At Securifix, we can provide Securifix restricted key systems for your domestic property or business including master keyed, keyed alike, keyed to differ, Evva DPS and EPS keyed and grand master keyed. Call our team on 020 8392 2233 if you need expert advice about which system is right for you.
Securifix supplies and installs restricted key systems, designed to give you full control over who holds a key and who can have one cut. Built around Evva’s patented key platforms, our systems allow a single lock suite to be configured in several ways depending on how tightly you need to manage access across a building, site, or multi-site portfolio.
Every restricted key is registered against a signed authorisation card. Once your system is in place, keys can only be duplicated by an approved supplier, and only with your written authorisation; giving you a permanent, auditable record of every key in circulation. Restricted DPS & EPS keys can now be ordered online here: Restricted Key Online Order Form
A restricted key system is a lock and key arrangement where key duplication is legally and mechanically controlled. Unlike a standard cylinder, which can be copied at any hardware counter, a restricted key can only be cut by a licensed locksmith holding a registered authorisation card in your name. This means you always know exactly how many keys exist and who holds them.
Restricted platforms also allow the underlying lock suite to be configured into different hierarchies of access — from a single key that opens one door, up to a master key that opens every door on a site. The five configurations below cover the options Securifix installs most often.
A master keyed system gives each door its own unique key, while a single master key is able to open every door on the system. Staff or tenants are issued their own individual key for day-to-day use, while a site manager, landlord, or facilities team holds the master key for full-building access.
For example, in a serviced office block each tenant might hold a key that only opens their own suite, while the building manager holds a master key that opens every suite for cleaning, maintenance, or emergency access. This keeps day-to-day access private while still giving management full oversight when it’s needed.
Master keyed systems are one of the most widely used configurations for offices, apartment blocks, schools, and multi-tenant commercial buildings, because they balance individual privacy with centralised control.
A grand master keyed system extends the master key principle across multiple buildings or sites, adding an extra tier of access above standard master keying. Individual doors are grouped into master keyed “suites” (for example, by floor or by building), each with its own master key, while a single grand master key opens every door across every suite.
This is the configuration Securifix recommends for organisations managing several sites under one ownership — for example, a facilities company responsible for multiple office buildings, or a school group with several campuses. Individual staff hold a key for their own door; a site manager holds a master key for their building; and a regional or estates manager holds the grand master key for the entire portfolio.
Because it layers several levels of access into one lock suite, a grand master keyed system needs to be carefully planned before installation, so Securifix will work with you to map out the hierarchy before cutting any keys.
A keyed alike system is configured so that every lock in the suite is opened by the same key. Unlike master keying, there is no hierarchy; every keyholder has identical, full access to every door on the system.
This configuration suits situations where several doors need to share one key for convenience, rather than needing separate, restricted access per door — for example, a row of storage units, several outbuildings on one property, or multiple entry points into a single domestic or commercial premises. Because every key is functionally identical, keyed alike systems are simplest to manage but offer no way to restrict individual doors from any keyholder.
A keyed to differ system is the opposite of keyed alike: every lock in the suite is cut to a unique combination, so no key opens any door other than its own. There is no shared or master key across the system unless one is deliberately added.
This is the standard configuration wherever doors need fully independent access — for example, individual flats in an apartment building, separate tenancies within a shared property, or any set of doors where one keyholder should never be able to access another’s space. Keyed to differ is often used as the base layer beneath a master keyed or grand master keyed system, with the master key added on top once the individual ‘differ’ keys are set.
DPS and EPS are Evva’s patented restricted key platforms, and form the high-security core of the systems Securifix installs. Because both platforms are patent-protected, key blanks are not available on the open market — keys can only be cut by an authorised Evva partner, and only against your registered authorisation card.
This closed supply chain is what makes DPS and EPS suitable for sites with a genuine security requirement, such as commercial premises, communal residential buildings, and organisations that need a verifiable, tamper-resistant record of every key issued. Additional keys can be ordered at any time through our online order form, without needing to contact us directly.
Order your DPS / EPS restricted keys online: securifix.com/ps/order-restricted-keys
A quick comparison of the five configurations covered above:
| System | Best For | Key Control |
|---|---|---|
| Master Keyed | Multiple doors, one key opens all, individual keys still work their own door | One master key holder (e.g. site manager) has full access |
| Grand Master Keyed | Multi-site or multi-building operations needing a tiered hierarchy of access | Several access levels, from single door up to whole-portfolio access |
| Keyed Alike | Multiple doors that should all open with the same single key | Every keyholder has identical, full access to all doors on the system |
| Keyed to Differ | Doors that must each have their own unique, non-interchangeable key | No key opens any door but its own |
| DPS / EPS Keyed (Evva) | High-security applications needing patented, strictly controlled key duplication | Keys can only be cut by authorised suppliers against a registered card |
Not sure which configuration fits your building? Get in touch with our team and we'll recommend the right setup before any keys are cut.
Only by a locksmith authorised by Evva, and only with your signed authorisation. This is what distinguishes a restricted key from a standard cylinder key, which can be duplicated anywhere.
Master keying gives one key access to every door within a single suite (for example, one building). Grand master keying adds a further tier on top, so one key can access multiple master keyed suites across several buildings or sites.
Yes. Most multi-tenant buildings combine keyed to differ at the individual door level with a master key layered on top for management access. Securifix will design the full hierarchy with you before installation.
Once your restricted key system is installed and registered, additional keys can be ordered directly through our online order form, without needing to contact us first.
Most single-site systems are surveyed, configured, and installed within a few working days. Grand master keyed systems spanning multiple sites take longer to plan, as the full access hierarchy needs to be agreed before any cylinders are cut.
Securifix - Home & Commercial Security Solutions
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