Backsplash
A wet backsplash can be a supply, a waste, or the sink.
Dark grout and a soft cabinet ceiling are the usual clues. Tile is expensive to open. Narrow the source before anyone starts a renovation.
Check the stops and the sink flange first.
Many ‘wall leaks’ are still the sink.
Do not start a backsplash renovation as leak detection.
You can destroy the stain map and still miss the pipe.
The suite below may already know.
Ask before you assume the water stayed in your cabinet.
Questions people ask
Can thermal imaging see behind tile?
Tile and foil can limit what a camera shows. A limitation should be written down.
Is this always the dishwasher?
No. Supplies, wastes, and the sink itself share that wall.