# toilet flange knockout



## steve77 (Aug 16, 2010)

Can anyone tell me the proper way to knock out the "knockout" center of a new PVC toilet flange?
First: Do I install the flange before knocking it out or after?
I've already (without it installed) given it a couple of sharp raps with a hammer and nothing happens. Its on there solid. ?
Second: Is the upper lip of the flange supposed to sit on the tiles? Or the backerboard under the tiles? (I set the tiles close up to the drain, so I may have to cut away some tile if the flange is supposed to be level 
with the tile.)
Steve77


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## TheEplumber (Jul 20, 2010)

If your not pressure testing the DWV system then you can remove the knock out before setting or get a flange without the knock out. I use a screwdriver or wood chisel on the stubburn ones. Puncture a hole in the knock out and use pliers to peel it away.
The flange should sit on top the tile. Be sure to anchor it to the floor.


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## steve77 (Aug 16, 2010)

Thanks. Done. And its perfect.
steve


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## DangerMouse (Jul 17, 2008)

Yup, those things can be a real PITA to knock out, huh? I just did 2 of them too.

DM


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## the_man (Aug 14, 2010)

I just worked on a hotel that the trim crew got fired from. I spent 2 days getting 13 knockouts from CI drain lines in walls. It was fun :laughing: and pretty lucrative :thumbup:


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## steve77 (Aug 16, 2010)

*fill valve leak*

Can you give me a clue on this: I installed a new fill valve (brand name Korky) and its shutting off when the water fills, but a few seconds later its starts a little hisss which I assume is letting in a little more water. I checked the (new) flapper and it appears properly seated. I flushed it about fifteen times over a period of a couple of hours and it still shuts off initially then starts the hissing.
Its a little toilet with the tank built right onto it, the tank is small, so I did not extend the fill valve at all, leaving it at its shortest height, and did not put in the no-tamper clip.
steve


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## DangerMouse (Jul 17, 2008)

the_man said:


> I just worked on a hotel that the trim crew got fired from. I spent 2 days getting 13 knockouts from CI drain lines in walls. It was fun :laughing: and pretty lucrative :thumbup:


So... they busted them up and let them fall down the drains????

DM


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## rpmnow (Apr 2, 2013)

*Stupid design on those*

OK, so after having trouble with the same thing and reading this thread I attacked it with several hard blows using a large screwdriver and hammer. It eventually started to crack and after it cracked enough I was able the twist and jerk on it with the pliers until the stupid thing came out. Gets an award for user unfriendly design in my opinion, but then too, maybe they're all that way. I hope not to have to find out anytime soon.


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## aircore (Apr 3, 2015)

TheEplumber said:


> If your not pressure testing the DWV system then you can remove the knock out before setting or get a flange without the knock out. I use a screwdriver or wood chisel on the stubburn ones. Puncture a hole in the knock out and use pliers to peel it away.
> The flange should sit on top the tile. Be sure to anchor it to the floor.


Can you still put the tolet in if the flange is below the tile


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## TheEplumber (Jul 20, 2010)

aircore said:


> Can you still put the tolet in if the flange is below the tile


Yes, but it depends on how low.
You may be fine using a jumbo (extra thick) bowl wax or you may have to install a spacer ring- it silicones down to the existing clean flange, then a bowl wax on top of that. Your closet bolts will sandwich it together from the lower flange through the toilet as normal.


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