Change or rekey · Cambridge
Deadbolt Installation in Cambridge
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
Steel-clad and fibreglass doors, the common insulated entry doors in newer subdivisions, take a deadbolt happily as long as they are cut for it properly. The skin is thin metal or resin over a foam core, often with a wood block at lock height, so the cross bore is made with a hole saw suited to the skin, at low speed, and the edge is finished with a plate rather than a chisel mortise. Solid wood doors in older homes are cut conventionally, with care for splitting at the edge. The locksmith reads the door before drilling and picks the method that leaves a clean opening and a true-running bolt.
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.
Working on a steel-clad or fibreglass door
Insulated doors are cut with the skin in mind. A hole saw with fine teeth is run at low speed through the metal face, with the jig doing the steering so the saw does not skate on the smooth surface, and the cut is finished from the second face to keep both skins clean. Swarf is vacuumed out of the core so it cannot work into the bolt. The edge is usually a wood or composite stile inside a folded metal lip, and the bolt is finished with a drive-in collar or a plate screwed into the stile rather than a chiselled mortise. Fibreglass is scored first so the skin does not chip, then cut the same way.
A record for the home file
You should know what is on your door in plain terms, so the visit closes with a short account: the model and grade of deadbolt fitted, its finish, the backset and bore it sits in, whether the cylinder was keyed alike or set to a new key, how many keys were cut, and what was done on the frame side. For a rental, this note is useful for the landlord or building manager, who under tenancy rules is entitled to know what lock is on the unit and to hold a key. For an owner it is one line in the house file that makes the next locksmith visit, whenever it comes, a simpler conversation.
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
1Travel 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.
2Rental and building requirements
Matching a building's keyway, providing keys to a landlord or fitting a lock that a condominium corporation specifies can add hardware or bench work, each shown as its own item.
3New bore or replacement into existing holes
Boring a door that has never had a deadbolt takes more time and tooling than dropping a new bolt into holes that are already there, and the quote reflects which of the two your door needs.
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.