question about toilet drain flange - enough play for tiles?
You can find Flange Extenders at many Home Centers and hardwares. Besides silicone between the original and extender flange, they are meant to be connected to the floor using the provided holes. Two ways of looking at this. On a concrete floor, it is not likely the piping under the toilet is capable of moving, so securing may not be necessary, IF you use the longer bolts and secure the toilet to the original flange. I have installed extenders and used the slots in it (instead of the original flange) to secure the toilet and did use Tapcons into the concrete. I always secure the extender to the floor on wood floors.
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