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GTA Lockman Mobile Locksmith Services · Toronto & GTA
Plan who opens which doors, keep the key schedule accurate, and rekey the system cleanly when a key goes missing.
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How a controlled keyway limits copying, what it costs in flexibility, and when an ordinary cylinder is enough.
Learn moreStore, label and log keys so the set still makes sense after three staff changes.
Learn moreReview what the departing employee could open, then rekey the affected cylinders and issue new keys with a record.
Learn moreOne key for everything, a key for each lock, or a master system: how to choose and what a lost key costs.
Learn moreReduce the keys you carry where cylinders and access requirements allow a suitable keyed-alike arrangement.
Learn moreDecide which internal rooms need their own access, and how that is recorded and reviewed.
Learn more
In a master-keyed system every lock has its own key, called a change key, and one or more higher-level keys also open it. A tenant's suite key opens only that suite. The property manager's master key opens every suite. Nobody needs to carry fifty keys, and nobody gets access they should not have.
The cylinders achieve this with extra pins. Each pin stack in the cylinder has more than one point where it can line up, so two differently cut keys can both turn it. The pattern of cuts across the whole building is planned on paper first, so that every key opens exactly the doors it is supposed to and no others.
Most systems are described from the top down:
A small office might need only two levels: individual office keys and one master. A school, a multi-building complex or a mixed-use property might use four. More levels give finer control, but each one uses up part of the system's capacity, so the hierarchy should match how the building is really used rather than how it might be used one day.
The key schedule is the document behind the system. It lists every door, the cylinder on it, which change key opens it, and which master levels open it too. It also records which keys were issued, to whom, and how many copies exist.
Before any cylinder is pinned, it helps to answer a few questions:
A schedule that is planned properly can run for years. One that grows door by door, without a record, ends up with keys that open things nobody intended.

Master keying is a convenience with a cost. Because each cylinder accepts more than one key, it is easier to defeat than a cylinder that accepts only one. A master key that goes missing is also far more serious than a lost suite key, because it opens every door on its level.
Three things keep that risk in proportion:
If a change key is lost, only that one door is exposed and only that cylinder needs rekeying. If a master key is lost, every lock on its level is exposed. If the grand master goes missing, the whole system is.
The response is usually one of the following:
Which one is right depends on the schedule, how long the key has been missing, and what it opened. Without an accurate schedule, the safe assumption is that more doors are affected than anyone remembers.
Most systems we see are already installed, and the work is maintenance rather than design:
Master keying suits offices, retail units with stockrooms, schools and daycares, clinics, places of worship and community halls, apartment buildings and condominiums, and landlords with several rental units. It is often combined with keyed-alike doors where a group of people genuinely need the same access, which is explained on keyed alike or keyed different.
For rooms that hold servers, records or medication, a separate key that sits outside the master system can be the better choice. See server rooms and restricted internal areas.
Have a floor plan or a simple list of doors, the people or roles who need access, and any existing keys or schedule. If the building has a mix of hardware, note which doors use deadbolts, which use lever locks and which use mortise locks, because the cylinders differ. With that information the system can be designed, quoted and installed in stages if needed. Larger commercial planning is covered on working with a commercial locksmith.
Keep reading
A change key opens one lock or one group of keyed-alike locks. A master key opens a whole group of locks, each of which also has its own change key.
A change key opens one lock or one group of keyed-alike locks. A master key opens a whole group of locks, each of which also has its own change key.
Often, if the cylinders are compatible and share a keyway. Mixed brands or very old cylinders may need replacing so the system can be pinned consistently.
Slightly, because each cylinder accepts more than one key. Restricted keyways, few high-level keys and a proper key log keep the risk proportionate.
Every lock that key opens is exposed. Usually those cylinders are rekeyed to a new master level and new master keys are issued.
The record of every door, its cylinder, which keys open it and which keys were issued to whom. It is what keeps a system accurate over time.
Yes, if the system was planned with room to grow. New cylinders are pinned to the existing schedule so current master keys open them.
Not if the system uses a restricted keyway. Copies are then made only with the system owner's authorization.
Yes. Many buildings use fobs on the main entrances and master-keyed cylinders on interior doors, with mechanical override keys for the electronic locks.
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GTA Lockman Mobile Locksmith Services is a mobile locksmith working on homes, businesses and vehicles across Toronto and the GTA, with more than 14 years in the trade. Every review is written by a customer on Google, where you can read them in full.
Areas served: Toronto, North York, Scarborough, Etobicoke, Vaughan, Richmond Hill, Markham, Stouffville, Newmarket, Mississauga, Brampton, Oakville, Milton, Halton Hills, Pickering, Ajax, Whitby, Oshawa, Uxbridge.

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