A door frame—also called a door surround or door jamb and head—is the rigid structure that supports a door’s operation and security . It typically consists of:

• Jambs: Vertical side pieces (hinge jamb & strike jamb) that hold the door and receive hardware
  

• Head Jamb (Lintel): Horizontal top member that spans between the side jambs
  

• Threshold/Sill: Bottom horizontal piece (optional in interior frames) providing stability and sealing .

• Door Stop/Stopper: A molding or lip that stops the door from swinging past the closed position
  

Materials vary by application and include:

• Wood: Common in residences; offers insulation but requires upkeep .

• Metal (steel/aluminum): Durable, fire-rated, and ideal for commercial settings
  

• Fiberglass/composite/vinyl: Weather-resistant and low-maintenance options .

Profiles & joinery styles:

• Mitered: Frames with clean, seamless 45° joints
  

• Butted: Frame head sits atop side jambs; offers a shelf-like look
  

• Pre-hung: Door comes mounted in frame, ready-to-install; differs from slab-only door sets