Pre-Hung Doors vs. Slab Doors: What to Know Before You Buy

Bedrooms With Classic Hollow-Core Slab Doors

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When shopping for doors, you will encounter two entirely different types: pre-hung doors and slab doors. Generally, you will see this difference when you intend to install the door by yourself or purchase it by yourself but have someone else install it. Knowing the difference between the two categories of doors is crucial. If you purchase the wrong type of door, it may not fit your doorframe or you might encounter other difficulties with installation.

What is a Pre-Hung Door?

A pre-hung door is intended by the manufacturer to be a nearly complete package. More expensive than a slab door, a pre-hung door is a mostly self-contained unit with a frame that fits into a prepared doorway. Pre-hung doors are tightly bundled into their included frames with polyester tension packing straps and plastic spacers to prevent them for shifting or twisting during shipment.

Features that are usually included:

  • Door slab
  • Hinges
  • Frame
  • Mortises cut in the door
  • Pre-cut hole for the doorknob

Features that are usually not included:

  • Doorknob
  • Metal strike plate
  • Surface coatings such as paint or stain
  • Fasteners to attach the door to the home's doorway
  • Shims

What Is a Slab Door?

A slab door is a basic, stripped-down door that does not include a frame. It is the responsibility of the installer to attach the slab door to an existing door frame or to create an entirely new door frame.

Features that are usually included:

  • Door slab
  • Pre-cut hole for the doorknob (though often the hole is not bored)

Features that are usually not included:

  • Doorknob
  • Metal strike plate
  • Mortises
  • Surface coatings such as paint or stain
  • Fasteners to attach the door to the door frame
  • Shims

Pre-Hung Doors: Pros and Cons

Pros

  • Hinges pre-attached to the frame
  • No need to create a frame from scratch
  • No need to cut mortises

Pre-hung doors make new-construction work easy and fast. If the intended location for the door is open and exposed, you will find it easier to install a pre-hung door because it comes with its own frame. If you were to install a slab door, you would need to build the frame from scratch. While this is not a difficult task, it does add more work to your entire project.

If the existing door frame is so damaged or warped as to make it impossible to hang a slab door, it is usually easier to demolish that entire door area, frame included, and start from the beginning with a pre-hung door.

For exterior walls, it is usually better to install a pre-hung door. Pre-hung exterior doors come weather-tight off the shelf, with no need to do anything else to make them tight-fitting. By contrast, unless you are highly experienced, it can be difficult to install a tight, weatherproof exterior slab door. Pre-hung doors make this an easier process for do-it-yourselfers.

Cons

  • Not a guarantee that door will fit properly
  • Heavy and hard to manage
  • Can get twisted and bent within the frame

Pre-hung doors are heavy and hard to manage. Weighing between 50 and 100 pounds, a pre-hung interior door with a hollow core slab is the lightest pre-hung door you can buy. Even if weight is not an issue, a pre-hung door is bulky and unwieldy to move. Pre-hung exterior doors easily weigh over 100 pounds and require two strong people to move them. Also, if you have a small vehicle, transporting a pre-hung door is usually not an option.

Pre-hung door installation may seem simple but it can be difficult to get it correctly positioned. While you do not have to worry about the exacting task of hanging the slab to the frame, you still have the exacting task of fitting the pre-hung unit as a whole into the door opening. Pre-hung units, like all doors, require shimming. Even a pre-hung unit can be installed improperly so that swing and closing are impaired. Also, keep in mind that you still need to finish all of the work around it: drywall, painting, and installation of trim plus staining or painting.

Slab Doors: Pros and Cons

Pros

  • Less expensive
  • Design flexibility
  • Allows for installation of vintage doors

When saving money is of critical concern, you may want to explore the possibility of installing slab doors since they often cost much less than pre-hung door units.

Slab doors provide you with much more design flexibility than pre-hung doors. For example, if you find an antique or unique door that you want to re-purpose for your own house, you can do this with a slab door. Architectural salvage doors nearly always come in slab form, yet rarely as pre-hung units.

When installing an interior door, you may want to think about using a slab door rather than a pre-hung door unit. Interiors are more forgiving environments for imperfect installations, as weatherproofing is not an issue.

Slab doors lend themselves better to smaller installation quantities. When you are installing only one or two interior doors, you will have the extra time and patience to devote to this more difficult process.

Cons

  • Requires extensive carpentry
  • Difficult to create a smooth swing and tight fit
  • Requires mortises to be cut

Slab door installation requires a steady hand, a good eye, and plenty of practice. It is easier to install a slab door if you are doing an exact, one-for-one installation in which the new door is the same size and configuration as the old door. But if there is any variation in the door size and configuration, it will be difficult to make it hang right.

If your building skills are shaky yet you still want to install a slab door, you may wish to use a new slab rather than a recycled slab. A new slab door will be flatter and truer than a used door. Recycled slab doors usually need extra work, such as planing, sanding, and straightening.