Consider a recent case from the Midlands. A warehouse manager there flagged a rear fire door that no longer shut as it should. For the security engineer who came to look, the door was not the real worry; the concern was that the fault had gone unremarked for weeks. The hinge had sagged enough to open a gap, the door had been propped for fresh air on more than one occasion, and nobody had tested the alarm sensor protecting that entrance since it went in three years before.
In the end, nothing came of it: no intrusion, no stolen stock, nothing to log. Yet a weakness of this sort is exactly what lets a casual thief succeed with little effort, and such weaknesses are far more widespread than owners generally believe.
According to the Home Office’s Commercial Victimisation Survey, nearly a third of the UK’s businesses will experience crime of one kind or another this year. The survey defines crime broadly, from theft by customers to attacks on employees, but burglary and vandalism, precisely the offences a well-designed security arrangement exists to stop, still make up a noticeable portion: each year, 8% of businesses experience a burglary or an attempt at one, and another 8% experience vandalism. Separately, ONS data for the twelve-month period ending in March 2025 show 78,707 burglaries at non-domestic buildings, covering England and Wales only. That total is far from trivial, and it is not spread evenly. Some buildings are simply easier to target than others, and the explanation tends to lie not in one glaring failure but in several small physical and procedural weaknesses that accumulate gradually.
Specialists who survey commercial sites, from a standalone shop to a warehouse spread over several buildings, find the same five warning signs appearing time after time. Each seems minor when considered separately. Viewed as a group, though, they explain precisely how vulnerable a site really is.
1. Gaps in What Your Cameras Can See
Cameras are found at most businesses. Much rarer is a layout that actually watches the spots where an intruder would attempt entry.
The typical story runs like this: a commercial CCTV system was fitted years back and then extended bit by bit as the building evolved, so newer extensions, storage spaces or parts of the car park were never properly included. Installers often discover old analogue equipment whose resolution is too poor to identify a person or a vehicle registration at any practical distance, recorders that keep footage for just a few days before recording over it, and cameras trained on the car park entrance while a loading bay to the side is left unwatched.
That is why the answer is not automatically to “install more cameras.” Sometimes moving two cameras already on site removes a blind spot; elsewhere, the better step is replacing an ageing DVR with an IP-based NVR system offering adequate retention, remote viewing and alerts triggered by motion. The key question is whether coverage corresponds to the building’s genuine weak points, rather than to wherever cameras happened to be fixed a decade ago.
2. Weak or Patchy Lighting After Dark
Lighting problems are among the easiest to solve and among the most frequently missed. Consider some familiar cases: bushes allowed to spread until they hide a dusk-to-dawn sensor; a motion-activated floodlight that failed months ago and was never reported, because nobody is on the premises at night to see it; and lights installed during construction that nobody reassessed as planting matured or the building was extended.
Darkness does more than hinder anyone checking the site by eye. It also weakens CCTV, because even a capable camera performs poorly in dim conditions unless it is given enough light, or an infrared source, suited to the range it must cover. That is why five minutes spent walking the perimeter at night teaches engineers more than people anticipate: it shows which zones are properly lit, which are lit from an unhelpful angle, and which have become dark with nobody realising.
3. Intruder Alarms Overdue for Testing and Maintenance
Seasoned installers come across intruder alarms that have gone more than a year without a service visit so often that they scarcely comment on it. The usual cycle is that a system is fitted, commissioned and then mostly ignored until a false alarm draws attention to it.
There are two reasons this is important. First, sensors deteriorate. PIR detectors can gradually lose accurate calibration, backup batteries eventually become too old to depend on, and dual-technology detectors, which pair microwave with infrared sensing, must be recalibrated from time to time if they are to function correctly. Second, and frequently the weightier point, is compliance. Under current national policy, a police response is available to systems serviced according to BS EN 50131 and connected for monitoring to an alarm receiving centre approved by NSI or SSAIB. If maintenance slips and false alarms start to accumulate, that priority may be taken away altogether, so the business must depend solely on a keyholder or a third-party responder.
In other words, routine servicing is not a formality. It is what ensures the system continues to do the work it was originally installed for.
4. Access Permissions Nobody Has Reviewed
Business owners are usually most surprised by this issue, since it seldom appears to be a security weakness until someone lists it out. Typical examples are master keys never replaced despite several waves of staff turnover, alarm codes handed round a team years back and never updated, and access fobs given to former employees that were never switched off.
Consultants frequently visit premises where the site manager honestly cannot say how many people still have a key or code that works. The manager is not to blame for this. It is simply what occurs over years of staff coming and going when no electronic access control is in place to record who entered and left, and at what time.
Today’s access control technology, whether it relies on cards, key fobs or biometric readers, provides two things that shared keys cannot: it limits entry according to time and area, and it produces an audit trail. When an incident does occur, that record is frequently what separates knowing precisely what happened from making a guess.
5. Alarms With No One Set to Respond
In practical terms, an alarm that sounds continually while no one reacts is no better than having no alarm. Yet surveys still uncover sites where the intruder alarm operates as an independent unit with no connection to any monitoring station, depending wholly on its noise to scare off an intruder or catch the attention of someone passing.
A monitored system closes this gap, provided it is linked to an alarm receiving centre and supported by a keyholder list that is kept up to date. Once a signal arrives, the ARC can confirm whether it is a genuine alert, ring keyholders in the right sequence and, if the system is eligible, ask for the police to attend. Without that connection, how quickly anyone responds comes down to luck alone: whether somebody hears the alarm, whether they know whom to contact, and whether that contact can actually be reached.
It is also worth checking keyholder lists as a task in their own right. Engineers often discover numbers that are no longer in service, staff who have left the company, or a contact order that no longer matches who could genuinely turn up quickly.
How the Pieces Fit Together
Taken one at a time, none of these five problems is disastrous. A floodlight that has grown a little dim, or a keyholder list that nobody has reviewed, will not ruin a business by itself. The difficulty is that they tend to occur together. Where lighting is poor, there is often also an outdated CCTV setup that no one upgraded to make up for it. A company careless about deactivating former staff’s fobs tends to be equally careless about servicing its alarm. The effects add up.
The benefit of a thorough site review does not come from uncovering a single striking defect. It comes from recognising a common thread across all five areas and understanding how each one affects the rest. A warehouse with first-rate CCTV but no connection to a monitored alarm still has a serious weakness. Likewise, a retail unit whose alarm is well maintained but whose camera coverage has blind spots remains open to opportunistic theft which the alarm on its own would not detect.
For an owner who spots one or two of these problems on their own premises, the logical next move is simple: arrange for a qualified professional to walk the entire site properly, instead of waiting for an incident to force the issue. The warehouse manager described at the beginning was fortunate, because the gap was discovered before anybody took advantage of it. Plenty of businesses will not have that kind of luck by chance, and with commercial burglary rates at their present level, relying on chance is not a sensible strategy.
