Redoing bathroom. Galvanized is cracked. How to proceed?

[NoviceLurker]

Opened up the wall and the galvanized is cracked. After the 90 on the right it goes up about three feet and then left about six feet to vent stack.

The cracked section need to be cut, obviously. When I do, do I cap the rest of the galvanized or do I tie back into it? If I cap it, how should the AAV be constructed?

 

[Terry]

It's always best to have vents up through the roof. You should never have to worry about them again.

If you use an AAV on the sink, it can be between the p-trap and the wall, at least 4" above.

Or if you install a box higher than that, get the one with the venting grill. It has to be able to pull in air.

 

[Sponsor]

 

[Jeff H Young]

I'd probably replace the Santee as well and if there is a basement below might run new pipe through the floor then I'd cut the gal above the 2 90s and replace that. AAV ? for what? you have a vent

 

[NoviceLurker]

I’m about 40ft below the roof in the basement. Not below ground. The reason I say bypass it is I believe it was cut and capped in another area in the house two floors up. That bathroom was redone and had really bad galvanized in it and they capped it I’m certain and added an AAV. All the toilets go right to the main stack as well as the showers and sinks in the rest of the bathrooms in the house.

The main stack is about five feet to the left of that drain. There’s a crawl space, but getting rid of all of the galvanized will require most likely taking up the floor.

I have to see if I can fit 4” above the trap with the vanity. Hopefully I can in some way?

 

[NoviceLurker]

The attached photo is how I’m thinking of doing it. I will cut the galvanize off a few inches above the galvanized T. The attached photo comes off of that into the vanity. The top part I will also connect to the existing galvanized. If it’s blocked off I have the AAV in the vanity. If it’s not, I have two air intakes. Is there anything that’s an issue here? I added a clean out because there’s nothing right now and a snake getting through the sink drain and then immediate right then immediately down then another left turn was impossible when I tried to snake it.

 

[Jeff H Young]

AAV needs to be installed vertical? not clear what your doing. Are you planning to cap the galvanized? wont it trap condensation or water?

 

[NoviceLurker]

AAV needs to be installed vertical? not clear what your doing. Are you planning to cap the galvanized? wont it trap condensation or water?

The way you’re looking at it is the way it’ll be installed vertical. AAV is “up.” I drew on the original picture to see my thinking. Red lines is where I intend to cut the galvanized.

 

[Jeff H Young]

OK but why an AAV when you are tying to a vent? No need for an AAV

 

[wwhitney]

Best practice is to replace or abandon all accessible galvanized. If you want an AAV under the sink, easiest is to put it on the trap arm. Then in the wall you have an elbow instead of a san-tee.

Jeff, the OP commented earlier that he doesn't believe the vent is still connected to the roof, so it's not viable.

Cheers, Wayne

 

[NoviceLurker]

OK but why an AAV when you are tying to a vent? No need for an AAV

As a backup if it is, in fact, capped somewhere.

 

[NoviceLurker]

Best practice is to replace or abandon all accessible galvanized. If you want an AAV under the sink, easiest is to put it on the trap arm. Then in the wall you have an elbow instead of a san-tee.

Jeff, the OP commented earlier that he doesn't believe the vent is still connected to the roof, so it's not viable.

Cheers, Wayne

Wayne, I don’t think I have length from wall to ptrap to put one in. Also, the ptrap pipe is the thin regular ptrap that you buy for $7. It’s not the regular plumbing PVC 1 1/2. Would you cut it under the galvanized T and use the shielded coupler or just use a 90 degree rubber? Open to all suggestions that are possible without removing a floor or wall lol

Added more photos.

 

[wwhitney]

Suggestion:

1) Cut the galvanized near ceiling; since you say it may still be connected, use a shielded rubber coupling to connect to new plastic.

2) I don't recognize the fitting at the bottom of the galvanized drain that is just visible in your picture with the trap. But with a picture from the front, perhaps it will be recognizable. Hopefully it is something that you can take apart and reconnect plastic DWV to. Otherwise, cut galvanized just above and use another shielded rubber coupling to connect to new plastic.

3)Run a new drain/vent with san-tee where you want it.

4)For AAV, see if something like Magic Trap would work for you. Otherwise if you have room in the vanity cabinet, you could put a wye above the san-tee and let the branch inlet come into the vanity, then hit a 45 and an AAV. Or you could put one higher up in the wall in a ventilated wall box.

https://rectorseal.com/products/other-mechanical-products/magic-trap-kit/

Cheers, Wayne

 

[NoviceLurker]

Suggestion:

1) Cut the galvanized near ceiling; since you say it may still be connected, use a shielded rubber coupling to connect to new plastic.

2) I don't recognize the fitting at the bottom of the galvanized drain that is just visible in your picture with the trap. But with a picture from the front, perhaps it will be recognizable. Hopefully it is something that you can take apart and reconnect plastic DWV to. Otherwise, cut galvanized just above and use another shielded rubber coupling to connect to new plastic.

3)Run a new drain/vent with san-tee where you want it.

4)For AAV, see if something like Magic Trap would work for you. Otherwise if you have room in the vanity cabinet, you could put a wye above the san-tee and let the branch inlet come into the vanity, then hit a 45 and an AAV. Or you could put one higher up in the wall in a ventilated wall box.

https://rectorseal.com/products/other-mechanical-products/magic-trap-kit/

Cheers, Wayne

Wayne, you talking about this? It’s a 90 cast iron I believe that goes left to the stack.

 

[wwhitney]

Yeah, I think it may be a threaded connection?

In which case you could in theory unscrew the galvanized and screw in a plastic male adapter. But I think I might be a bit afraid to try that, it would be safer to cut the galvanized 3" up and use a shielded rubber coupling. Assuming that after you cut the galvanized, it isn't completely clogged with interior rust.

Cheers, Wayne

 

[NoviceLurker]

Yeah, I think it may be a threaded connection?

In which case you could in theory unscrew the galvanized and screw in a plastic male adapter. But I think I might be a bit afraid to try that, it would be safer to cut the galvanized 3" up and use a shielded rubber coupling. Assuming that after you cut the galvanized, it isn't completely clogged with interior rust.

Cheers, Wayne

Threaded, yes. I’m going to put the vanity in place and see if I can put the AAV right on top of the galvanized and put a vent box in the wall and still have access to it through the vanity.

 

[NoviceLurker]

Yeah, I think it may be a threaded connection?

In which case you could in theory unscrew the galvanized and screw in a plastic male adapter. But I think I might be a bit afraid to try that, it would be safer to cut the galvanized 3" up and use a shielded rubber coupling. Assuming that after you cut the galvanized, it isn't completely clogged with interior rust.

Cheers, Wayne

Wayne, would this save me a world of time? It’s like the one you suggested, but looks to be better length wise and might fit. I’d probably still cut and cap the galvanized and make a clean out like I want to inside the vanity.

Oatey 39225 1.5" 6 DFU Sure-Vent AAV 1-1/2" Tubular adapter (white) one-way valve https://www.amazon.com/dp/B0069KDHS...abc_KB8GDFYR446S1ZDHX4JX?_encoding=UTF8&psc=1

 

[wwhitney]

Yes, that seems like a useful option, very similar to the Magic Trap I linked to, but perhaps slightly more convenient. You have control on where the san-tee ends up, so you can pick a height and/or offset from sink center so that the whole thing from the bottom of the trap to the top of the AAV will fit within your vanity cabinet.

Cheers, Wayne

 

[Jeff H Young]

Best practice is to replace or abandon all accessible galvanized. If you want an AAV under the sink, easiest is to put it on the trap arm. Then in the wall you have an elbow instead of a san-tee.

Jeff, the OP commented earlier that he doesn't believe the vent is still connected to the roof, so it's not viable.

Cheers, Wayne

So it would be a bad idea to hook his PVC vent to the galvanized as he planned in pic from post 5 ( it seemed like a pointless )

 

[NoviceLurker]

Cut out the galvanized way down so I can start fresh with PVC. It’s a very tight fit and can’t use the inline vent that comes off of the ptrap like @wwhitney had suggested. I had wanted to make sure that there was a clean out and it became a mess and was difficult to fit everything in there. The vanity is 18” wide and that’s as wide as I can go without encroaching on the toilet. It took a lot of trial and error dry fitting and I THINK I make have found a solution to it all. The clean out can be just taking off the whole ptrap and going right into the pipe. My only concern is if that 90 degree the ptrap will be an issue. If not. Yay. If it is, please make suggestions as I don’t know what to do except send the vent up in the wall and create some sort of access which would look terrible.

 

[Reach4]

Ideally, you would have come out of the santee with a street 45. 45 is considered vertical for this purpose. Then another 45 to get back to true vertical. What you did will work fine, however.