Record the context
Note the location, approximate age of the concrete and when the crack became noticeable. Mention whether water collects nearby or the two sides appear uneven. Ground-level photos are useful; avoid probing, loading or walking on an unstable surface to gather information.
Separate different conditions
A fine surface crack, an opening across a slab and movement at a joint can require different responses. NRMCA identifies several causes of concrete cracking, including shrinkage and jointing-related conditions. A photo alone cannot determine whether a crack is stable or what is happening beneath it.
Ask what the proposed repair does
Filling an opening may have a different purpose from restoring a broken edge or replacing a panel. Ask whether the method accommodates movement and what preparation is required. The repair should not be described as a structural solution unless that is actually established.
Watch for related issues
Changes in elevation, recurring water and damage that returns after repairs should be raised during assessment. Where damage involves a foundation or structural element, the appropriate specialist may be needed. This guide concerns ordinary residential flatwork, not a structural diagnosis.
Further reading: NRMCA Concrete in Practice. General guidance does not replace a site-specific assessment.