Flange installation question, new floor

[hdsteele]

Hi all, first-time poster. With the reno I have going it won't be the last. I am replacing a bathroom floor and toilet. The old plastic flange was broken so took the top part off and am working on getting the inserted portion out. 4" PVC pipe. Our new floor is higher than the old one. As shown in the pics, the top of the drainpipe is even with the cement slab subfloor but 3/4" below the level of the tile. Trying to find out the accepted way of installing a new flange in this situation. Do I need to add cement so the flange is installed level with the tile? I know there are extender kits but confused about those as well. What are the steps I need to take to install? Hopefully, I'm making a big deal out of nothing but...I'm not a plumber (can you tell?) and don't play one on TV. Any help/assistance is GREATLY appreciated. Thanks,

 

[breplum]

Most all plumbers own tools to clean out the PVC. Pasco Ram Bit 4″ – Winnick Supply
Sioux Chief and others make excellent stainless steel flange PVC closet flanges.
Closet flanges must be secured to the floor with non-corrosive fastners (brass or stainless steel -maybeTapcons)
Sioux Chief also make some gasketed insert-to-pipe closet flanges but may be hard to find with S.S. flanges.
Do NOT use plastic ring closet flanges, they are complete junk and destined to fail.

 

[hdsteele]

Most all plumbers own tools to clean out the PVC. Pasco Ram Bit 4″ – Winnick Supply
Sioux Chief and others make excellent stainless steel flange PVC closet flanges.
Closet flanges must be secured to the floor with non-corrosive fastners (brass or stainless steel -maybeTapcons)
Sioux Chief also make some gasketed insert-to-pipe closet flanges but may be hard to find with S.S. flanges.
Do NOT use plastic ring closet flanges, they are complete junk and destined to fail.

Thanks. I have a 4" hole saw but without a place to center the bit that is iffy for someone like me, inexperienced in doing it. I'm going to keyhole saw some reliefs and try to chisel it out. I don't see any evidence of primer so hoping the joint isn't welded. My basic question is whether or not I build up the base and install the flange level with the tile or do I install it at slab level and then get an extender that goes on top? If I build it up that is going to decrease the overlap/glue area of the joint by 3/4". Not sure (obviously)..

 

[breplum]

Chiseling out is a good old way, depending on degree of glue adhesion. But once you start chiseling, you doom the Rambit method. But it takes some finesse.
Forget hole saw. Rambit is worth using!!!!
Code wants a flange to be mounted to top of floor, but we often don't have that luxury.
There are lots of WC flange spacers on the market. Depends on what your suppliers stock.
You can space up the flange using small pieces of 1/2" copper tube.
I would shove the new closet flange down, secure into concrete, and build up off the flange with WC spacers.
They come in kits of three and get caulked together to build up to floor level. Throw away the junk plated steel closet bolts that ship with those kits and use long brass closet bolts, stainless steel washers and brass nuts both to stabilize the spacers and also to set the toilet.
A good plumber should be able to do this in less than an hour. Well worth the expenditure.

 

[hdsteele]

Thanks. I figured it out. The old flange wasn't glued at all and once I made two relief cuts and chiseled out a 3" piece the rest pulled right out. I figured out the spacers. Too embarrassed to tell you what I was doing. Let's just say I was trying to line them up incorrectly. Once I stumbled across that magic trick it's fine. Flange on the slab, two spacers with silicone caulk between all three and height above the tile is about 1/8". Haven't done it yet but I believe my only hurdle will be making sure I have the flange seated correctly before PVC glue takes hold. Gotta be quick. But..I'm willing to bet you knew that. There doesn't seem to be a way to do a dry fit first as I don't think it will come back out. At least not easily. There's probably a tool for that as well! Is there a way to test fit? Any secrets to getting a flange back out after fitting it?

Yes, a plumber is always better (not sometimes, ALWAYS). We are renovating our guest house HVAC guys, electricians, roofers, stone countertop installers, etc. all roaming around at various times. I thought I would just try to save a couple of $$$ by switching out the toilet and sink myself. I think I would rather go on the roof and replace 6,000 metal roof screws than mess with plumbing!

 

[breplum]

Dry fitting/test fitting plastic piping layout is done in almost all cases.
We use Listo wax markers to make alignment marks so that during the glue-in process we get the alignment dialed in.
But, we don't usually push in fully bc it sure is hard to pull apart. No special tools yet for that.

 

[hdsteele]

Thanks. I'm good, finished install. Test fit as far as I dared and then glues it up. Needed a couple of rubber mallet taps is all. 1/4" spacer on top and it was proud of the surface by about an 1/8". Will ask one last amateur question, hardware store tried to sell me a "spin on" type of flange. Had a black gasket that tightened as you spin. What is inherently wrong with those? Something has to be or you guys would use them and I don't see them mentioned anywhere. Thansk gain for the help.

 

[breplum]

Was it UPC approved? That is a shield shaped symbol with UPC inside.
There are quite a lot of grey market plumbing ideas. If they haven't been tested to meet health and safety practical standards, or if the company is so small, or the product so low in potential sales volume, it may not be practical to have submitted to IAPMO for testing approval and listing as reliable.
Rubber gaskets if in contact with effluent might break down in a friction fit situation and we DO sometimes have to resort to off-market solutions.
Many of these products and companies enter the market and disappear for any number of reasons.
A great idea without deep financial backing: you can guess...
How 'bout show what you did?