How to Install an Entry Door Knob | Step-By-Step Fit

For the full breakdown, see our best Entry Door Knobs guide.

Putting in a new entry door knob is a direct afternoon job once you understand the order of operations. The whole process comes down to prep, latch, exterior half, interior half, and strike plate. Schlage’s installation guides, which cover the most common residential hardware, break the work into the same five stages every time. Before you pick up a drill, check your door’s thickness — Schlage states its knobs and levers fit doors 1 3/8 in. to 1 3/4 in. thick, and a door outside that range simply will not take the lock properly.

Measure and Mark the Door First

Start by confirming your door’s thickness with a tape measure at the edge. If it falls between 1 3/8 in. and 1 3/4 in., you’re clear to proceed. Schlage’s generic prep guide lays out the layout work: mark a centerline across the door face, down the door edge, and onto the jamb where the strike plate will sit. These three lines give you the reference points for every hole you’re about to cut.

Check the existing bore holes if you’re replacing a knob. Most entry doors already have a 2 1/8 in. cross bore and a 1 in. edge bore, so a standard replacement drops in without new drilling. If you’re starting fresh, those are the hole sizes Schlage’s template expects. The backset — the distance from the door edge to the center of the cross bore — is usually 2 3/8 in. or 2 3/4 in., and your new knob’s latch must match it.

Set the Latch Flush and Mount the Exterior Knob

Insert the latch into the edge hole with the beveled side facing the door frame. Schlage’s instructions call for drilling pilot holes and chiseling a 1 1/8 in. mortise so the latch face sits flush with the door edge. A latch that protrudes or sinks below the surface will bind against the strike plate and wear out fast.

Secure the latch with its two screws, then move to the exterior side of the door. Schlage’s quick-start guide is explicit about order: install the exterior knob first, then the interior knob while holding the outside piece in place. For an entry door, the knob half with the screw holes belongs on the interior side. Push the exterior assembly through the cross bore, align the spindle with the latch, and slide the interior half on from the other side.

Tighten Through-Bolts and Test the Action

Thread the through-bolts and tighten them gradually. Schlage’s instructions include a detail that saves you from a binding lock: push up on the knob while tightening the screws. That upward pressure keeps the latch horizontal and centered in the bore, so the mechanism moves freely once everything is snug.

Test the thumb turn and key cylinder before you close the door. The latch should extend and retract with no dragging. If it catches, loosen the through-bolts slightly, recenter the knob, and tighten again while holding it up.

Fit the Strike Plate on the Jamb

The last piece is the strike plate, and it’s where most alignment trouble shows up. Schlage’s prep guide says to mark the strike hole directly opposite the latch hole on the jamb, then drill and cut for it. Hold the plate in place, trace its outline, and chisel a shallow mortise so the plate sits flush with the jamb face.

Screw the plate in and close the door. The latch should slide into the hole and hold the door firmly with no rattling. If the latch misses or drags, loosen the strike plate screws, shift it slightly, and retest. This step is worth getting right — a misaligned strike plate is the most common cause of a door that won’t stay closed.

When you’re shopping for a replacement, look for a knob with a finish and style that match your exterior, and check the box for the same 2 3/8 in. or 2 3/4 in. backset your door uses. Our roundup of the best entry door knobs compares popular residential options side by side.

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