WallProof01 / Wall location
Before you drill
Understand concealed-object signals, wall construction and the checks that a detector cannot replace.
A wall scanner can help locate possible objects. It cannot certify that an area is free of services or that a fixing will carry a load. Begin with the construction, available records and the instructions for your exact instrument.
Start with these two guides
Can you trust a wall scanner before drilling?
What a detector adds to the decision — and what it cannot establish.
Why wall materials change scanner readings
How linings, hidden metal and mixed construction complicate a scan.
Follow the question, not the colour of the light
- “Nothing was detected.” Check that the tool, mode, surface and target type are compatible. A missed target is still possible.
- “Something is detected everywhere.” Consider the wall build-up and possible widespread interference, rather than assuming a wall full of pipes.
- “It looks like a stud.” An object indication does not establish its identity, condition or load capacity.
These starting points follow the Bosch GMS 120-27 safety instructions, not a claim that every detector behaves in the same way.
When to pause
If services may be present and their route remains uncertain, pause intrusive work and obtain competent help. Repeated passes that produce inconsistent signals are a reason to investigate further, not to choose the most reassuring reading.
The materials index connects common wall layers to the relevant explanations. For instrument readiness, see checks and calibration, including a clearly labelled wall-scanner example.
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