Detection and repair are different stages
Non-invasive or non-destructive leak detection describes checks that can gather evidence without opening every suspected surface. Thermal imaging, acoustic listening and suitable system testing may help narrow the investigation. The choice of method depends on the pipework and conditions, not simply the phrase used to advertise it.
When access is still needed
A concealed joint cannot usually be repaired through a temperature image or sound reading. Once the evidence supports a position, the engineer explains the physical access needed to confirm the source and repair the plumbing. The purpose of tracing is to make that decision better informed.
Questions to ask before booking
Ask which work the quote covers: detection, access, repair, materials, testing and reporting. Also ask who restores the surrounding finish. Track N Fix includes access and plumbing repair in the residential package, while decorative and remedial reinstatement remains separate.