Your door frame may seem pretty straightforward, but there’s more to it than meets the eye. In fact, most people tend to take their door frames for granted. While door frames can get tricky depending on what type of door you’re working with—interior doors and exterior doors or sliding doors and patio doors—let’s assume we’re looking at an average entry door frame and the basic door frame parts you’ll need to know.


Head & Top Rail

The head is the top of the door frame, sometimes called the “door header.” It may look straightforward or have simple molding. It also includes a stop at the lower edge, along with weatherstripping, to make sure the door closes firmly and creates a proper seal.

Located just beneath the head, the top rail is the top section of the actual door panel.


door parts diagram for single door unitDownload our door parts guide for single & double door units 



Located at the bottom of the door frame, the threshold is the area you cross to pass through the door. It contains the door sill.

The bottom rail is the bottom section of the door panel that moves across the threshold. If you have weathersealing issues, your bottom rail, sill, and/or your threshold may be to blame. Having the proper seal between your door and threshold can lead to a more energy efficient home.


Hinges & Hardware

Door frames come with a lot of hardware. Here are a few of the basic components:

  • Door hinges allow the door to open and close.

  • The horn & holdfasts bind the frame to the rest of the wall.

  • King studs & jack studs are used to join the door frame to the rest of the house frame. These are installed according to code.

  • Locks have specific hardware of their own. Luckily, we’ve written about them here.


Jamb & Margins

The door jambs are the vertical components of the door frame on either side of the door. You may also hear them described as the hinge jamb (for the side with door hinges) and the strike jamb (the side that contains the strike plate and works with the locking mechanism).

Margins (sometimes also called “rebates”) are the spaces between the door and the door frame. These are often important if you’re looking at issues with your hinge jamb. Again, these spaces can be broken down into specific types: the hinge margin, strike margin, top (header) margin, and bottom (sweep) margin.

Read: What Should My Door Margins Be?


Beyond the Frame

Again, other doors may have components we haven’t discussed. (Don’t even get us started on French doors and astragals). While we’ve covered the essential frame components, here are a few more common elements you might like to know.

  • Casing typically refers to interior framing, while Brickmould is the exterior framing to your door frame.

  • For simplicity, we refer to the door panel as the whole swinging door. Keep in mind others may use similar language to describe the panels in the door design itself (often resembling window panes).

  • Sidelights are tall, vertical windows to either side of the door frame.


Show Your Door Frame Some Love!

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