Your Simple Guide to Different Door Knob Parts
When it comes to door knobs, every component is key
Highlights
Every part of a doorknob is crucial to its function and security.
Maintenance includes tightening loose components and replacing worn ones.
Hire a pro to replace broken door knobs to ensure that your doors remain safe.
Door knobs may seem small and unassuming, but inside they are a complex array of parts that work together to secure your home. You may already be familiar with common parts even though you don’t know them by name. Knowing different door knob parts and how they each work can help you with door knob maintenance, repair, and replacement.
What Are the Different Parts of a Door Knob and What Do They Do?
Every part of a door knob is essential to its proper functionality. Though door knobs can differ greatly in design, most consist of some form of the same basic components.
1. Knob or Lever
The most obvious component of a door knob is the knob itself. The traditional door knob design is round and twists clockwise. Some doors feature a lever instead, on which you simply pull down to open the door.
Many homeowners choose to switch out knobs when remodeling to achieve a specific look with different finishes and types of metal, wood, stone, porcelain, or even glass. Though knobs and levers vary in design and material, they all serve the same purpose as the main interface between you and the door's inner latches and locks.
2. Keyhole and Pin Cylinder
Some door knobs, especially for exterior doors, have a key-operated lock mechanism. When the proper key is inserted into the keyhole, it enters the pin cylinder. These pins vary in length and correspond to a specific pattern of grooves on a corresponding key. Match the groves to the pin lengths, and they'll move into position to lock or unlock the door.
3. Rosette or Backplate
Also visible behind the knob itself is a plate that can go by several names. A circular plate is called a rosette or rose while a rectangular one is a backplate or trim plate. This component has several functions:
Covers the hole in the door where the spindle connects the knobs on either side
Protects the door from damage
Stabilizes the knob
Provides a clean look
Rosettes and backplates mount directly into the door with screws and can be removed as needed to inspect other door knob components. The exception is with exterior door knobs, which aren't as easily disassembled from the outside.
4. Spindle
The spindle is a metal rod that runs through the door and the center of the knob mechanism. It connects both knobs to the latch, the deadbolt, and each other. The spindle rotates as you turn the knob, retracting the latch and opening the door.
A worn or damaged spindle can prevent every other component from working properly. If your spindle needs to be replaced, you can do so for just $5 to $25 on average.
5. Latch
All doors have some type of door latch that protrudes from the side of the door into a hole in the door frame. While engaged, the latch keeps the door from swinging open. When you turn the door knob or lever, the latch retracts and lets the door swing freely.
6. Deadbolt
Exterior doors may have an additional type of door lock called a deadbolt. Like a latch, the deadbolt protrudes out of the side of the door into the wall. Unlike the latch, it can only be moved by turning a key or thumb-turn switch. Deadbolts are resistant to lock picking and provide an additional layer of security.
7. Deadlatch Plunger
Another feature of exterior doors is a deadlatch plunger, a smaller bolt behind the main latch. Like the latch, it is retracted by turning the knob. However, when properly engaged, it can't be manipulated by credit cards or other thin objects commonly used by would-be intruders. Instead, deadlatch plungers require a key to open.
Deadlatch plungers are ineffective when out of alignment with the strike plate. If you hear two clicks when you close your door, that means your deadlatch plunger is out of alignment.
8. Strike Plate
The strike plate is a metal plate attached to the door frame with openings for the latch and deadbolt to slide into when the door is closed securely. It tends to have a curved edge that gently guides the latch into position.
The strike plate's purpose is to protect the door frame from wear and withstand the force of the other mechanical components. A metal plate in the door also adds another layer of protection from intruders. It may seem like a passive piece, but the strike plate is integral to the function and security of a door knob. A replacement strike plate usually costs less than $20.
9. Setting Screws
These tiny screws are found on the interior side of the door. They hold the knob or lever together with the spindle to ensure everything stays in place and functions properly. Loose setting screws can prevent a knob from having enough force to turn the spindle. If your knob is loose or wobbly, simply tighten the setting screws with a screwdriver.
10. Thumb Turn
If your door has a deadbolt or other locking mechanism separate from the main latch, it will often have a thumb turn to operate it. Turning the thumb turn retracts or extends the deadbolt to unlock or lock the door conveniently without a key. You'll only find a thumb turn on the interior side, though it may have its own pin cylinder on the exterior.
How to Maintain the Parts of a Door Knob
Incorporate door knob care into your home maintenance routine to keep your doors functioning safely and properly. Follow these tips:
Tighten screws regularly, especially on wobbly or loose door knobs.
Clean and polish door knobs to remove dirt and grime buildup.
Lubricate door handles every six months to keep small components in good shape.
Lubricate exterior knobs just before winter starts and freezing temperatures set in.
Install galvanized metal hardware outdoors to protect it from the elements.
To lubricate a door knob, spray the inside of the locking mechanism with a dry graphite spray designed for door locks. These products typically have a thin straw applicator that prevents spillage and penetrates the hardware.
DIY vs. Hiring a Pro to Repair or Replace a Door Knob
Whether or not you should attempt door knob repair or replacement on your own depends on the extent of the problem and whether you have the necessary tools and skills.
For example, tightening the screws on loose knobs is a simple DIY task that any homeowner can handle. However, replacing locks is more complex, and mistakes can lead to even higher material costs down the line.
Hiring a reputable local door repair company will save you time, maintain your home insurance coverage, and provide you with a warranty. When it comes to the cost of professional door repairs, expect to pay $30 to $50 per door knob.