HDPE pipe used in slab

Hi,

I'm building a workshop and my contractor used 4" HDPE pipe in my slab. Is there any solution for connecting a toilet flange to this pipe or should I bust up my slab to remove this pipe?

Thanks for the help.

What kind of HDPE? The only 4" I have seen is not smooth wall unless it was gas pipe? Can you take a picture?

damn..hdpe....what glue did he use ?


it is my understanding that hdpe and pvc CAN NOT be glued together. mechanical connection only. perhaps some of my brethren
plumbers know of a glue, i do not.

according to upc plumbiing code, hdpe is not approved as drainage pipe. pvc sch 40 under a house, or cast iron is

this is not kosher...but...what size pipe did he install ?
http://www.simplyplumbing.com/11957-closet-flange.html
you might...i said might. get away with a repair slip in flange, and hammer drill it to the floor

o\i have, in a bind, used a brass flange and lead wool to make a connection between plastic and cast iron

http://www.simplyplumbing.com/32264-closet-flange.html?gclid=CjwKEAjwm_K_BRDx5o-sxq6ouXASJAC7TsFLj2ZAYUuA_5fawIKjzeDqhm-

tx7wGzl-clKCn-5ljFRoC08Dw_wcB

i believe, Mr David or Mr phishfood has a video tutorial

http://www.simplyplumbing.com/12492-lead-wool.html

Here are a couple of pics of the pipe. It's like this, but smoothwall and no holes:

http://www.ads-pipe.com/en/product.asp?page=ads_triple_wall____smoothwall

The glue he used did not hold up. You can twist the pipe and it pops loose. He used a 4" pipe. The only thing that is holding it is the concrete. Coming up at the elbow the glue has broken loose.

frodo said:

damn..hdpe....what glue did he use ?


it is my understanding that hdpe and pvc CAN NOT be glued together. mechanical connection only. perhaps some of my brethren
plumbers know of a glue, i do not.

according to upc plumbiing code, hdpe is not approved as drainage pipe. pvc sch 40 under a house, or cast iron is

this is not kosher...but...what size pipe did he install ?
http://www.simplyplumbing.com/11957-closet-flange.html
you might...i said might. get away with a repair slip in flange, and hammer drill it to the floor

o\i have, in a bind, used a brass flange and lead wool to make a connection between plastic and cast iron

http://www.simplyplumbing.com/32264-closet-flange.html?gclid=CjwKEAjwm_K_BRDx5o-sxq6ouXASJAC7TsFLj2ZAYUuA_5fawIKjzeDqhm-

tx7wGzl-clKCn-5ljFRoC08Dw_wcB

i believe, Mr David or Mr phishfood has a video tutorial

http://www.simplyplumbing.com/12492-lead-wool.html

Click to expand...

I know it probably not code or anything but what about an epoxy to bond the two materials? Or a 3" toilet flange that slips inside? I only mention because it is a workshop and not a home.

i think if it is 4'' and you slip a collar inside. with out glueing it it would work, wont leak, as long as the sewer does not back up

back in the old days..i have found toilets sitting on just a pipe, no flange, bolted to the floor

it is all about the wax seal


in that picture, i see a couple of problems
yeah ok..we can work around the collar.


but, i do not see fall on that pipe or a vent...come on !!!

fall is a must. the crap will not go away with out gravity, i do not care how long you wish it

and it needs a vent.

try this. put a strw in a glass of water, put your finger over the end of the straw...pik the straw up
nothing comes out NO VENT, take your finger off the end VENT

I'll have to check into the epoxy and the slip in flange - good ideas!

The picture is a little deceiving. The pipe you see coming up will be going to the septic tank. It just has an up spout to remind me where the pipe is . At the far end is two pipes, one for the toilet and one for the sink/vent.

Thanks for the help!

That triple wall ADS is okay for outside septic drainage, but not for interior work. ADS fittings need to be used which are a a push/snap-in connection, since no solvent bonding is used at all on that pipe. It's not approved for building drains to public sewers or interior work. They will leak and an epoxy will probably leak as well as any glue. The outside layer will peel loose with bonding agents just as you've already seen.

Is the contractor willing to cut out the concrete, replace the pipe and dowel in new rebar and repour? Sounds like a lot of work but really is not to bad for a guy who does that kind of work.

Or saw cut and bring the sewer out the other side and run around the building if you have enough fall, that would lesson the sawcutting and repour.

what you need is a plumber,

that pipe is illegal, the installation is illegal\

the pipe is supposed to be under the vapor barrier and bedded in the dirt

the whole thing from start to finish is a f---up mess,

If it leaks you will have a swimming pool of poo with that plastic. Gonna be a stinky shop.

Thanks Chris, frodo and Caduceus for your input - very valuable. I think I'm going plug up the pipes and cement over them and not have a restroom in the shop. It's only a few feet to the house anyway.

Thanks again!

Can you sawcut a square and dig under the footing and then run new pipe outside the building? It won't be hard and then you have piping you never have to worry about. You can vent it on an interior wall or outside the building, not hard at all with a chipping gun or jackhammer.

Likely you won't have a problem with the existing pipe encased in concrete but if you did it would be stinky. We generally like to advise you on the proper way to do things.

6stringer said:

I'll have to check into the epoxy and the slip in flange - good ideas!

The picture is a little deceiving. The pipe you see coming up will be going to the septic tank. It just has an up spout to remind me where the pipe is . At the far end is two pipes, one for the toilet and one for the sink/vent.

Thanks for the help!

Click to expand...

Why did he not use pvc?

Thanks Chris. I'm thinking that would be the way to go.

Hi Sheplumber. As for why he didn't use PVC, he said the store was sold out and said he he could use the HDPE pipe instead. I think he was being cheap and wanted to pocket in profits. I let him go and looking for someone to do the job right. I'll take my losses now before it really turns into a nightmare.

6stringer said:

Thanks Chris. I'm thinking that would be the way to go.

Hi Sheplumber. As for why he didn't use PVC, he said the store was sold out and said he he could use the HDPE pipe instead. I think he was being cheap and wanted to pocket in profits. I let him go and looking for someone to do the job right. I'll take my losses now before it really turns into a nightmare.

Click to expand...

At the local big box store 4" SCH 40 PVC is $20 per 10 ft. and the triple wall ADS is $8 per 10 ft. You might be right.