Toilet Flange - 4x3 or drop flange in 3 inch PVC?

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Sounds good. I already have primer/cement - can I just use them vs the blue stuff?
We caulk them to the floor. Some codes allow a little space in the rear to let water out.

Personally I caulk them all the way around.

Yes, you can use the glue you have if it’s not jelly. Use plenty of glue, it acts as a lubricant to assemble the pieces.
Is this the blue glue you are talking about? If I can get rid of the priming step, then why not?

https://www.lowes.com/pd/Oatey-8-fl...ukUpazDuXrlHEZHb7axoCiysQAvD_BwE&gclsrc=aw.ds
 
That’s the glue but if you already have the other, save yourself $15.
Just got back from Lowes, and it dawned on me that the reducer will not fit through the floor to be able to glue it on the 3 in pipe below. Looks like I'm gonna end up trying the drop flange I guess. :(
 
Just got back from Lowes, and it dawned on me that the reducer will not fit through the floor to be able to glue it on the 3 in pipe below. Looks like I'm gonna end up trying the drop flange I guess. :(
Trim the floor out just so it barely slips through
 
Don’t cut too much. You want to keep it tight so you’ll have something to secure your flange to.
Got the hole cut perfectly in the floor. The PVC cut nicely too, but it didn't end up being as flush as I'd like - will gluing the reducer on the the pipe be ok? Here's a pic of what I cut out if it gives you an idea. Thanks.
 

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So you’re showing me a crooked cut.

It would be ok if you straightened the cut some. You need to straighten that cut. Just trim the high side down.

It’s hard for me to see the cut. You’d have to flip it over and gave the cut side up and hold it level with the camera.

But no need for me to really see it. The cut needs to be at least within 1/4” from perfect……

We want a quality joint there, it’ll be there a very long time.
 
So you’re showing me a crooked cut.

It would be ok if you straightened the cut some. You need to straighten that cut. Just trim the high side down.

It’s hard for me to see the cut. You’d have to flip it over and gave the cut side up and hold it level with the camera.

But no need for me to really see it. The cut needs to be at least within 1/4” from perfect……

We want a quality joint there, it’ll be there a very long time.
Ok, gotcha, that's what I figured the answer would be - I'll work on it.
 
Ok, gotcha, that's what I figured the answer would be - I'll work on it.
So everything went well with leveling off the pipe. However, when I went to set the reducer, I got in on the pipe and it would go no further no matter what. Am I screwed? That blue stuff bonded almost instantly and would allow me to budge it. Tried knock it gently with a hammer and everything....tell me I don't have to rip everything out....
 

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Remember your glue also acts as a lubricant, apply liberal amount to both pieces and work very fast. Read the last sentence of post number 20 that I made.

It’ll be ok, looks like you cheated it 1/2”. That glue is awesome, it’ll hold. How wide is that gap ?

When you glue your 4” pipe into the hub, sometimes it’s easier to just use a long piece then use an oscillating tool to cut the pvc flush with the finished floor. Then your flange glued into the pipe. Sop it up good with glue.

Protect your floor from the glue. Very important. Don’t spill it.

Remember to use plenty of glue and work fast. Wipe away excess glue if you can.
 
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Remember your glue also acts as a lubricant, apply liberal amount to both pieces and work very fast. Read the last sentence of post number 20 that I made.

It’ll be ok, looks like you cheated it 1/2”. That glue is awesome, it’ll hold. How wide is that gap ?

When you glue your 4” pipe into the hub, sometimes it’s easier to just use a long piece then use an oscillating tool to cut the pvc flush with the finished floor. Then your flange glued into the pipe. Sop it up good with glue.

Protect your floor from the glue. Very important. Don’t spill it.

Remember to use plenty of glue and work fast. Wipe away excess glue if you can.
That gap is about a half inch, maybe a bit more on the other side, but is seems very level. It would not budge. Think it will be ok?

I took your advice and glued the whole piece of 4" PVC then cut it. That twisted in much better than the reducer did and went all the way to the hub.

Before I glue the flange in, just want to make sure I'm putting the right one in, as it seems to dry fit a lot easier than the other pipes. This is the one:

https://www.lowes.com/pd/Oatey-PVC-Flange/50315057
 

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It’ll probably be ok. I like full make up but anyone who tells you all of their joints are 100% made up…….is lying to you.

Yes, that’s the correct flange. Sip it up with glue, slam it down and hold it for a minute. Then predrill your screw holes and anchor the flange allowing the closet bolts to be center of the pipe on each side.
 
It’ll probably be ok. I like full make up but anyone who tells you all of their joints are 100% made up…….is lying to you.

Yes, that’s the correct flange. Sip it up with glue, slam it down and hold it for a minute. Then predrill your screw holes and anchor the flange allowing the closet bolts to be center of the pipe on each side.
If it were you would you cut it out and redo it? Or would I be insane to do so?
 
If it were you would you cut it out and redo it? Or would I be insane to do so?

I wouldn’t cut it out if it was 1/2” short with blue glue. It shouldn’t be holding water and if it does ever hold water it wouldn’t be much, so no pressure.

The blue glue provides a very very strong bond. Pvc fitting hubs offer a taper fit. The get smaller as the pipe pushes home to the make up. The make up is where the pipe meets the fitting at it’s maximum depth.

Next time use more glue. I can see you didn’t use enough on the fitting hub to lubricate it enough. Sop it UP on drainage fittings.

You could always go into the crawlspace and check it I guess.
 
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I wouldn’t cut it out if it was 1/2” short with blue glue. It shouldn’t be holding water and if it does ever hold water it wouldn’t be much, so no pressure.

The blue glue provides a very very strong bond. Pvc fitting hubs offer a taper fit. The get smaller as the pipe pushes home to the make up. The make up is where the pipe meets the fitting at it’s maximum depth.

Next time use more glue. I can see you didn’t use enough on the fitting hub to lubricate it enough. Sop it UP on drainage fittings.

You could always go into the crawlspace and check it I guess.
Thanks for all the assistance. Next time I'll definitely use more glue. I think it's because I really didn't have a good angle from up top to try and twist and push etc. Next time our pest guy is out I'll send them under and ask to check for leaks - I hate crawl spaces hahaha. Like you said, it's a vertical pipe and waste goes straight down without hanging out much. I'm a basement guy all day - moved from Syracuse, NY down here to Greenville, SC, and still getting used to residing over a dirt pit 😆

Time to go spray some great stuff pest foam around that pipe before I set the flange!
 
Of course it is too late now, and you hopefully won't need to do this again, but working with a fitting alone below floor level can be hard to do. If you had glued the 4" pipe to the reducer first, it would have been easier to twist and push the reducer to the drainpipe below the floor and get a good full depth joint. But like Twowaxhack said, it will probably be OK, and I wouldn't redo it either.
 

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