Prehung doors are the most common doors for your home if you are house building. If you are remodeling, you can use prehung doors or just slab doors (without the frame).
Before heading out to shop, however, it will help to familiarize yourself with some basic terms for a prehung door:
A prehung door unit includes a door on hinges, connected to a frame, with the casing around it. These are also call “door units”. With the door pre-assembled this way, it saves loads of time in the field. In new house building, doors are always delivered and installed as prehung door units. In remodeling, sometimes only the door itself is replaced and fit into an existing frame. In that instance, only a slab door is required.
Casing is the decorative molding that surrounds the door frame. If another casing is not specified, then doors come with a small default (standard) casing. If you want something different (and you probably do), be sure to discuss this with the salesperson as it can affect the type and style of door and needs to be ordered with the door units.
The door rests in a frame, which is essentially the same thing as the jamb (it can be referred to either way). The hinges connect the door to the frame. The jamb size measures the width of the frame to fit the wall exactly-taking into account the thickness of the wall framing and wall coverings. Remember to have your builder decide the jamb size!
Panels are the raised, individual sections on some doors. When the “panels” are glass, the separate panes are called “lites”.
Paneled doors are also referred to as “stile and rail” doors. Vertical pieces on each side of the panel are known as stiles, while the horizontal sections are rails. The stiles and rails help create strength in the door and support the panels. Flush or slab doors do not have visible stiles and rails-often built within.
The threshold is a piece of wood or metal that runs across bottom of the door frame-the part that you step on when it is there. All exterior door units come standard with a threshold.
Interior doors do not come with a threshold. If a threshold is needed on the inside of a house, it is to help with transitions of flooring materials or height. It is usually made from the flooring material. For example, in a house with wood flooring in all of the rooms, there is no need for a threshold. However, if the flooring changes from tile to wood as you pass through a doorway, then a threshold softens the transition. The floor installer is responsible for ordering materials.
The transom is a piece of glass located above the door-integrated into the entire door unit. It can be operable or not. Transoms allow for more light and, possibly, air flow. Transoms add height to a door plus visual variety. If you want a transom, then a prehung door is definitely the way to go. There is a lot of door, frame and glass going on with a unit like that and prehung will cheaper and easier to install.
If you are remodeling or house building, then you will do a lot of shopping, including the doors for your home. The more you know, the easier it will be!
