Uneven substrates lead to flooring failure

This laminate floor has a broken locking joint which is allowing movement between two boards. The result is an audible squeaking noise when the area is walked on.  The locking joint broke soon after installation because the flooring was installed over top of an uneven sub-floor.
National and manufacturer leveling standards are 3mm + or - over 3000mm
Click here for the full national flooring specification for sub-floor leveling and acceptable conditions.