How to Install a Deadbolt and Door Lever on an Entry or Interior Door
Measure backset and bore, prepare a new or existing door, fit a single-cylinder deadbolt and a matching lever, and adjust the strike so the door latches cleanly.
Most door hardware arrives ready to fit a standard bore, and most frustration comes from measuring the door wrong. Take four measurements before ordering: the door thickness, the backset from the door edge to the centre of the bore, the bore diameter and the distance between the lever bore and the deadbolt bore if both exist. Confirm those against the lock box and the job becomes assembly rather than carpentry.
Choose the function before the finish. Passage levers have no lock and suit hallways and closets. Privacy levers lock from inside with an emergency release and suit bedrooms and bathrooms. A single-cylinder deadbolt takes a key outside and a thumb-turn inside, which is the standard for exterior doors. Match finishes across the deadbolt, lever and hinges so the door reads as one decision.
On exterior doors the strike plate carries the security. Fasten it with 3 in screws that reach the wall framing behind the jamb, and do the same for the top hinge. Those two long screws do more for a door’s resistance than any grade of lock on the market.
Measure the project
Standard interior doors are 1-3/8 in and exterior doors 1-3/4 in. Most residential hardware fits both; confirm on the box.
Measure from the door edge to the centre of the bore: 2-3/8 in or 2-3/4 in. Many latches are adjustable to either.
The standard cross bore is 2-1/8 in for both levers and deadbolts, with a 1 in edge bore for the latch.
For a combined set, the distance between the two bore centres is usually 5-1/2 in. Measure it when replacing hardware on an existing door.
Stand on the outside; hinges on the left mean a left-hand door. Lever sets with a straight lever are reversible; curved levers may be handed.
Shop the material list
Choose products that match the exact room conditions and manufacturer instructions. These catalogue picks give you a practical starting point.
Have these ready
- Tape measure
- Combination square
- Drill and driver
- 2-1/8 in hole saw and 1 in spade or hole saw for a fresh bore
- Sharp 1 in chisel and hammer
- Phillips screwdriver
- Pencil and masking tape
- Utility knife
- 3 in screws for the strike and top hinge
- Door wedge or a helper
Build it in the right order
Confirm the door and hardware agree
Unbox the hardware and lay out every part. Compare the box’s thickness, backset and bore specifications with the measurements taken from the door. If the latch is adjustable, set it to the door’s backset now by twisting or sliding the latch body as the instructions show.
Mark and bore a new door
If the door has no bore, tape the paper template from the box to the door at 36 in to the lever centre and 42 to 44 in to the deadbolt centre, or match the heights of other doors in the house. Mark the face bore and the edge bore. Drill the 2-1/8 in bore from one face until the pilot breaks through, then finish from the other face to avoid tear-out. Drill the 1 in edge bore square to the door edge until it meets the cross bore.
Mortise the latch and bolt faceplates
Slide the latch into the edge bore, hold it square and trace the faceplate. Score the outline with the utility knife, then chisel a shallow mortise to the faceplate thickness, usually 1/8 in. Test-fit until the plate sits flush with the door edge. Repeat for the deadbolt. Many latches offer a drive-in collar instead; use it only if the bore is tight.
Install the lever set
Fit the exterior lever with its spindle through the latch, keeping the latch bevel facing the strike side. Hold it level and attach the interior lever and rose, tightening the two through-bolts evenly. Over-tightening binds the spring; the lever should return crisply when released.
Install the deadbolt
Slide the bolt into its edge bore with the faceplate screwed in. Insert the keyed cylinder from outside with its tailpiece through the bolt, then the thumb-turn from inside, aligning the tailpiece slot. Tighten the two mounting screws in turn. Operate the key and the thumb-turn with the door open; the bolt should throw fully with no friction.
Locate and fit the strikes
Close the door and mark where the latch and bolt centres meet the jamb, or rub pencil on the latch tip and close the door to transfer the mark. Centre the strike plates on the marks, trace them, score and chisel a mortise so they sit flush, and drill the bolt pocket at least 1 in deep. Fasten the deadbolt strike with 3 in screws into the framing.
Adjust and reinforce
If the latch rubs, file the strike opening slightly rather than moving the plate. Replace one short screw in the top hinge with a 3 in screw into the framing to resist sag. Fit the door stop where the lever would meet the wall. Test every function with the door closed, including the privacy release with a small screwdriver.
Common mistakes
Guessing the backset
A 2-3/8 in latch in a 2-3/4 in bore leaves the lever off-centre and the spindle binding. Measure first.
Drilling the face bore straight through
The hole saw blows out the paper or veneer on exit. Stop at the pilot hole and finish from the other side.
Mounting the latch bevel backwards
The flat side of the latch must face the strike or the door will not close without lifting the lever.
Using the supplied 3/4 in strike screws on an exterior door
Short screws bite only the jamb. Long screws into the framing are the security upgrade.
Over-tightening through-bolts
A crushed rose binds the spring and the lever droops. Snug is enough.
Project FAQ
Can I rekey a new deadbolt to match my other locks?
Deadbolts from the same brand and keyway can usually be rekeyed by a locksmith to one key. Mixed brands normally cannot.
Does a bathroom need a privacy lever or a deadbolt?
A privacy lever with an emergency release is the right choice; a deadbolt on a bathroom door can trap a child or someone who has fallen.
What height should the lever be?
Centre the lever at 36 in from the floor and the deadbolt 6 in above it, or match the other doors in the home for a consistent look.
Are levers reversible for left- or right-hand doors?
Straight levers are reversible. Curved or wave levers may be handed; check the box before ordering a matching set.
Do I need a locksmith for a steel entry door?
Not usually. Most steel doors come pre-bored for standard hardware. If a new bore is needed, a bi-metal hole saw and patience handle the skin.