23+ Parts of a Door Frame (with Detailed Diagram)

Jessica Stone
by Jessica Stone

Replacing your front door is a great way to make a huge impact on the curb appeal of your home. It’s a very simple task that can give your home the update it may need. If you’re knee-deep in door shopping and are overwhelmed by all of the technical terms, you’ve come to the right place.

Whether you are shopping for a new door or there is a door in your home in need of repairs, you can benefit from learning the parts of a door frame. Although there are many components to the entire door, the parts of a door frame can be broken down into the sill, threshold, door sweep, door jamb, head, margins, and astragal.

Let’s explore all of the different components that make up a door and how they come together. That way, when you’re speaking with contractors or dealers, it’ll be much easier to be on the same page and achieve the look you want.

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What is a Door Frame?

Put simply, a door frame is the entire framework that supports a door. It is an assembly that is comprised of both vertical and horizontal members, which are placed at the top, bottom, and sides of an opening. The frame forms an enclosure that provides the necessary support for a door.

In most cases, door frames are made of wood. Though, recent developments have brought about different materials, such as metal, marble, precast concrete, aluminum, and even granite.

Parts of a Door Frame

While your door frame may seem pretty straightforward, there is much more to it than meets the eye. The door frame refers to the entire framework that supports the door. This includes the sill, the head, and the jamb.

Door frames can be constructed of aluminum, wood, or other materials, and are designed to blend effortlessly into your home. They can become rather tricky to understand when you consider all of the different types of doors – sliding doors, exterior doors, patio doors, and interior doors.

However, let’s explore the standard entryway door and all of the basic parts that make up the frame:

1. The Sill

The sill is the area located at the base of the door frame. It rests on the floor and is the spot that you physically cross over to pass through the door. This is the part of the door that is fastened to the floor.

2. Threshold

The threshold is a decorative element of the frame that serves as a transition between the floor of the room and the door sill. They can be simple or more elaborate, depending on your aesthetic.

3. Door Sweep

This part of the door sits atop the sill and its purpose is to make the door weathertight. Door Sweeps are primarily used on exterior doors to add rigidity to the frame and provide a proper seal between the sill and the frame.

They are typically made of durable materials like fiberglass or metal, as they need to be strong enough to tolerate foot traffic. If you’re experiencing any issues with weather sealing, your door sweep, sill, or threshold is likely to blame.

4. Door Jamb(s)

Often referred to as simply the ‘jamb’ or the ‘side jambs,’ this component is the vertical sides of the door frame. These are the parts of the door that the door itself is secured to. You may also hear these components referred to as the ‘hinge jamb’, for the side with the door hinges, and the ‘strike jamb,’ for the side that houses the strike plate and interacts with the locking mechanism.

To learn more about Split Jamb Door Frame, refer to What Is A Split Jamb Door Frame?

5. The Head

The head, or head jamb, is the top part of the door frame that runs horizontally.

6. Margins

Although not technically a part of the door frame, margins are the physical spaces that exist between the door and the frame. If you’re having issues with your jambs, this component is especially important. Margins, or sometimes called ‘rebates,’ can be separated into specific types: top (header) margin, bottom (sweep) margin, strike margin, and hinge margin.

7. Astragal

If your door is comprised of a pair of doors, the astragal is the vertical segment that is situated between them. It runs from the head of the frame to the sill.

Beyond the Frame

There is much more to a door than just the frame. The ‘panel,’ or ‘slab,’ is the term that is used to describe the door itself and is the piece that physically swings open and closed. Some other door related terms that you may come across include:

  • Rails: The rails are the narrow horizontal pieces connected to the door panel. The number of rails a door has will depend on the particular design.
  • Stiles: The stiles are the narrow vertical pieces found on either side of the door panel. They are appropriately named as the ‘lock stile’ and the ‘hinge stile.’
  • Mullion: Mullions look similar to stiles. They are vertical pieces that separate two panels and are found in the middle of the door in between the rails.
  • Fixed Panel: This refers to the panel, in a pair of doors, that stays in place and does not open or close.
  • Casing: Door casing trim is intended to conceal the gaps between the door frame and the interior wall. These are also seen on windows.
  • Sidelights: This is the term for tall narrow windows, often found on one of both sides of an elaborate entry door. They exist outside of the frame. Sidelights can be a great choice to add more light to your entryway, enhance views to the outside, and create a more welcoming entry space.
  • Transom: Like sidelights, transoms are common on very intricate entryway door designs. They are narrow windows that are positioned above the actual door. In most cases, transoms are non-operational. If they do open, they will have a hinge at the top, like an awning window.
  • Bore Hole: The bore hole is a pre-drilled hole found in a door to fit a lockset.
  • [b]Sash: [/b]A sash is a moveable component that may be found in a door. More specifically, it is the framework in which panes of glass are set into a door, or window.

Keep in mind that, for simplicity’s sake, the door panel is used to describe the entire swinging door. However, some use the word ‘panel’ to describe individual panels in the entire door design, similar to window panes.

In-Swing vs. Out-Swing

When it comes to ordering replacement components for a door or a new door entirely, it’s important that you are aware of all the pertinent terminology. This includes the swing of the door, which basically refers to how the door opens: in-swing or out-swing.

The choice between having your door swing into a room or out of a room when opened can impact the doors, fit, style, and functionality. In simplest terms, it is an in-swing door if you have to push it to enter. Whereas, if you have to pull the door to enter, it is considered an out-swing door.

Door Frame Hardware

Door frames come outfitted with quite a bit of hardware for them to function properly. The following are some of the basic hardware components to a door frame:

  • Door hinges are the jointed mechanism that allows you to pivot a door panel open and closed. Standard doors will have three hinges, but larger ones may have four or more.
  • The horn and holdfasts are the mechanisms that secure the frame to the interior wall.
  • King studs and jack studs are what are used to connect the door frame to the rest of the house. They must always be installed according to code.
  • Locksets contain very unique hardware, specific to the type.

Parts of a Lockset

The term ‘lockset’ is used to describe the combination of the handles (knobs), latches, strike plates, locks, and all the additional hardware pieces that allow you to latch and secure a door in place. Some of the parts of a door’s lockset include:

1. The Handle

The handle, lever, or knob is the part of the door hardware that is used to unfasten the door panel and push it closed or pull it open. They come in a wide range of materials, such as satin nickel, antique brass, and rubbed bronze. There are a number of styles to choose from, with the most common types of door handles being:

  • Entry handles are operated using a key cylinder on the outer side of the door and a turn or push lock button on the inside.
  • Passage handles do not contain a locking mechanism.
  • Bath/Bed handles have a turn or push lock button on the interior, but not on the outside.

2. Latches and Deadbolts

The door latch is what secures the panel in place. It is a shaft that protrudes out from the edge of the door panel and inserts into the frame. When the handle, or knob, is turned, the latch retracts and allows you to open the door.

Deadbolts, on the other hand, are similar to latches in that they are a shaft that protrudes from the outer edge of the door panel and into the frame to fasten it in place. However, deadbolts are considered a supplementary form of security and are usually separate from the door latch. As a result, deadbolts usually necessitate an extra bore hole.

Interior doors do not contain deadbolts and not all exterior doors are equipped with them. They are the most secure way to lock a door as they must be engaged when the door is shut. Their unique locking mechanism built into the bolt prevents any unwanted entry. Deadbolts work by turning a thumb turn on the interior of your house and a key cylinder on the outside.

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3. Strike Plate

The strike plate is another piece of the lockset. It is fastened to the door jamb, where the bore hole for the bolt and the bolt itself meet. Strike plates are essentially a small metal plate that is secured to the door jamb. They add strength and durability to your door frame, effectively preventing forced entry.

4. Locks

When it comes to door locks, there are a nearly endless amount to choose from. Some of the most widely used locks on entryway doors are as follows:

  • Cylinder locks function by rotating a cylinder to move the bolt. These types of locks are the most common.
  • Multi-point locks have only one handle but multiple locking points.
  • Foot bolts are a type of lock that is affixed to the base of the door and is operated by using your foot.

Each type of lock has very specific hardware, unique to their design.

Related Questions

What is interior door casing?

Interior door casing refers to the trim found around a door opening. They are considered both decorative and functional, as they enhance the look of the door while also hide the transition between the jamb and the wall.Traditional door casings are made of just tree pieces: two long trip pieces that go on either side of the door frame and then a shorter piece (the head casing) goes on top.

What is the difference between a door frame and door lining?

A door frame consists of many different elements, which includes the door lining. So, generally speaking, the main difference between a door frame and door lining is that the lining services only one purpose:  to conceal the gap between the wall and the door. On the other hand, the door frame itself is attached to the door, provides support, holds it in place, and allows it to move on its hinges.

Jessica Stone
Jessica Stone

Jessica considers herself a home improvement and design enthusiast. She grew up surrounded by constant home improvement projects and owes most of what she knows to helping her dad renovate her childhood home. Being a Los Angeles resident, Jessica spends a lot of her time looking for her next DIY project and sharing her love for home design.

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