Connecting PVC to ABS and Fernco for an adapter

[Tintin]

I'm trying to connect a PVC bathroom sink trap to ABS drain pipe in the wall. The PVC is 1 1/4" and the drain is 1 1/2". So, I have a couple of questions--can I make this connection with a Fernco and do they have a transition size adapter or because it's flexible would 1 1/2" work and I could just tighten down on the smaller pipe more? And is it to code to make this transition with the Fernco or do the connections have to be glued? It seems like cementing them together is possibly against code? I live in Oregon. Thank you!

 

[FullySprinklered]

With slip-joint fittings you can change over from 1 1/4 to 1 1/2 by using a slip-joint ferrule . It's an oversized washer that fits down in the 1.5 which will tighten down on the 1.25 lavatory drain. Forget the glue; take advantage of the slip-joint fittings. You can use it on any of the fittings right down to the trap adapter going into the wall. I use a 1.5 p-trap and do the changeover there or in an extension tube coming down. You could use a 1.25 trap and run the drain into the 1.5 trap adapter using the aforementioned ferrule.
Is this clear, or do I need to quit drinking?

 

[Sponsor]

 

[hj]

It is clear if he ALREADY knows what you are talking about, as I do, but probably not to someone who thinks a Fernco is the only option.

 

[Jadnashua]

You can put one of these on the stub at the wall, and run your tubular drain line into it...

 

[Tintin]

With slip-joint fittings you can change over from 1 1/4 to 1 1/2 by using a slip-joint ferrule . It's an oversized washer that fits down in the 1.5 which will tighten down on the 1.25 lavatory drain. Forget the glue; take advantage of the slip-joint fittings. You can use it on any of the fittings right down to the trap adapter going into the wall. I use a 1.5 p-trap and do the changeover there or in an extension tube coming down. You could use a 1.25 trap and run the drain into the 1.5 trap adapter using the aforementioned ferrule.
Is this clear, or do I need to quit drinking?

Oh yes, I was looking at pipes with the SJ connection, thank you that's great. So, if I want both sides to be slip joint I should look for a SJ piece that is 1.5 on one side and 1.25 on the other, or you are saying that the 1.5 on both sides will actually work with the 1.25 pipe as well? It would be great to have no glue, so I'm trying to avoid getting the connector that Jadnashua posted here, if I can. I just want to make sure that code is cool with all pipes being connected whether abs or pvc by slip joint--meaning I can connect right to stubbed out abs from the wall with the pvc slip joint? And lastly, stuff might not line up perfectly, so I can get a flexible p trap and that should be fine too? Thank you very much!

 

[Tintin]

Oh and I don't think I can use the connection even if I was gluing with the one above--I'd have to find an abs version of that correct, since the stub is abs? I don't think code allows you to glue abs to pvc even with the transition glue that is made for that purpose?

 

[Jadnashua]

The fitting I posted would glue to your PVC, 1.5" stub, then you can use any tubular pipe at 1.25" into it to make the connection. IT doesn't matter if it is abs, pvc, or chromed brass...it will make a compression seal with the 1.25" tubular pipe.

 

[Tintin]

The fitting I posted would glue to your PVC, 1.5" stub, then you can use any tubular pipe at 1.25" into it to make the connection. IT doesn't matter if it is abs, pvc, or chromed brass...it will make a compression seal with the 1.25" tubular pipe.

It would be great to not glue it to the stub at all and use a slip joint on there if that's possible--the stub is abs, so if I have to glue it, I'll have to get an abs version, so I'm not gluing the abs stub to the PVC fitting you posted.

Do they make SJ on both sides?

 

[Tintin]

And that's why I wondering if I can just use a fernco and that would solve all the issues

 

[Jadnashua]

So, just buy one made in abs...Home Depot sells both of them, and it's only $1.77. I've not seen a fitting made by Fernco that would do what you want. Each side needs to be properly sized for the material at hand, and you cannot just tighten the clamps to make it smaller to compensate for the differences. WIth that adapter at the wall, you could use abs, pvc, or chrome plated brass fittings...it doesn't care. What's important is to glue the proper one (type) to the existing pipe at the wall.

 

[Tintin]

Gotcha, yes, thank you. They do make a Fernco for this exact purpose that are at HD as well that's 1.5 to 1.25. I just wanted to know if there's any reason not to use it?

 

[Kreemoweet]

The reason not to use it is because it's shoddy practice. If a purpose-made fitting is readily available,
and cheaply, it is best to use it. Fernco's typically have sloppy fits, and they are not "standard" fittings
used in the trade. They are not code-approved devices. By far their largest use is by ignorant DIY'ers,
and the big-box stores sell 'em by the ton.

 

[Cacher_Chick]

Clamped flex couplings are generally used in temporary installations or for piping which will be buried, as then the backfill is supporting the pipes and joint. The proper fitting installed will support and secure the piping when it gets banged around in a cabinet base or in an exposed installation.

"Fernco" is a brand which manufactures and sells many different products, so using the name generically is not helping anyone.

 

[Tintin]

Gotcha, yes, I am aware that Mission and other companies make the flex couplings, but it seems like Fernco is the Kleenex of those--I apologize in using it generically. I most likely will go with the SJ glued fitting, but I might need some flex at some point in connecting the pipes (not necessarily on this particular use), and was told they are code approved for drains and vents above ground as well. Does this vary by state?

 

[Jadnashua]

Above ground, the fittings need to be metal reinforced so that it can keep the ends aligned. When used underground, proper backfilling should keep the two pipes aligned. Whomever told you it was approved, I'd ask them to show you the code reference...I don't think you'll find one, anywhere in the USA. I do not know of one designed as a reducer that is metal reinforced for use in this manner. There are some that are designed for converting from say copper to cast iron that have differences in diameter, but not for drainage to tubular. I could have missed it.

You usually have a lot of flexibility with tubular fittings (that can slide in and out of their mating device), and the swing of the trap to get things to align without relying on a flexible coupling. ANd, the proper fitting is probably 1/3'd the cost of the improper one you're considering using.

 

[Tintin]

Thank you, that makes sense, I really appreciate the information. I won't use the flex coupling here, but I have a vent pipe that I will need it on, so I'll make sure to use the metal reinforced one.

 

[Reach4]

I won't use the flex coupling here, but I have a vent pipe that I will need it on, so I'll make sure to use the metal reinforced one.

As a plumbing rule infractions go, that gray Fernco is about as minor as they come, and easy to change out if somebody in authority complains. Functionally, it will probably work quite well.

That is not nearly as bad as the accordion-like drain pieces you see people use at times.