is it okay to have coupling on shower drain the trap arm?

[bronzefury]

Hi,

I'm going to use a schluter system to build my new shower. It requires that the shower drain be perfectly level and plumb.

Unfortunately, it isn't plumb and level and it isn’t directly in the center of the shower pan. The snapshot shows how far off the riser is from level.

In order to fix this issue, I plan to attach a new ptrap and riser. I’ll have to cut the trap arm to the appropriate length, add coupling, then attach abs pipe, followed by attaching the ptrap and riser and ensure the riser is level, plumb, and in the right position in the shower pan. The riser input will connect to either a schluter drain or flofx drain.

My question is, if I go with this option, is it okay to have coupling on the trap arm? If not, how else can I do it?

Thanks,

Raul

 

[Reach4]

You can have a coupling. I don't know if an unshielded or shielded type would be appropriate. If buried, unshielded. I don't know what constitutes buried in this case.

 

[Sponsor]

 

[wwhitney]

You can have a coupling. I don't know if an unshielded or shielded type would be appropriate. If buried, unshielded. I don't know what constitutes buried in this case.

That would be "underground" where you use an unshielded rubber coupling. But the picture is clearly not underground, so that would be a shielded rubber coupling.

But the OP may be able to do what they need with an ABS solvent weld coupling, rather than a rubber coupling. The rubber coupling would provide more adjustability if necessary.

Cheers, Wayne

 

[Reach4]

hat would be "underground" where you use an unshielded rubber coupling. But the picture is clearly not underground, so that would be a shielded rubber coupling.

... unless he fills the space with sand before placing the shower base.

 

[wwhitney]

... unless he fills the space with sand before placing the shower base.

Looks like another floor or crawl space below, so that doesn't track.

Cheers, Wayne

 

[bronzefury]

Hi,

Thanks for the replies. The photos are from the 2nd floor, below subfloor. By "ok" means it should be compliant to building code, right?

I was going to use 2 inch ABS coupling like this one. I bought one from Home Depot and another from Lowe's. Looks like the Lowe's version has a thicker internal stop compared to the Home Depot version.

Lowe's 2 inch, 2 foot ABS pipe was way more expensive, almost 2x the price compared to Home Depot. I measured internal diameter, external diameter, and weighed both, checked the fit to coupling and p-trap and they seem identical. Lowe's was Charlotte Pipe, HD was didn't have a clear name printed.

Regards,
bronzefury

 

[wwhitney]

I was going to use 2 inch ABS coupling like this one.

You can put an ABS coupling like that anywhere along any run of 2" ABS pipe. Well, you need to have enough pipe to hit the bottom of the socket on both sides.

Cheers, Wayne

 

[bronzefury]

Thanks Wayne.

The reason I asked is, maybe the question seemed so basic, but all Trap Arm photos I saw on the internet didn't have coupling on them.

 

[Reach4]

I was going to use 2 inch ABS coupling like this one. I bought one from Home Depot and another from Lowe's. Looks like the Lowe's version has a thicker internal stop compared to the Home Depot version.

I suggest not using a glued coupling. With glued, you have to get it right the first time. With a shielede coupling, you can make adjustments.

https://www.lowes.com/pd/Fernco-2-in-x-2-in-x-2-28-in-dia-Shielded-Specialty-Coupling-PVC-Fitting/1000075337

 

[bronzefury]

Hi Reach4,

If I used shielded coupling then the trap arm wouldn't have solid support on the Trap Arm.

I think what will work is that if I dry fit and mark between pipes to ensure each component is in the correct position before gluing. Plus, taking into account that when ABS solvent is there, the pipes will probably go into each connection deeper.

Regards,
bronzefury

 

[Reach4]

You cannot dry fit plastic pipe. The sockets are tapered, and the pipes don't seat until there is glue.

You could taper some pipes to dry fit for measurement only, and then cut un-tapered pipes to match.

Video is for shower base in concrete

However the technique could be used in other cases I think.

clever position marking.

Shielded couplings offer significant support I think.

 

[wwhitney]

You could taper some pipes to dry fit for measurement only, and then cut un-tapered pipes to match.

If you're going to cut two pieces of pipe for each final segment in the installation, you can just cut your initial pieces for the dry fit a little short. Then once you're happy with the geometry, cut your final pieces to length based on the exposed pipe length between hubs, plus two hub depths.

Cheers, Wayne

 

[bronzefury]

If, for whatever reason, I needed to use a drain snake along that pipe, I'd risk the rubber coupling being ruined then more problems, wouldn't I?

 

[Reach4]

The rubber is outside of the pipe except for a very small section. So no, you would not be risking damage by snaking.

If you want to try gluing, try it. But leave enough length on the pipe that you could cut off the glued coupling, and be able to mount a shielded coupling.

If you were experienced gluing, you could probably get it right. But without experience, it is easy to do it wrong.

 

[bronzefury]

Thanks for all the help. I finally finished it this weekend. Only took me two days!

What I got hung up on was how high I wanted the riser to be and several times dry fitting all the pieces to get it in the position I wanted. Not perfect by any stretch, but it is level and plumb.