Prehung Interior Doors
Prehung vs Slab Door – How to Install a Prehung Door?
Prehung interior doors are made ready for easy installation, and are the popular trend for do-it-yourself (DIY) homes.
Prehung doors come hanging in their own frame. A prehung door is a complete self contained unit set, with a door slab, hinges, and outer frame that fits into a house’s prepared doorway.
- Prehung Door Standard Size
- Prehung Doors vs. Slab Doors
- Buying Prehung Interior Doors
- Prehung Exterior Doors vs Prehung Interior Doors
- How to Install a Prehung Door?

Prehung Door Standard Size
A pre-hung door typically has size of 80 inches tall and 36 inches width.
Your prehung door of this standard size should fit well into a doorway opening of 81 and 1/2 inches tall and 37 and 1/2 inch wide.
A pre-hung interior door’s thickness is an important measurement consideration when it comes to installing doorknobs and hinges.
The thinnest interior door is 1 and 3/8 inches, and the thickest is 1 and 3/4 inches. Note the thickness of 1 and 3/4 inches is about the same as a typical exterior door.
Prehung Doors vs. Slab Doors
Slab doors are quite the opposite to prehung doors, where you’re responsible for attaching the frame and mounting the hinges and other hardware of the doors.
For a house’s interior doors, prehung doors may be more expensive. When installing a prehung interior door, it usually requires less work than a slab door.
Obviously nowadays you should buy the pre-hung doors which makes installing a new door or replacing the old door much more efficient.
Buying Prehung Interior Doors
When buying prehung interior doors, set yourself to ask questions about the following items.
- Bore
- Handing
- Hardware
- Height and width
- Jamb size
- Paint or stain
- Panel configuration and profile
- Smooth or textured
- Solid or hollow
- Style of door
- Threshold
- Type of door
- Type of material
A prehung door unit should always include a door on hinges, connected to a frame, with the casing around it. The door is pre-assembled so it will save you great amount of time.
In a new house, doors are usually delivered and installed as interior prehung door units.
When remodeling a house, sometimes only the door itself is replaced, and it must be fitted into an existing frame. Then all you require is buy only a slab door.
Prehung interior doors are usually available in wood, wood composites, fiberglass or metal. The most common types are paint-grade doors and stain-grade doors.
Frames are available in paint-grade wood or wood composites, stain-grain solid, veneered wood, or metal.
Solid-core doors are heavier, quieter and more secure. Hollow-core doors are less expensive, but hollow and lighter.
When referring to a door’s size, it is the door itself, and not the overall size of the entire prehung door. For example, a a 2-6 6-8 door is 2 feet, 6 inches wide and 6 feet 8 inches high.
If the swing of the door is important for you, then look at the door opening from the outside of the room. If the hinges are on the left, then it’s a left hand door. If the hinges are on the right, then it’s a right hand door.
The jambs are the three pieces of material that make up the frame of the door, and they need to be sized to the finished depth of the door opening.
Prehung doors can be pre-bored to receive the doorknob.
If you’re installing a new pre-hung door to an empty opening, you should have few problems. But if you’re replacing an existing door, you’ll first have to remove the old door and frame. Measure the height, width and depth of the opening.
Prehung Exterior Doors vs Prehung Interior Doors
If it’s a prehung exterior door, you’ll get the sill, door bottom and the weatherstripping pre-installed.
The sill’s material may be aluminum in mill finish (silver) or anodized bronze finish. Some sills may be in wood, oak or some other hardwood.
The door bottom should be aluminum. The weatherstripping is commonly a fabric-covered foam which snaps into a slot in the frame for stopping drafts effectively.
How to Install a Prehung Door?
When installing a prehung interior door, it means that the door is already mounted onto the frame. This should save you all the work of mortising the frame and the door to receive the hinges.
In a way the above statement is correct, but it’ll take some practice to do it right.
In real practice, you’re to use more than a hammer, a chisel, and a screwdriver.
The term pre-hung isn’t as easy as it really means. The prehung door does simplify and speed up the work, but the doors and jambs should be cautiously adjusted to account for shortcomings in the doorway or wall frame. It takes patience and accuracy to fit the pre-hung door in place.
The top important aspect is that you should ensure safety all the time.
- Read and understand the door manufacturer’s installation manual and the operating instructions.
- You’ll need two people to install the door.
- Wear protective gear such as gloves, safety glasses, etc, and be cautious when handling any sharp edges or glasses.
- Don’t apply excessive force to joints, corners, or frames.
Articles on DIY Home Automation Topics
- MySmartBlinds
- Ecobee3 Lite Smart Thermostat
- Netsanity Parental Control
- Arlo Video Doorbell
- QNAP TS-251A (NAS Cloud Storage)
- Exterior Steel Doors
- French Patio Doors
- Baldwin Door Hardware