Change or rekey · Cambridge
Deadbolt Installation
The old deadbolt has grown lazy. You turn the thumb-turn and the bolt creeps out halfway, then needs a second push with the door pulled tight.
Deadbolt Installation
In plain words
The right deadbolt for a door depends on how the door is used and where it sits. A front door that a family goes through twenty times a day needs a durable mechanism and a finish that shrugs off salt spray and sun; a side door in a laneway wants a heavy bolt and a strike that reaches the framing. Residential deadbolts carry letter grades for security, durability and finish, and heavier commercial-pattern bolts carry numbered grades, so there is a plain way to compare. The locksmith talks through those options, then fits the one you choose with the same care whichever grade it is.
How the visit goesThe back door has a deadbolt in name only: a short bolt, a thin brass strike held by two little screws, and a jamb you can flex with your palm. It was fine for a builder's showing. It is not fine for a laneway.
Cambridge
How the visit goes
Where the bolt should sit on the door
On a door with no deadbolt yet, its height is not fixed by the manufacturer but by the door in front of you. The usual spot is 140 to 150 mm above the centre of the knob, which places the bolt near the strongest part of the lock stile and keeps both locks within one comfortable reach. The locksmith checks that this height misses any glass, decorative panel, hinge line or the wood block inside an insulated door, and that the frame behind that spot is solid rather than a gap between shims. If a storm door or screen door shares the opening, the bolt's thumb-turn and cylinder have to clear it as well.
Marking and boring a fresh door
With the height agreed, the paper template is folded over the door edge and the two centres are marked: the cross bore on the face and the edge bore on the stile. A boring jig clamps over the door so the hole saw cannot wander, and the cross bore is cut from both faces to leave clean veneer or skin on each side. The edge bore is drilled with a 25 mm bit through the stile until it meets the larger hole. The locksmith then traces the bolt faceplate on the edge and chisels a shallow mortise so the plate sits flush, keeping the cut inside the lines so the edge stays sound.
A frame that now holds the bolt
Behind the new strike plate is the part of the job you cannot see and will never need to think about. The pocket has been bored deep enough for the bolt to seat fully, the plate has been let into the jamb so it sits flush, and the long screws reach through the jamb into the framing behind it. On a door that had been forced or had stripped screw holes, a full-length reinforcer may sit under the strike. If you press the jamb with your palm now, it does not flex. That stiffness is what a bolt needs to do its work, and it is the reason the installation took as long on the frame as on the door.
Deadbolt Installation
In the van
- Manufacturer's bore template
- Single-cylinder deadbolt
- Jamb reinforcer
- 25 mm auger bit
- Dry PTFE lubricant
What affects the quote
Same fees day, night or weekend
1Storm door or restricted clearance
A tight storm door, a narrow lock stile or a decorative panel at bolt height can require low-profile trim or a shifted position, which is settled and quoted at the assessment.
2Travel to the property
Distance and access are part of any call-out: a house on a suburban street and a rural property down a long road involve different driving time, and the quote says so.
3Removing and disposing of the old hardware
Some visits end with the old deadbolt and strike left with the homeowner, and others ask for it to be removed and hauled away. Taking the old hardware away adds a small amount of time and is agreed before the new deadbolt goes in.
Deadbolt Installation: questions
What is the difference between a deadbolt and the lock in my door knob?
The knob or lever holds the door shut with a spring latch: a bevelled tongue that snaps into the frame and can be pushed back by anything slid into the gap. A deadbolt is a solid rectangular bar driven by the key or thumb-turn alone, and when fully thrown it locks in place so it cannot be pressed back from the edge. The knob keeps the door closed; the deadbolt keeps it locked.
Do I need a deadbolt on the door from the garage into the house?
It is worth having. The door between an attached garage and the living space is in practice often the softest way in, since a garage door left open leaves a passage knob as the only barrier. A thumb-turn deadbolt there costs a few minutes a day and closes that gap.
How high above the knob does the deadbolt go?
The usual position is 140 to 150 mm above the centre of the knob, which lines the two locks up and keeps both within one reach. Manufacturers' templates assume that spacing, which helps a later keypad or handleset line up, though many handlesets still need their own lower hole drilled to that model's template. The height is nudged if it would land on glass, a decorative panel or a hollow spot inside an insulated door, and to make sure the frame behind it is solid.
Change or Rekey Locks
- Lock Replacement & UpgradeEvery morning the front door key needs the same little dance: push in, lift, wiggle, turn.
- Vintage Mortise Lock ServiceSomeone painted the door years ago without removing the hardware.
- Smart Lock InstallationArthritis has made the small house key hard to grip and turn, especially with gloves on in January.
Deadbolt Installation near you
One team handles every service on this page for Cambridge, so a lockout can turn into a rekey, and a rekey into a properly set deadbolt, within the same visit if you want it. Each service is described separately below, but at the door they fit together as one piece of work.