Door Industry Glossary
Comprehensive A–Z guide to door terminology, materials, hardware, construction, finishes, components, and technical definitions for architects, contractors, builders, and homeowners.
A
Active Leaf
The primary moving door panel in a double door unit that is used most frequently for entry and exit.
Architectural Door
A high-quality door designed for commercial or high-end residential projects, focusing on design, aesthetics, and performance.
ASTM Standards
American Society for Testing and Materials standards that establish quality and performance requirements for doors and components.
Accessible Door
A door designed to meet ADA standards for wheelchair access, wider clear width and lower threshold.
Adjustable Frame
A door frame that can be modified to fit rough opening variations during installation.
B
Backset
The distance from the edge of the door to the center of the bore hole for locks or knobs.
Batten Door
A door constructed from vertical boards held together with horizontal ledgers or battens.
Bore Hole
A hole drilled into the door to accommodate locksets, knobs, or levers.
Bottom Rail
The horizontal structural component at the bottom of a panel door.
Bullet Hinge
A heavy-duty hinge with a rounded, bullet-shaped pin for commercial doors.
C
Casement Door
A door hinged on one side that swings outward or inward like a window sash.
Core Material
The internal material of a door, such as solid wood, hollow core, particleboard, or mineral core for fire-rated doors.
Casing
Decorative trim used to surround a door frame and cover gaps between the frame and wall.
Chevron Door
A door with a V-shaped or zig-zag patterned design on the surface.
Clear Opening
The usable width available for passage when a door is fully open.
Closed Gauge
A measurement used for steel door thickness and frame strength.
D
Deadbolt
A locking mechanism that extends a solid metal bolt into the door frame for enhanced security.
Door Jamb
The vertical frame components that support the door and hold hinges and locks.
Door Slab
A single, unfinished door panel without hardware, frame, or prepping.
Double Door
A door unit with two door panels that meet in the middle without a mullion.
Dummy Door
A non-functional door used for aesthetic symmetry in double door openings.
E
Edge Banding
A protective or decorative material applied to the exposed edges of a door.
Exterior Door
A door designed for outdoor use, providing weather resistance, security, and insulation.
Emergency Exit Door
A door equipped with panic hardware for fast evacuation in commercial buildings.
Engineered Wood
Man-made wood product used for stable, warp-resistant door cores.
F
Fire-Rated Door
A specially constructed door designed to resist fire for a specified period of time, commonly used in commercial buildings.
Flush Door
A smooth, flat door with no raised panels or mouldings.
Frame Kit
A complete set of jamb, header, and sill components for door installation.
Frosted Glass
Obscured glass used for privacy in doors while allowing light transmission.
G
Glass Lite
A section of glass installed within a door, also called a light or window pane.
Grain
The natural pattern, texture, and lines found on wood and wood veneer doors.
Green Door
Eco-friendly door made from sustainable materials and low-VOC finishes.
Gasket
Rubber or foam seal used for soundproofing and weather resistance.
H
Handing
The direction in which a door swings, either left-hand or right-hand, inswing or outswing.
Hollow Core Door
An interior door with a lightweight, hollow interior structure, typically used for bedrooms and closets.
Header
The horizontal frame member at the top of a door opening.
Hidden Hinge
A hinge mounted inside the door and frame for a clean, modern appearance.
I
Interior Door
A door used inside a building to separate rooms, not designed for exterior weather exposure.
Insulated Door
A door with thermal insulation properties to improve energy efficiency and temperature control.
Inswing Door
A door that opens inward into a room or building.
J
Jamb
The vertical side parts of a door frame that support hinges and lock components.
Jamb Depth
The thickness measurement of a door jamb to match wall dimensions.
Joint
The connection point between stiles, rails, and panels in a door.
K
Keyed Lock
A lock operated by a physical key for security on exterior doors.
Knock Down Frame
A door frame shipped unassembled for easy transport and on-site installation.
Knob
A round handle used to operate a door latch or lock.
Kick Plate
A metal or composite plate at the bottom of a door to protect against damage from foot traffic.
L
Lite Door
A door with one or more glass panels installed for light transmission and visibility.
Lockset
The complete assembly of a lock, including knobs, levers, latches, bolts, and strike plates.
Louvered Door
A door with horizontal slats for ventilation, commonly used for closets and utility areas.
Low-E Glass
Energy-efficient glass that reflects heat and UV rays in exterior doors.
M
Moulding
Decorative profiles applied to door surfaces or frames for aesthetic enhancement.
Murphy Door
A hidden or secret door designed to blend into walls, cabinetry, or bookshelves.
Millwork
Custom wood products including doors, frames, casings, and trim.
Moisture Resistant
A door treatment to prevent warping in high-humidity areas like bathrooms.
N
Night Latch
A supplementary lock used for additional security on exterior doors.
No Bore Door
A door without pre-drilled holes for locksets, allowing field customization.
Nailing Fin
A flange on a door frame used for secure attachment to the wall structure.
O
Outswing Door
A door that swings outward away from the room or building.
Overlap
The amount a door covers the frame when closed for proper sealing.
Open Back Frame
A frame design allowing easy access for installation and adjustment.
Oak Door
A popular hardwood door known for strength, durability, and attractive grain.
P
Panel Door
A traditional door style with recessed or raised panels, commonly used in homes.
Pre-Hung Door
A complete door unit that includes the door slab, frame, hinges, and pre-drilled hardware.
Pocket Door
A door that slides into a wall cavity to save space.
Primed Door
A door with a base coat of paint ready for final finishing.
Push Plate
A metal plate on a door for hands-free operation in commercial settings.
Q
Quick Mount
A fast-installation system for door frames and hardware.
Quarter Sawn
A wood cutting method that produces stable, decorative grain patterns.
Quality Control
Inspection processes ensuring doors meet manufacturing and safety standards.
R
Rail
The horizontal structural members of a panel door (top, middle, bottom).
Reeded Door
A door with vertical linear grooves for modern texture and design.
Right Hand Door
A door hinged on the right side when viewed from the exterior.
Roller
A wheel component used in sliding and pocket door systems.
Rough Opening
The framed opening in a wall where a door unit will be installed.
S
Soundproof Door
A door engineered to reduce sound transmission between rooms, often used in offices, studios, and hotels.
Stile
The vertical structural members on the sides of a panel door.
Sliding Door
A door that moves horizontally on tracks instead of swinging.
Storm Door
An exterior secondary door for protection against weather elements.
Security Door
A reinforced door with heavy-duty locks and frames for maximum safety.
T
Threshold
A horizontal piece at the bottom of a door frame that seals the gap and provides weather resistance.
Trim
Decorative or functional woodwork that surrounds doors, windows, and frames.
Thermal Break
An insulating barrier in exterior doors to prevent heat transfer.
Triple Lock
A high-security locking system with three deadbolts or locking points.
U
UL Listed
A safety certification for fire doors, hardware, and commercial door products.
Universal Handing
A door or hinge that can be installed for left or right hand operation.
Urethane Finish
A durable, scratch-resistant coating for wood door protection.
V
Veneer Door
A door covered with a thin layer of real wood over a stable core material.
Vertical Grill
A decorative pattern of vertical bars or lines on a door surface.
Vinyl Edge
A protective vinyl covering on door edges for durability.
W
Weatherstripping
Sealing material placed around doors to prevent air, water, dust, and noise infiltration.
Wood Veneer
A thin layer of real wood applied over a core material to achieve a natural wood appearance.
Warp Resistant
A door construction that resists bending or twisting over time.
White Oak
A strong, durable hardwood commonly used for high-quality interior and exterior doors.
X
X-Brace Door
A utility door with an X-shaped support structure for strength and stability.
Y
Yale Lock
A common type of cylindrical lock used in residential and commercial doors.
Z
Z-Bar Door
A reinforced door with a Z-shaped metal frame for strength and security.
Zero Clearance
A door or hinge design that allows full opening without obstruction.
About This Door Glossary
This glossary provides clear, professional definitions for common and technical terms used in the door manufacturing, construction, architectural, and design industries. It is designed to help customers, contractors, architects, and designers understand door components, materials, styles, and functions.
This glossary provides clear, professional definitions for common and technical terms used in the door manufacturing, construction, architectural, and design industries. It is designed to help customers, contractors, architects, and designers understand door components, materials, styles, and functions.