How do I join ABS pipe to PVC pipe?

ben2go · Apr 28, 2013

I know I could probably "google" it,but I'd rather hear from people that have successfully done it.I am still working on the mobile home I been posting about the past few months.I just completed replacing the main sewer line to the septic tank after a back up ruined the bathroom and floor.Now I am moving onto replacing the toilet.It requires a 4inch flange which means I need to replace the plumbing stack.The plumbing stack has the sink and tub drains ran into it.The stack is ABS as is the drain lines that run into it.I am rebuilding the stack with PVC.What do I need to use to "glue" the ABS to the PVC?The Lowe's cadet looked at me as if I had ask him about him mum and dad's bedroom life. :laughing:

Thanks in advance for all the help you all give me.

daveshoot · Apr 28, 2013

Since it's not under pressure, the transition glue should do fine... Oatey 4 oz. ABS to PVC Transition Cement-309003 at The Home Depot

Whenever possible and pressure is an issue, I would glue threaded adapters with the appropriate glue for each pipe type. Probably not practical in the toilet stack (never done that).

bcp · Apr 28, 2013

1. Rebuild the stack with ABS.

2. Use a threaded connector

I've had no luck combining the two with glue. My sizes never matched for a slip fit.

Bruce

dave1949 · Apr 28, 2013

There is a glue for that. I know from experience using the wrong glue gives bad results. :laughing:

Oatey 4 oz. ABS to PVC Transition Cement-309003 at The Home Depot

DT86 · Apr 28, 2013

Some will say ABS to PVC is a no-no. But regular PVC glue will work fine for a non pressurized fitting, such as your drain.

STROIL · Apr 28, 2013

Ben:

Normal PVC glue (any of the particular formulas made for gluing PVC) will also glue ABS and will glue pvc to abs. If you research doing it however, you will read that it is not recommended, and the reason is that PVC and ABS have different thermal expansion properties (they expand and contract at different rates and at different temperatures). Theoretically, a pvc/abs joint on drain pipe could be subject to a lot of temperature swings if it were downstream of a shower or washing machine, and over time could be compromised because of the different expansion rates. That said, I know many plumbers and contractors, including myself, that have had no choice but to glue the two together in some situations, and in practical reality, I've never heard of anyone ever having a problem with a pvc/abs joint. Personally, I would say go for it and forget it. I might ad, I have no idea what an inspector might say about it, if your work will be inspected under a permit. In fact, I'm not sure any inspectors I've ever worked with would know the difference.

FredH · Apr 28, 2013

Don't know for sure , but thinking it is not possible as sizes are different . 4" pvc o.d. being different than 4" abs o.d. ???? Not saying you cannot join them , just not sure if there are connections like that .
I had something similar when One brother and I redid our parents toilet and bathroom . Had to rebuild the floor , then with new flange things were not lining up with old cast iron pipe . Ended up cutting cast iron pipe down lower and using a rubber clamp connector to seal to 2 pieces of pipe . The 4" Abs was virtually touching the 4" cast iron , end to end , but that was the only thing we could find to seal the pipes together . Two large stainless clamps on each side , thus joint will likely out live me and my brother .

Fred H.

From internet , type of clamp I referenced :

dave1949 · Apr 28, 2013

FredH said:
Don't know for sure , but thinking it is not possible as sizes are different . 4" pvc o.d. being different than 4" abs o.d. ???? Not saying you cannot join them , just not sure if there are connections like that .
I had something similar when One brother and I redid our parents toilet and bathroom . Had to rebuild the floor , then with new flange things were not lining up with old cast iron pipe . Ended up cutting cast iron pipe down lower and using a rubber clamp connector to seal to 2 pieces of pipe . The 4" Abs was virtually touching the 4" cast iron , end to end , but that was the only thing we could find to seal the pipes together . Two large stainless clamps on each side , thus joint will likely out live me and my brother .

Fred H.

The world would be a crappy place without fernco's. :laughing:

FredH · Apr 28, 2013

" The world would be a crappy place without fernco's. "

At least under Our Parents House it would of been

Fred H.

ultrarunner · Apr 29, 2013

Yes... and if you are really concerned... you can buy them with 4 hose clamps instead of two.

ben2go · Apr 29, 2013

Thanks.This is all good info.No permits are required because it's a mobile home.Even in a house here,no permits are need for replacement,only new construction.

After looking over everything again,I will eliminate one run of pipe.The washing machine drains into a gray water ditch,which is allowed here.No other drains can be attached tho.So now I only need a sanitary T which makes only one ABS to PVC connection.I have PVC glue.I don't think there will be a wide temperature swing at the junction.It carries the kitchen sink water which is 40 feet away.I've always stopped anyone from pouring water, hotter than comes from the faucet, down the sink.The stack will be all new the only connection will be the kitchen drain.The stack will be based on the T below.

If I can buy the property from my cousin,I will completely remodel and replace all the old plumbing.For now,we need this place to get us through until we finish remodeling my father's old mobile home.Hopefully we will be in there by winter.If everything goes as planned,in a couple years we hope renting the mobile homes will pay for our acreage.Then I can build my dream cabin.:cool2:

ENG18LT · Apr 29, 2013

Ok I guess I get to interject a little humor here:

Duct tape!

:thumbsup:

TomSeller · Apr 29, 2013

Put male end into female end.

/pine · Apr 29, 2013

I like using a short piece of ABS up through roof penetration vents...the black pipe looks a lot better than white PVC...
I've never had a problem with regular PVC cement but I've also used silicone on the vent stack...

I always lightly sand the mating parts...

AchingBack · Apr 29, 2013

I see no valid reason to mix the two kinds of pipe.

quicksandfarmer · Apr 29, 2013

Gluing different plastics is always a hack job. Use a hubless connector (rubber clamp).

ben2go · Apr 29, 2013

I am not redoing all the drains.Just under the toilet,because what I have won't work with the new style toilet I am installing.It calls for a 4 inch flange and the current stack is only 3 inch ABS 3"x3" 2"x2".I can only find PVC pipe here and I have already had to replace the main line to the septic tank with 4 inch PVC.Just finished that last friday.I just need to slide by till winter.I should be done with my father's old MH and I can move in and redo the one I am staying in now.

ben2go · Apr 29, 2013

quicksandfarmer said:
Gluing different plastics is always a hack job. Use a hubless connector (rubber clamp).

Good idea,if I can find one that will connect a 4"x4"x2" fitting to 2" pipe.That step in the 2" section of the sanitary Y is the problem with the rubber connector.I could splice in a piece of 2 inch PVC but then I am buying a whole 8 or 10 foot section of pipe for maybe 4 inch splice.

It is late.I may not be thinking about this correctly.I'll revisit this tomorrow.

quicksandfarmer · Apr 30, 2013

ben2go said:
Good idea,if I can find one that will connect a 4"x4"x2" fitting to 2" pipe.That step in the 2" section of the sanitary Y is the problem with the rubber connector.I could splice in a piece of 2 inch PVC but then I am buying a whole 8 or 10 foot section of pipe for maybe 4 inch splice.

It is late.I may not be thinking about this correctly.I'll revisit this tomorrow.

OK, I thought the transition was in the 4" section. For 2", they make threaded fittings.

Home Depot sells 2' sections of pipe, at least around here. Looking at the website, the fittings are about two bucks each, as is a 2' section of pipe. Six bucks to do the job right.

ben2go · Apr 30, 2013

quicksandfarmer said:
OK, I thought the transition was in the 4" section. For 2", they make threaded fittings.

Home Depot sells 2' sections of pipe, at least around here. Looking at the website, the fittings are about two bucks each, as is a 2' section of pipe. Six bucks to do the job right.

I found a hardware store that's a little outta the way, but they have everything, plus PVC by the foot.They don't have ABS pipe either.No one c there could give me a solid answer why ABS is hard to find.The best I got was code MAY NOT call for it.No certainty there.