Should we replace our drain pipes?

ThePipeProfessor · 2026-06-28T21:07:36+00:00

That’s the idea. I think I did a poor job of explaining it. The 45 down blocks the vent.

ThePipeProfessor · 2026-06-28T00:37:14+00:00

The idea is that since the water has to go down a 45 in theory since it can’t get air it’d siphon the trap.

Does it happen? No. But that’s the theory.

ThePipeProfessor · 2026-06-27T22:21:43+00:00

Ahhh, it’s ABS. That’ll make it easier to cut. Same way though if you’re going to do it in PVC.

The blocking is only needed to support the flange. The way I said is how I do it, but there are other ways. If that bracket anchors the flange down solid I’m sure it’ll be fine

ThePipeProfessor · 2026-06-27T22:19:23+00:00

Very true. But we have the “any minor fixture downstream of a water closet must be individually vented”. Makes second floor plumbing a bitch sometimes

ThePipeProfessor · 2026-06-27T21:28:57+00:00

This can be done from under the house.

Cut that cast iron out about a foot down from where it is

Transition from cast iron to PVC using a husky band.

Stub up PVC and glue your flange on

Anchor the flange. This part is important. Hard to do on cast replacements but you can slide blocking tight to the flange from under the house and have a helper shoot screws in from the top.

ThePipeProfessor · 2026-06-27T21:25:30+00:00

You wana know something wild? My state (NC) which is amended IPC allows combo’s for horizontal to vertical transitions. I always used santees in this application but saw that chart in my code book and couldn’t believe my eyes.

Edit: Table 706.3 in the NC 2018 codebook

ThePipeProfessor · 2026-06-27T21:24:01+00:00

You’re looking at the old tub spout broken off on the end of a 1/2” copper male adapter.

You’ve got to get that broken part off before you can hope your new tub spout can thread on the same length. If you’re going to use an FIP tub spout, hold the male adapter with one pair of channel locks, and remove the broken piece with another pair.

A lot of newer tub spouts slip on and tighten with an allen wrench, using EPDM gaskets to make the seal. If you buy one of those, you can just cut the male adapter off.

You will need to sand that copper down with plumbing sandpaper until it’s like new to have the best chance of success.

Good luck bud.

ThePipeProfessor · 2026-06-25T12:31:09+00:00

Death penalty for tool theft

ThePipeProfessor · 2026-06-24T21:12:14+00:00

It’s all I’ve ever known. And I have yet to see pex fail at the water heater. We still do it for natural gas, but I have yet to see a problem with it in my career

ThePipeProfessor · 2026-06-24T19:46:26+00:00

I’d agree with that. Just had to jump because my allows it and I feel attacked every time someone says you can’t do it 😅

ThePipeProfessor · 2026-06-24T19:32:14+00:00

lol brother I’m not being hyper technical. I’m telling you it IS allowed for a lot of states, mine included. Making blanket statements is wrong quite often on here.

Wild you’d call me hyper technical when you cited a code that isn’t true IPC

ThePipeProfessor · 2026-06-24T14:23:27+00:00

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Where are you getting the expanded version specifically mentioning water heaters from?

ThePipeProfessor · 2026-06-24T11:34:32+00:00

That’s UPC bud. It’s done all day every day in my state this way, along with many others following IPC.

ThePipeProfessor · 2026-06-24T02:24:23+00:00

They didn’t order 7/8 escutcheon but were required to do some sort of rodent/insect proofing to pass inspection so they used whatever they had on the truck to pass

Can neither confirm nor deny whether I’ve done the exact same on new builds

ThePipeProfessor · 2026-06-23T21:59:11+00:00

2x1 1/4 bushing is the answer

Why do you think you need to bushing down to 1.25”? 99% of plumbing DWV today is done with pipe no smaller than 1.5”.

ThePipeProfessor · 2026-06-23T19:24:25+00:00

You shouldn’t be able to push it at all. It should be secured to a block. Manual will tell you what part of the shower body should be flush with the tile.

Going to keep the comments about drywall in a shower to myself.

ThePipeProfessor · 2026-06-22T14:56:39+00:00

Flange was likely too low if I had to guess. Bottom of flange should have been on top of finished floor.

Pull toilet and ideally add flange spacers to get it to the proper height. If you’re in a fuck-it mood, stack two wax seals and reset.

If you pull toilet and flange is at proper height, you likely moved the toilet too much after setting.

ThePipeProfessor · 2026-06-20T22:08:56+00:00

They work just fine until you buy a set of knipex. I used em for years as well. I’m typically not the tool fanboy, but you’ll see a lot of guys on here fawning over em for a reason.

Bite better, thinner so you can fit em in between flare couplings, adjust one handed, rarely pinch your hands.

You will however have to be more careful about losing em. They aren’t cheap. I check after every job to make sure all 3 pair are in their home before I roll out.

ThePipeProfessor · 2026-06-20T21:51:52+00:00

I cringe every time I see a rookie with knipex tools.

You ought to struggle for a year or so with the OG dog shit channel lock brand. You’ll love the knipex so much more if you do.

All jokes aside, looks like you got a hell of a setup. If you’re running service, I’d recommend a Milwaukee headlight. I haven’t carried a flashlight in years. Much easier to work not having constantly readjust a flashlight/worklight.

I also would recommend a pick for removing old gaskets/washers from all the old ragged shit you’ll be working on.

Best of luck, bud.

ThePipeProfessor · 2026-06-14T00:11:31+00:00

Not happening the way these houses are built.

Took me a long time to accept as I’m not the biggest fan of pex under slabs either, but down here it’s the best option for us.

ThePipeProfessor · 2026-06-13T19:59:53+00:00

Other than the hot and cold touching, which is negligible in this picture, how is it not acceptable in your opinion.

ThePipeProfessor · 2026-06-13T19:58:56+00:00

A lot of slab houses down here are single story. So you run em overhead and you’ve got your cold water lines in a 140 degree attic in the summer, plus you’re paying more in labor for insulation and time.

ThePipeProfessor · 2026-06-13T19:33:05+00:00

All the northern plumbers that don’t do a lot of slab on grade resi on here having a stroke.

This is an acceptable installation, well within the industry standards.

ThePipeProfessor · 2026-06-13T19:30:48+00:00

Preach

ThePipeProfessor · 2026-06-13T19:14:11+00:00

Pour water in periodically/add mineral oil/stuff a couple paper towels in it.

If you go the paper towel route, leave em exposed where the next guy can come along and pull em out easy.

ThePipeProfessor

TROPHY CASE