doors

Doors are movable barriers that regulate passage between spaces, offer privacy, and provide security and protection from weather. They are typically attached to a door frame with hinges, or mounted on a track for sliding; some doors rotate or pivot. Doors can be operated manually or automatically by sensors, switches, or access-control systems.

Common types include hinged doors, sliding doors, pocket doors, bi-fold doors, French doors, and revolving doors. Exterior doors are designed for durability, weather sealing, and security, while interior doors emphasize privacy and sound insulation. Fire-rated doors are used where building codes require protection against fire spread.

Materials range from wood and solid or hollow metal to glass and engineered composites. Many doors consist of a core (such as wood, foam, or particleboard) with a decorative or protective skin. Hardware such as locks, handles, hinges, strike plates, door closers, and weatherstripping influences security, ease of use, and energy efficiency.

Performance is described by factors including energy efficiency (insulation), air leakage, and acoustic rating. Building codes and standards govern sizing, fire resistance, hardware, and accessibility requirements for public and multi-family buildings.

Installation involves proper frame, hinge mounting, hardware fit, weatherstripping, and sealing, with attention to dimensioning and clear opening width. Maintenance includes inspecting hinges and seals, repainting or refinishing, and replacing worn weatherstripping.

Doors have a long history with early wooden doors in antiquity, evolving with metal and glass in the medieval and modern eras, and continuing to incorporate smart and energy-efficient technologies in contemporary construction.