To supersede the requirement for top plates stated in Sentence (1) and permit lintels with splices to serve the function of the top plates.
These minimum dimensions for metal splices, and wood splices and their fasteners are to limit the probability of discontinuous support at the ends of lintels, which could lead to lintels being unable to resist expected lateral loads, which could lead to the excessive deflection or failure of walls.
For floors and constructions supporting floors, this is to limit the probability of:
This is to limit the probability of excessive movement, vibration or deflection of floors, which could lead to negative effects on the psychological well-being of persons.