Toilet woes

Hoping you can help with a strange problem - I noticed floor tile grout lines near toilet bowl are getting damp - I dried with a hairdryer but the problem reoccurs within a few hours , even when toilet not flushed. I can’t see/feel any water leaking from waste pipe seal (behind WC) , from cistern, supply line or from fasteners that secure cistern to bowl.
I have attached a couple of photos , the toilet bowl is on the immediate right and the tiled wall is at the top of pics. I wondered if there may be a pipe leak behind tiled walls but I recall that the pipe run at that point has no joins so less likely to be leaking and also you will see in photo 1 the damp patch seems to creep from right to left (toilet outwards) rather than from top to bottom (from wall although that eventually gets damp too).
Any suggestions ? Planning to contact a plumber tomorrow and hoping this is a WC issue since that will be simpler than removing tiles .
Cheers

Not much you can say until it’s investigated it could be going up it could be going down

Dry tissue paper in hand, start high and work down anywhere you can reach should show the area the leak starts from.

Turn water to cistern off if you can, then come back after a few hours and see if water level in cistern has dropped.
Tools required - Pencil to mark water level in cistern.

rpm said:

Turn water to cistern off if you can, then come back after a few hours and see if water level in cistern has dropped.
Tools required - Pencil to mark water level in cistern.

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I can’t actually turn water to cistern off though so assume fill valve will open to maintain water level ?

Kezzaa said:

I can’t actually turn water to cistern off though so assume fill valve will open to maintain water level ?

Click to expand...

Yes it will refill, are you sure you can`t see a Silver isolation valve on the pipe putting water into the cistern? If not can you tie up the float using a length of wood and string or wire?