Door knobs come in several functions for different applications like closet doors, bathroom doors, and exterior doors. Here is a quick explanation of each type and where they are used.
Keyed Entry Door Knobs And Levers
Description: Entry or keyed entry knobs are usually used on exterior doors. The inside portion of a keyed entrance knob will vary according to manufacturer. On the left it shows a keyed cylinder on the outside, and a push button lock on the inside that releases when the knob is turned. Some brands of door hardware will have a turn button on the knob itself that has to be unlocked manually.
Where to use: Keyed entry door knobs are generally used on exterior doors of the home, the garage and the door between the garage and home. If any of these doors have two large holes bored, you will need to order a deadbolt as well.
Passage Door Knobs (Hall And Closet)
Description: Passage door knobs are non-locking. As shown on the left, they do not have keyed cylinders or locking buttons.
Where to used: Passage or hall/closet door knobs are used on closets, laundry rooms or other rooms that do not need to have a privacy lock.
Privacy Door Knobs (Bed And Bath)
Description: Privacy or bed/bathroom door knobs will vary according to manufacturer. On the left it shows a pin hole on the outside, and a push button lock on the inside that releases when the knob is turned. Some brands of door hardware will have a turn button on the knob itself that has to be unlocked manually and a pin hole on the end of the knob instead of the rosette as shown. Bed/bathroom knobs are unlocked using a generic key provided that is inserted into the pin hole on the rosette or knob.
Where to use: Privacy door knobs are generally used on bedrooms and baths or anywhere that privacy is needed, but an actual keyed lock is not necessary.
Description: Dummy knobs are one sided and have no working parts (fake knobs). The mounting method will vary according to manufacturer. They are usually surface mounted or mounted from behind. Dummy knobs are usually sold in pairs [dummy pair] as they are often used on sets of double doors.
Where to use: Dummy knobs are usually used on double doors. These types of doors usually have a ball catch or magnetic catch at the top to keep the door closed when not in use. Dummy door knobs are also often used on the inactive side of a French door.