Typical signs
- Straight crack at a joint, opening corner or fastener visible below paint.
- A defect that returns after each repair or changes seasonally.
Where it is often found
- Ceilings, wall corners, panel joints, around doors and at structural transitions.
What it can mean
- Wood or joint-compound shrinkage.
- Insufficient fastening, moving backing or more significant differential movement.
What to check next
- Photograph shape and length.
- Check whether nearby doors, floors or structure show movement too.
Reasonable immediate actions
- Mark the ends and monitor before finishing.
- Repair only when the substrate is stable and dry.
When to stop and call a professional
- Rapid widening, displacement, sagging ceiling or several structural symptoms.
Prevention
- Adequate fastening and backing, acclimation, humidity control and proper joints.