• Contractors
• Architects
• Showrooms
• Replacement Parts
• New Products
• Clearance Center
• Rebates and Specials
• Related Services
• Email Alerts

Become a Door Expert

At JB Sash, we are the experts in doors as well! Below are commonly used door terms that will ease the buying process. They include:

Types of Doors

Arch Door: A door with arched top rail and arched frame; a.k.a. Round Top Door

French Door: A door with glass panels separated by wood muntons

Pre-hung: Doors or combinations of doors and sidelights that are put together with jambs, hinges, threshold, T-Astragel and trim (a complete unit)

Rectangular Door: The standard door shape

Parts of Doors

Backset: The distance from the edge of the door to the center of the hole drilled for your entry set knob, lever or deadbolt

Casing: A wooden trim around doors that covers seam between jamb and wall

Frame: The set of jambs that holds the door unit together

Hinge: The metal objects that attach the door to the jamb with screws

Jamb: The wood that surrounds the door unit; it runs vertically between the header and the sill or threshold

Knob: Round part of door handle

Lever: Term used for a knob when it is long and thin, not round

Lintel: A decorative carving on the wall just above the door

Lockset: The complete set of locking hardware mechanism for a door

Lock/Bored: A lock that fits into the round holes, which are bored or drilled into the face and edge of the door

Lock/Deadbolt: A locking mechanism for an entrance door; available in single or double cylinder

Lock/Flush Bolts: Bolts mounted in a door to lock a door in place; the bolt slides up into the jamb above the door and down into the threshold or floor below the door; generally used on double doors

Lock/Mortise: A lock that is enclosed within the edge of a door so that it cannot be seen or removed when the door is closed.

Moulding: A decorative wooden strip used for ornamentation, carving or finishing

Mull Cap: Interior and exterior trim for seam between door and sidelight

Muntons: Wooden trim that holds panels of glass in the door which makes a style of French door; a.k.a. grille

Slab: Door only – no frame, jamb or parts added to make door operate

T-Astragal: A vertical piece of wooden moulding that fits between double doors to provide an effective weather seal; it attaches to the inactive door of a double door unit; it houses the flush bolt

Threshold: The part of the door unit that is attached to the floor under the door