How do I determine door handing?
Stand on the outside of the door (the side from which you would push to enter or the 'key side' / 'secure side'). If the hinges are on your left, it is a left-hand door. If the hinges are on your right, it is a right-hand door. If the door swings away from you, it is standard handing. If it swings toward you, add 'reverse' to the designation.
What is the difference between left hand and left hand reverse?
A left hand (LH) door has hinges on the left when viewed from the outside and swings away from you (inswing). A left hand reverse (LHR) door has hinges on the left when viewed from the outside but swings toward you (outswing). The reverse designation indicates the swing direction is opposite of standard.
Can door handing be changed in the field?
Changing door handing requires re-prepping the door and frame for hinges and hardware on the opposite side. On fire-rated assemblies, this is not permitted because field modifications void the fire label. Even on non-fire-rated assemblies, field re-prepping is labor-intensive and may not produce a clean result. Ordering the correct handing is significantly less expensive than correction.
Does handing affect hardware selection?
Yes. Some hardware is hand-specific, meaning a left-hand version cannot be used on a right-hand door. Exit devices, closers with specific arm types, and some lever trims are examples of hardware that may be hand-specific. When handing is changed, all hand-specific hardware must also be changed.
What are the most common situations where handing is specified incorrectly?
Common handing errors include confusing left and right by standing on the wrong side of the opening, forgetting to account for reverse swing, and not updating handing when architectural plans are mirrored during design revisions. Double-checking handing at the field measurement stage prevents most of these errors.