Rough Opening: Dimensions of the opening in the framework of the home that require the installation of a complete door unit (allowing clearance on top and each side for stabilization shims).

Threshold: The bottom sill of the door unit which acts as the bottom of the frame unit. It achieves the water and air barrier that meets with the door sweep.

Transom: A piece of decorative glass placed atop the doorway.

Sidelite: The side panels beside a door, typically filled with glass for decoration and to allow more light.

Inactive Door: In a double door unit, this is the door that has the T-Astragal and the flush bolts. This door will also act as a secondary entrance. It can lock or unlock using the flush bolts to allow the door to swing or not.

Lockset: The complete handle-set with locking system.

Flush Bolt syterm: (Double doors only) Flush bolt system on top and bottom of double doors locks in dominant door