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Understanding Intruder Alarm Security Grades

Fire & Security, Information

Not all intruder alarms are the same…

In fact, with so many security and detection features available in modern intruder alarms, there are actually 4 different grades of alarm system in the UK.  This is based on the level of performance (Reliability, Durability and Features) that the intruder alarm offers.

Why it is important to understand the different security alarm grades.

If you are considering installing a new alarm system for your home or business (are are needing to upgrade your system) then understanding the differences in the grading system is paramount both for your building security and the requirements of insurance providers.

How does the Intruder Alarm Grades work?

Intruder alarm systems available in the UK and Europe all share a categorised grading system between 1 and 4.  The grades are based on the level of sophistication in the security system and it’s resilience against intruders who are trying to break into a premises. Grade 1 represents the lowest level of security grade and Grade 4 represents the highest.

The difference between Intruder Alarms for Homes and Businesses

Residential homes and Business Premises all share the same Intruder Alarms grading system.  Most intruder alarms installed for domestic homes are either a Grade 1 or a Grade 2 alarm system.  Larger homes and homes that are deemed high risk often have Grade 3 intruder alarm systems fitted.

Commercial premises, retail stores and other manufacturing facilities will have a Grade 2 or Grade 3 Intruder Alarm system (though many Insurance providers are now requiring Businesses to upgrade to a full Grade 3 system). While Grade 4 is the highest level of Intruder Alarm, they are generally only used by High Risk Facilities that have higher valued on site assets that need protecting.

Grade System for Security Systems for domestic and commercial properties

What if a property has a combination of graded alarm systems?

An Intruder Alarm System is only graded as high as the lowest grade components fitted in the system.  This means that if you have mostly Grade 3 components installed as part of your security system but just one Grade 2 component, the entire system would be graded as a Grade 2 Intruder Alarm System. This is because even with that one device, it create a vulnerable point in the security system that can be better exploited by intruders and as such, brings the entire security level down.

What does each Grade offer?

Grade 1

This is the lowest grade level of security and is designed to protect against the most basic of theft and intrusion acts. Grade 1 systems work well as a visual deterrent and provide adequate security against less experienced intruders and thieves who are trying to access a property.

Grade 1 systems are generally found on access doors but may not offer protection for windows (for example) and are mostly used for low risk buildings that do not contain valuable assets.

Grade 2

The next step up in Intruder Alarm Security, Grade 2 alarm systems offer an additional level of security thanks to more sophisticated technology and are seen as a more reliable solution. Grade 2 alarms offer more of a challenge for burglars who posses some level of experience and knowledge in what they are doing.  Grade 2 alarm systems protect against multiple entry points in a building and are far more suitable for higher risk homes and low risk commercial properties.  Businesses are however now being encouraged by their Insurance providers to upgrade to Grade 3 Intruder Alarms across the UK.

Grade 3

A far more sophisticated and robust system that is designed to protect properties from intruders who posses advanced knowledge and equipment for breaking and entering. Grade 3 systems MUST be comprised entirely of wired components and protect all potential access points of a building. Grade 3 Intruder Alarms  are now a standard requirement for businesses, commercial properties and high risk homes across the UK based on recommendations from the leading insurance providers in the country.

Grade 4

The highest level of Intruder Alarm Security System currently available.  Designed to protect properties against the highest level of professional, targeted attack.  Due to the sophisticated nature and higher standards to achieve the grade, Grade 4 Security Systems are only found in high risk properties that contain valuable and/or dangerous contents.

How do I know what Grade level I need

At HF Fire & Security, our Intruder Alarm Services are backed up with NSI Gold and NSI Fire Gold accreditation so that we can operate to the highest possible industry standard and guidelines across the UK. Our team can advise you on all types of security system that you should have, giving you the very best in security to suit your needs.  We can review your domestic or commercial property and provide recommendations on what products, system design and installation requirements you should have.

What Security Systems can we fit?

The security systems that we can fit are dependant on your unique property needs but we can offer:

Intruder Alarms

Offering peace of mind for those looking for a reliable and affordable intruder alarm detection system.

Fire Alarm Systems

From fire detection systems to control measures such as sprinkler systems that help to minimise the risk of fire damage to importance assets and to human life.


One of the most effective security monitoring systems available. The latest CCTV systems are fitted with night vision, comms systems and lighting systems that can work alongside intruder alarms.

Access Control Systems

Door entry systems that can use thermal control to limit access while biometric facial recognition can offer contactless ‘clock in/clock out’ functionality.

24/7 Monitoring

A complete 24/7 monitoring system for all of our Fire & Security Services for business big and small.

24/7 Call Out Service

With a maximum 4 hour Security Services Response time and 8 hour maximum Fire Services Response Time, our Security Engineers are available with fast acting telephone support to provide instant solutions to many of the most common fire and security issues that your business may encounter.

Year round maintenance and servicing

With branches across the UK, we can provide year round call out cover for intruder alarm maintenance, servicing and repairs.

Safety and security are, as with everything we do at HF, paramount. And with security and fire safety services tailored to your businesses size, complexity and bespoke requirements; we are proud to offer a 24/7 call out service as part of an extensive aftercare package that ensures your business stays secure all day, every day.

Find out more

With senior-level hands-on management from initial planning to final handover in everything from facilities management services to advanced communication systems; we our incredibly proud of the services that we can offer our customers. It all adds up to a service fully focused on protection and delivering your requirements on time and on budget – because anything else, quite simply, won’t do.

If you would like to know more about our Intruder Alarms, examples of the work we have done in this sector or if you have any questions about bespoke security services that you are looking for, please call us today on 0800 783 9480 or email We look forward to hearing from you soon.

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