Are Scaffolding Alarms Worth the Money? Can You Install A Scaffolding Alarm for under £120.00+VAT?  Yes you can……But Should You?

Installing a temporary alarm system on a scaffolding project is becoming more commonplace these days. As greater numbers of insurers are insisting that builders secure their scaffolding to prevent crime and injury law suits, there are a greater number of companies offering alarms for these applications. Unfortunately, installing an alarm is being treated by many buyers as a box ticking exercise rather than a serious consideration, deserving of their time and money and this has lead to companies supplying very poor quality equipment and service at knock down prices in order to take advantage of the box tickers. The following is a quick guide to understanding what the options are and how they perform

Cabled or wireless alarm systems?

This one is pretty obvious, Wireless beats Cabled.

Some scaffold alarm systems use a radio link between the control unit and the cameras or detectors etc. and other cheaper systems need a cable to connect the detectors or cameras to the control unit.

Cabled systems often fail due to cables being damaged during normal day to day activities on the scaffold. If not maintained properly, the cables can also cause a trip hazard. Wireless equipment generally costs a little more but the risk of damage or hazard are minimal and repair bills are less likely to land on your desk.

Mains Powered or Battery?

There are still a few companies supplying alarm systems that need a mains power supply. These tend to be systems built by the provider themselves from components designed for different applications. These are low cost options with little functionality and should really be avoided. Most modern temporary scaffold alarm systems will run for a year on their onboard batteries.

Detectors or cameras?

This is where things get a little complicated. There are Active detectors, passive detectors and cameras, or a combination.  A given installer will generally offer one type. The choices are –

Active beam detectors. 

These come in pairs and are mounted on the scaffolding at specific distances to each other (Note, these detectors were never designed for this application).

One unit will then project a laser beam to the receiver on the second unit, which is reflected back to the first. Any disruption of this beam causes a trigger and sets off the alarm.

Pros – For perimeter detection of a compound and assuming the intruder doesn’t spot the units first, these units are very good at detecting something passing between them.

Cons – The beam is only 1mm wide and the two units must be accurately aligned at all times. This makes them a poor choice for use on scaffolding as units often get knocked about by staff. Also, as the beam is very narrow, if someone climbing the scaffolding spots them, the beam is easy to avoid. The biggest problem, however, is that because the beam needs to be reflected back to a second unit,  the ends of a scaffolding run are not covered (see figure 2).

Passive detectors Can we add an image of what these things typically look like?

A passive detector is the type most commonly used at present. Passive infra-red detectors (PIRs) monitor a defined area around the unit (typically 10 – 12 meters with an arc of 90 degrees) for the infra-red (heat) energy humans, animals and vehicles put out. When a heat source is detected and is moving, the unit triggers causing an alarm

Pros – Dual optic detectors are mainly designed for external applications and are (depending on the model) immune to temperature and weather changes and small animals, making them highly effective (but not infallible) at detecting intruders in external environments.

Cons – Many of the budget alarm systems on the market use single beam PIRs which are designed for internal use. Unfortunately using single beam detectors outdoors will result in numerous false alarm activations due to temperature changes, weather changes, birds etc. etc.

Customers are advised to avoid the use of single beam detectors on any external application, not just on scaffolding.


Market leaders in the type of temporary security used on scaffolding and construction projects all supply camera based systems that send around 10 seconds of video when the detector (See types above) detects movement. These videos are not designed to be evidential quality, but to simply confirm that the alarm has been triggered by a person and not the weather or a bird etc. Using a non camera based system means that every time the alarm triggers, someone has to attend site to investigate and 9 times out of 10 it will be a false alarm.

This will end up costing the customer a great deal of wasted time going to site at all hours, or, if a response service is employed to attend site on activation, will cost the client a great deal of money in response charges. Essentially any alarm system that is installed outside and does not have video capability, is a waste of money.

Fault monitoring

One of the biggest problems with low cost systems aside from their lack of reliability of detection is that they do not communicate off site unless they are triggered. This means that neither the customer or the supplier really know if the system and all the detectors / cameras connected to it are even working most of the time. Faults are generally only discovered when a break-in occurs and the alarm does not work.

Customers are advised to check with their supplier that their system is being monitored for faults 24/ 7 and that when faults occur, they will be notified immediately and an engineer scheduled to repair the fault.

ARC (Alarm Receiving Centre) Monitoring

Typically budget priced temporary alarms are what the industry calls ‘Bells only’. This means that when an intruder is detected, all that will happen is a siren will sound. We all know how much notice is taken of alarm bells ringing…none!

Some systems do also send a limited number of people a text message informing the user of an alarm event, but that assumes the customer will hear a text message come in a 3am.

Any good temporary scaffolding alarm system will be monitored by an ARC (Alarm Receiving Centre) or the suppliers own control room. When an alarm event occurs, the ARC will personally call the list of keyholders on the account until they make contact.

There are standards for ARCs and control rooms. Customers are advised to ensure that the monitoring element of their security is NSI Gold certified, meaning they provide a first class service recognized by insurers.

Rapid response to alarm events

The majority of alarm activations occur at the start and end of the working day. Staff forget to turn the alarms off in the morning or trigger them in the evening on their way out of site. These are easy to deal with and takes a simple call to determine that it is staff. However, the real alarm events generally occur between 10pm and 3am, so quality service providers will provide a rapid response guard service who will attend the site on the customers behalf when an alarm is triggered.

These services normally cost around £10 per week for keyholding and a charge of between £30 – £60 (Depending on the part of the country) when responding to an alarm event.

Customers using an ARC monitored scaffold alarm without cameras are advised to respond to alarm events themselves, as false alarms occur more regularly than one might think and sending a guard to every one can get expensive.

Remote Camera checks

Having cameras on site, is not an end to the problem of poor detection. Building sites and often scaffolding alarm cameras get moved by staff, or obscured by materials or scaff netting. No matter how well trained the staff are, these issues occur very regularly and can have a significant impact on the efficacy of the detection system. Top notch temporary scaffolding alarms have the facility to allow the supplier / installer to dial in to the cameras at will and check that the views are not obscured and that cameras have not been moved by staff and are looking at the wrong areas. This is a rare ability but one of the most important in terms of maintaining system performance.

Customers are advised to check with their supplier to see what provision they make for moved or obscured cameras.


Contrary to popular belief there are standards for scaffolding alarms that are accepted by insurance companies. These standards are in two parts –

Standard of equipment – There are two governing bodies in the security industry, and both have issued standards that scaffolding alarms must comply with. These can be found at the following links NSI Code NCP115 and SSAIB Code Scaffolding Alarm Systems. Each code allows a minimum and an enhanced standard for such alarms.

Certification of installer – When trusting the security of your asset to a 3rd party, it is important that the supplier is certified to carry out the work to a professional standard. Unfortunately there are many security businesses that are not members of the NSI or SSAIB governing bodies and have no oversight to monitor their activities or quality of work, or insurance  cover etc.

To make matters even more complicated, scaffolding alarm installer certification by the NSI or SSAIB is separate to the normal NSI or SSAIB certification that companies installing regular alarm systems have, so just because an installer is certified as NSI or SSAIB does not mean they are certified to install scaffolding alarm systems. Customers are advised to request confirmation of certification before accepting a quotation for a scaffolding alarm system, as this may have a serious impact on potential insurance claims if the worst happens.

System Maintenance

Budget priced systems are less likely to include maintenance in the cost of the weekly hire and will charge for any site visits to maintain the equipment. Other suppliers will only charge for maintenance visits if repairing a problem caused by the client. Customers are advised to find out what site visits are chargeable and how much they will be upfront.