Toilet flange

Started by frisco, October 17, 2017, 09:18:42 AM

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We have a 2015 DB14
The toilet flange has broken.  Before I start disassembling things does any one know if the flange is glued or screwed in?
If glued has anyone had success with repair flange components?


I had to repair a broken toilet flange on our 2012 13QBB. On ours the flange tube is glued to the tube going into the black water tank. I came up with a good way to repair to the flange. Better than new. I will do a detailed writeup on how I did it and the parts required this evening when I have time and post it.




Randy may have a better solution, but let me describe how to fix a broken, glued on flange by chipping it out with a chisel. Let me say that I haven't seen this fitting on an RV but I assume it is the same as home plumbing.

Glued PVC joints can usually be sawed and chipped away leaving the PVC pipe below mostly intact. Depending on access, use a Dremel saw blade, hacksaw or sawzall to make radial cuts in the broken flange near to the pipe flange joint. Break each segment away using pliers. That usually leaves several chunks of the flange still attached. So use a small wood chisel to break them away at the joint.

Then you still may have a ragged PVC pipe. So take a Dremel tool with the grinder attachment and work your way around the pipe until it is resonably smooth and a new pipe flange will fit over it. Then slather both sides with PVC cement and put the new flange in place.

But, lets see Randy's solution first before tackling this project.



Typically the issue with the toilet flange is that either or both of the two recesses molded into the toilet flange to accept the two toilet mounting bolts have broken away  and the toilet will not pull down tight to the bathroom floor pan. Again typically most of, if not all, of the rest of the flange proper intact. So, if that is your problem or if a greater percentage of your flange is intact this repair should work.

I used a stainless steel toilet repair flange which functions as an "overlay" on top of the original flange.  The repair flange is relatively thin and still allows the toilet to seat down against the floor when the two mounting bolts are snugged up. As the two toilet mounting bolts are now retained by the stainless steel flange is should be a "forever repari". I ordered two types of flanges to see which would fit/work the best:  Harvey's Toilet Flange; and Sioux Chief Mfg 886-MR Closet Ring, Stainless Steel. See the attached photos

The Harveys did not match the original flange screw holes as well as the Sioux, the Sioux will allow align with four or five of the original holes as I recall. See more on this below.

Required Modifications to the Souix replacement flange: As the Souix flange is manufactured the flange has a  "rolled" outer edge and a slight roll to the edge of the center hole. This prevents the Sioux flange from sitting down flat on the original flange. To make it work turn the Sioux flange upside down, place it on hard surface i.e. concrete floor, rigid workbench top and "flatten" out the rolled edges. I used a 3/8 inch diameter bolt to assist as a "punch" to get a nice flat surface.

Additional parts: Purchase stainless steel screws the same diameter and head type as the original flange mounting screws. I purchase screws that were slightly longer than the originals to accommodate the thickness of the repair flange and the insure that I got a full thread purchase.  I also purchased stainless steel toilet mounting screws and nuts. No rust frozen screws in the future!

To Install: check the orientation of the Sioux flange, noting the location of the toilet hold down bolt recesses, relative to the mounting screws on the original flange. Remove only the screws from the original flange that line up with the mounting holes in the Sioux flange. Clean and dry the original flange. Apply a silicone seal to the surface of the original flange (not sure this is necessary but I was not taking anything for granted). Orientate the Sioux flange to the align with the chosen mounting holes of the original flange and put the flange in place and install the screws. Alternate tightening the screws so they pull the flange down uniformly against the original flange.

OPTIONAL: As many new flanges only use four or five mounting screws I consider that sufficient. As an option one can check the location of the the Sioux mounting holes that do not line up with original flange holes and determine which could be drilled into the original flange and used as additional mounting points.

Reinstall the toilet on the new flange torquing the two mounting screws alternately to insure the toilet seats nicely against the floor. Put a bead of silicone seal where the toilet base contacts the bathroom floor pan.

Repair is better than new!

Note: while you have the toilet off make sure your ball valve seal, vacuum breaker valve etc are all in good working order. It is easier to work on them when the toilet is out. 

I hope this helps.



One other thing, if you go the Sioux flange round and "flatten" out the rolled edges as outlined below make sure you do not flatten out the "tabs" formed into the two toilet retaining bolt recesses otherwise the bolts will spin and not tighten up. I found when I did my flange fix that the tabs fit into the area broken away on the original plastic flange with no other modification necessary.

I did consider using an angle grinder and cutting the rolled edges off. That seemed like a lot more work that it was worth and flattening out the edges worked just fine.

When I did my flange repair my first thought was to follow a process as pretty much laid out by DavidM. However, after looking at the flange to pipe fitment I could see where I would likely have ended up dropping the black  water tank and replacing all the pipe from the tank up. In my case the "overlay" replacement flange was an easier option. Assess your problem and the chose the best option that will work for you.

Two engineers on this one project that is scary! You have DavidM, a chemical engineer, and me a mechanical engineer, both giving you good advise.


Thanks for your help
I've ordered repair flanges


The comfort of your toilet room should also not be overlooked. Consider adding softer lighting and plush towels or rugs to make it a more relaxing space.