallon mud bucket, cut a hole for the drain line, set it at pour height, and after the slab has cured cut the bottom out and make necessary adjustments before filling. The advantage is that the bucket stays in and allows for future accessibility if necessary.
sawduster,
That one I will file in the memory banks. Thanks!
"Poor is not the person who has too little, but the person who craves more."...Seneca
Dovetail 97128 offers excellent tips. If you are in N.C. just make sure the waste and vent lines for the tub/shower and or lav drains are a minimum of 2" under slab. Showers are usually not an issue but the lav. and tub waste lines need to be increased.
Is that a local building code, or something in the IRC or the IPC.
UPC requires 2" waste on tub after the vent connection, & 1.5" on lav ( after vent) but does not differ if it is above ground or below.
& to Gene , Dovetail is correct about using a 12 x12 buck out. Last thing you want to do is chip out concrete cause the shoe won't fit.
If you assemble the waste & overflow on the tub first you can measure where exactly you need the trap to be.
Brass slip joint waste & overflows need an access door, Watco¯ ABS, or PVC waste & overflows do not need future access, neither do the external trip wire style waste & overflows.I fear no man & only one GOD. Me
I don't mean to wear this out, and forgive me if you have already answered this, but take a look at this pic, which shows the underslab drains for a tubshower D with an adjacent closet for an upright washer-dryer combo unit. The closet has a washerbox to the right of D.
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I'm in NY, which has adopted the IRC.
What is proposed is a 2" leg coming off the main, picking up the tubshower's 1-1/2 trapleg as shown, with the tubshower drain flat vented over to the washerbox stack.
If it ain't legit, what should be done instead?
Like I said I'm not real up on the IRC which allows flat wet venting, & the UPC does not.
In my jurisdiction we would run a vent in a "wye" configuration back to the wall shown adjacent to the tub, & tie the washer box vent & the tub vent together 6" above the flood level of the highest fixture , which in this case would be the washer box.
Shacko might be under the IRC in his jurisdiction & could probably shed more light on the subject than I.I fear no man & only one GOD. Me
Do you mean you would wye off backward, downstream of the tubshower's ptrap, so as to be aiming the wye (and the vent) in the direction of the valve wall?
Yes & no, you could also "wye" the tub drain in the direction of flow, with the branch pointed to the wall to the left towards "D".
If you put the tub's trap arm in 2" you can pull this vent anywhere within 5' of the Ptrap---- UPC, I think IRC allows a longer trap arm.I fear no man & only one GOD. Me
" neither do the external trip wire style waste & overflows."What are those.I am familar with there types of tub stops.One a stopper in the tub drain controlled by a lever on the overflow.A internal sleave blocks off the drain right under the overflow and is controlled by a lever on the overflow.A popup in the drain that is controlled from inside the tub, much like a kitchen sink stopper..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
These are pretty slick.
htView Imagetp://us.st11.yimg.com/us.st.yimg.com/I/irawoodinc_1948_25887435I fear no man & only one GOD. Me
We've got one of those Swiss things in our asian style soaking tub (American Reinforced Plastics, Tacoma, WA).
ARP is becoming quite a company, I have dealt with them on several fast tracked ADA showers.I fear no man & only one GOD. Me
2" diameter pipe under ground is a North Carolina amendment to the IPC.
Gene,
Just wanted to add a tip to my post about the box in the slab for the drain.
2" XEPS Ridgid foam works great to make the box , especially if you fill the box with sand or pea gravel.
Easy To remove when the time comes.