When shopping for doors, you will encounter two entirely different types: slab doors and pre-hung doors. What does each type of door do for your house and how are they different?
The Basics of Slab and Pre-Hung Doors
When you purchase a door, you have a choice between two types: slab doors or pre-hung doors. A slab door is the most basic, stripped down kind of door. It is just a door and nothing else. It usually comes without hinges, door knobs, or most importantly, a surrounding frame. It is up to the buyer to attach the slab door to an existing door frame or to create an entirely new door frame. Mortises (the indents on the door where the hinges rest) are usually not pre-cut. It is up to the buyer to cut mortises.
By sharp contrast, a pre-hung door is a nearly complete package. More expensive than a slab door, a pre-hung door comes already hanging in its own frame. It is a nearly self-contained unit, consisting of a door slab, hinges, and an outer frame that fits into a prepared doorway. Several items are not included, such as the outer trim that blends the door in with the wall, doorknob, and the metal strike plate.
Reasons for Pre-Hung Doors
- In new-construction building, where a door is first being installed (as opposed to a replacement door), it is usually advantageous to install a pre-hung door. 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 other than to install them properly. 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 (though not easy) process for do-it-yourselfers.
Reasons Not to Install Pre-Hung Doors
- Pre-hung doors are exceedingly 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 a bulky product to move around. Pre-hung exterior doors easily weigh over 100 pounds and need two strong people to move them. Also, if you have a small vehicle, transporting a pre-hung door is nearly impossible.
- 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 trim staining or painting.
Reasons for Slab 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 less-than-perfect installations, as weatherproofing is not an issue.
- Slab doors lend themselves 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.
Reasons Not to Install Slab Doors
- 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 (a situation when the new door is the same size and configuration as the old door). But if there is any variation in door size and configuration, it will be difficult to make it hang right.
- When you are installing an exterior door, you may wish to either install a pre-hung unit or hire an experienced carpenter to install your slab door.
- 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.