The Short Version
- Most commercial insurers require a Grade 2 alarm. Consumer-grade and Grade 1 systems do not qualify.
- A bells-only alarm on a business park at 2am nobody hears. Monitored systems call a keyholder or police automatically.
- Wireless installs in one day with no cable runs, suitable for listed buildings, rented premises, and occupied sites
- Professional Grade 2 wireless systems use encrypted, supervised links, unlike consumer DIY alarms
A retail unit in Kettering gets broken into on a Wednesday night. The alarm sounds. Nobody on the business park hears it, or if they do, they assume it is a false activation and ignore it. The thieves are in and out in eight minutes. The following morning the owner reports the break-in and calls the insurer. The insurer asks for the alarm installation certificate. There is not one. The alarm was a self-installed kit from a DIY retailer.
Commercial premises run into this dispute every year. Businesses assume any alarm is better than none and that their insurer will pay a claim as long as something rang. Many find out only when the claim lands that their policy required a specific grade of system, professionally installed, with an EN 50131 certificate. The bell rang. The claim is still disputed.
The Gap Between Having an Alarm and Having the Right One
Most business owners know they need an alarm. Many buy one, install it, and consider the job done. The problem is that not all alarms are the same in the eyes of an insurer, and in an insurer’s eyes, a Grade 1 consumer device and a Grade 2 professional system are not equivalent. That gap can mean a claim pays or does not.
Commercial property insurance policies typically specify a minimum alarm standard in the policy conditions. These conditions are not always prominently displayed. Many businesses sign a policy without reading them carefully, install whatever alarm they could get quickly, and discover the gap when they make a claim.
The fix is straightforward. Before you buy any alarm, check your policy wording for “intruder alarm” or “alarm standard” and find the grade and certification your insurer requires. Then buy that system, installed by a company that can provide an EN 50131 certificate. That certificate goes to your insurer.
The most common policy condition we see in Northamptonshire commercial premises is a requirement for a Grade 2 alarm installed by a recognised company, with an installation certificate provided to the insurer within 30 days of policy inception. Check your policy before you buy, not after you claim.
Grades 1 to 4 Explained
The EN 50131 standard defines alarm grades by the level of risk they defend against and the technical requirements the system must meet.
| Grade | Risk level | Typical premises | Key requirements |
|---|---|---|---|
| Grade 1 | Low | Residential, small domestic | Basic detector coverage, no tamper monitoring. DIY systems typically fall here. |
| Grade 2 | Low to medium | Offices, retail, warehouses, small commercial | Supervised links between detectors and panel, tamper detection, anti-masking on key detectors, dual-path signalling for monitored systems. |
| Grade 3 | Medium to high | Pharmacies, cash handling, data centres, higher-value stock | Enhanced tamper monitoring, encrypted signalling, ARC monitoring required, police response capable. |
| Grade 4 | High | Financial, high-value assets, national infrastructure | Highest specification, typically only for specialist premises. |
The key difference between Grade 1 and Grade 2 is supervised links. A Grade 2 panel polls each detector continuously. If a detector stops communicating (battery failure, tamper, or fault), the panel logs it and alerts you. A Grade 1 system does not. You could have a dead detector for months and not know until something happens.
Monitored vs Bells-Only
A bells-only alarm sounds an external siren and sends a phone alert. The rest depends on someone hearing the sounder, seeing your notification, and calling the police on your behalf. On an industrial estate at 3am, that chain of events rarely completes in time to matter.
A monitored alarm connects to an Alarm Receiving Centre (ARC) that operates 24 hours a day. When your alarm triggers, the ARC receives the signal within seconds. They follow a response protocol: attempt to contact you or a nominated keyholder, verify the activation, and dispatch police or a contracted mobile patrol. The whole sequence typically completes in under 20 minutes. That sequence gives you a real chance of police attending before the premises are cleared.
ARCs can also provide video verification if your alarm links to a CCTV system. When the alarm triggers, the ARC operator views the relevant camera footage to determine whether the activation is genuine before calling police. This reduces the chance of a false alarm wasting a police response, which matters because police forces apply penalties for repeat false alarm call-outs.
The cost of monitoring is typically £15 to £30 per month depending on the ARC and response specification. For an unoccupied commercial building at 3am, monitoring is the part of the system that calls someone. At that price, it is cheap relative to what it replaces.
Wireless vs Wired
For new-build or major refurbishment projects, wired alarms remain the most straightforward option. Builders run cable before walls close, keeping installation cost low and the system complete from the outset.
For occupied buildings, rented units, listed structures, or anything where chasing cable through walls is disruptive or impossible, wireless is the better choice. Professional Grade 2 wireless systems use encrypted, frequency-hopping radio communication between detectors and the control panel. The panel polls every device continuously, so any disruption to the radio link triggers a fault alert. Jamming attempts also trigger an alert.
A wired alarm installation in an occupied commercial building takes three to five days, involves drilling, conduit, and trunking, and leaves a permanent mark on the fabric. A wireless installation on the same building takes one day and requires no structural work. For a business that rents its premises, that difference often determines whether the installation is possible at all. Most landlords will not permit wall chasing.
Battery life on professional wireless detectors runs three to five years. The panel monitors battery levels and alerts you before a replacement is needed. Annual service visits check battery status across the system and replace any devices approaching end of life.
What to Check Before You Buy
- Read your insurance policy conditions now and confirm the exact grade and certification your insurer requires before you buy
- Ask the installer whether they can provide an EN 50131 installation certificate on completion. If they cannot, find another installer.
- Confirm the panel has a minimum 12-hour battery backup in case of mains power loss
- If you want police response, check the ARC is NSI Gold accredited: police forces require this for automatic response
- Ask how the system signals if the broadband line is cut. Dual-path (IP plus cellular) is the right answer for a monitored system.
- If you have CCTV, ask whether the alarm can integrate to trigger camera recording and enable ARC video verification
Frequently Asked Questions
Book a Free Alarm Survey
We visit your premises, confirm what your insurer requires, and quote a Grade 2 system with an installation certificate. Monitored and bells-only options both available.
