How can I trim out a supply pipe passing through a tile floor against the toilet base?
The simplest approach is to buy a solid round escutcheon and cut it to fit.

They come sized to fit different pipes, so take a measure of yours.

You would need to take off one side, just about to the edge of the hole, and then probably cut the hole to be a U shape, rather than round.

You could hold it on place with a few dabs of silicone sealer underneath.


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