When installing horizontal sliding doors, which measurement is critical for ensuring a proper fit across the frame?

When installing horizontal sliding doors, ensuring the proper overlap is essential for a seamless fit across the frame. Overlap refers to the extent to which the doors cover each other when closed. This measurement is critical because it affects the efficiency of the door's operation, including security, aesthetics, and energy efficiency.

A proper overlap ensures that the doors close entirely without gaps, which can prevent drafts, reduce noise, and improve the overall thermal performance of the elevator entrance. Furthermore, adequate overlap is necessary to prevent any potential pinching or binding when the doors slide open or closed, which could lead to mechanical issues over time.

While height adjustment, width expansion, and leveling accuracy are also important aspects of door installation, they do not directly impact how well the doors meet across the frame. Ensuring the correct overlap is fundamental to the functionality of horizontal sliding doors.