Lock Installation

What Each Door Construction Will Hold

This is the question that gets skipped, and skipping it is how good hardware ends up in a bin within a season.

A hollow-core internal door is two thin skins over a cardboard honeycomb. It will not carry a serious deadbolt however much you spend on one — the bolt has nothing to anchor into and it tears out of its housing under the first real load. On those doors a privacy latch is the honest limit.

A solid timber door will carry almost anything, which is why older housing stock is frequently easier to secure properly than newer housing at the same price. The limiting factor there is the frame rather than the leaf.

A composite door has a core with reinforcement in specific places, and an aluminium door has an internal chamber that determines both what fits and where the keep can sit in the frame. Hardware fitted outside those positions fails under load regardless of quality, which is exactly the problem our locksmith for lock replacement work is called to correct on newer doors.

The Deadbolt Question

On a door carrying only a latch, adding a deadbolt is the single best-value security improvement available anywhere on a property.

A latch holds a door closed against wind. A deadbolt holds it shut against force. The distinction matters because most forced residential entries are not sophisticated — they are somebody putting their weight against a door that only ever had a latch in it, and a latch gives at the frame rather than at the lock.

Where a door already has one, the useful question shifts to the frame: whether the keep and the surrounding timber would survive the same treatment. Reinforcing there costs less than replacing a door afterwards, and it is frequently the cheaper half of a much better outcome — which is why our locksmith for lock repair visits flag it even when nobody asked.

The doors that most often need this are not the front door. They are the scullery door, out of sight from the street, and the door from the garage into the house — where somebody who has reached the garage is already working out of view. Our residential locksmith in Sandton assessment walks both as a matter of course.

What Brings People to an Installation

Six situations covering most of this work, and what each one actually involves.

New Builds, Renovations and Handovers

Fitting to a newly built or renovated property has one clear advantage: everything can be planned as a set rather than accumulated. Which doors, which grade, whether they run on one key — all decided before anything is cut.

It also has a specific trap. Builders' cylinders fitted during construction are frequently left in place at handover, and every trade that worked on the property has held a key at some point. That is not sinister and it is entirely uncounted — the main contractor, the electricians, the plumbers, the tilers, whoever was finishing snags in the last week.

Replacing or reconfiguring at occupation is not optional. Where the hardware itself is decent, a locksmith for lock rekey is the cheaper route to the same outcome, and it is the one most new owners should be taking.

On an estate there is a second half nobody thinks about. Gate remotes, boom tags and facility cards are the estate's credentials, and nothing a locksmith does at a door affects any of them. That is a call to the managing agent — the point our locksmith for lock change in Fourways page makes about handovers generally.

What an Installation Visit Involves

Five steps, and the assessment at the start decides everything that follows. It is the part that stops good hardware being wasted.

1. Step 1

   The door is checked for square

   A lock fitted to a door that has already dropped will bind from day one. Alignment gets corrected before anything is cut or drilled.

2. Step 2

   The construction is established

   Hollow-core, solid timber, composite or aluminium. That decides what the door will hold and where the hardware can physically go.

3. Step 3

   The specification follows the door

   Grade, size and type chosen for the construction and the traffic, rather than for what happens to be in the van or on a price list.

4. Step 4

   Fitted, with the frame addressed

   Including the keep and, where needed, reinforcement that spreads load across sound timber rather than into a single screw fixing.

5. Step 5

   Tested with the door closed

   The step most often skipped elsewhere. If it needs a shove with the door shut, the keep is adjusted until no force at all is required.

The Frame Does More Work Than the Lock

Five things about the frame that decide whether an installation actually achieves anything, and that almost nobody asks about.

The keep is usually the weak point

A standard strike plate is held by two short screws into a thin section of jamb. Under a shoulder charge that is what gives, long before the lock does.

Longer screws are almost free

Screws that reach through the jamb into the structural stud behind it change what the frame will survive, and they cost a rounding error on any quote.

A box keep spreads the load

Rather than a flat plate, a box strike takes the bolt into a reinforced pocket. On a solid door it is frequently the difference that matters most.

Soft or split timber has to be dealt with

Fitting good hardware into a jamb that is already damaged achieves very little. Where the timber has gone, it gets addressed rather than covered.

On aluminium and composite, position is fixed

The keep can only go where the frame's internal chamber allows. That is a constraint to design around rather than to fight.

Fitting to a Door You Cannot Alter

A good deal of installation work is constrained by what already exists, and on older or specialist doors those constraints decide the hardware rather than the other way round.

A mortice lock sits in a pocket cut into the door edge, and that pocket was made for the lock that went into it — its depth, its height, the position of the keyhole and the distance from the door edge to the centre of that keyhole. On an older house those dimensions predate standardisation, so a modern replacement either fits them or the door has to be altered to accept it.

Altering it is possible: the pocket is enlarged, new holes are drilled and old ones are covered. It is also permanent, and on a door that is frequently better made than anything that would replace it, that is a real cost rather than a technicality.

Aluminium and composite doors have their own version of the same problem. The lock case has to suit the stile width, the handle centres have to match what is already drilled, and the multi-point mechanism has to match the existing keeps in the frame — which are not going to move.

Which is why an installation quote on an existing door cannot sensibly be given without seeing it, and why matching hardware is a skill rather than a shopping decision. See lock replacement for how that judgement is made.

Related Locksmith Services

The work that most often sits alongside an installation, or turns out to be needed instead.