Over the past two decades, wireless fire devices have become a highly specified solution for heritage buildings, overcoming at a stroke most of the challenges and pitfalls that these complex projects can present to fire system specifiers and installers.
While heritage and historic buildings vary hugely in terms of their age, size, purpose and construction, there are factors they all have in common, and these are the things that tend to cause sleepless nights for the people who design modern fire systems. With thick walls, multiple levels, complex layouts, hidden voids and other complications, they were never designed to accommodate modern infrastructure, such as wiring, and usually the opportunity to install new cabling that does not interfere with the fabric of the building is difficult or impossible.
Planning for all eventualities
From the complexity and structural impact of running wiring loops to the challenges presented by the building itself, heritage buildings can be a minefield for fire installers. Plans may not be as detailed or meticulous as those for more modern buildings, the quality and condition of construction is another unknown, and you may not be aware of the existence of hazardous materials like asbestos. This means it is very hard to plan for unexpected eventualities, which can lead to increased costs for construction, ‘making good’ or labour, and even more additional outlay if you need to close all or part of the building while work is taking place.
Wireless negates the need to fit long, complex wiring loops and the potential problem of delays and cost over runs caused by the building itself is also solved. As an example, a recent Hyfire project saw a school design and install take four days from start to sign off. Contrast that to an identical sister school where installation of a traditional wired system took eight months, with additional costs, disturbance and a fire watch required throughout the project.
Surveys deliver certainties
All heritage building projects should start with a detailed Fire Risk Assessment, and BS5839 states that radio integrity testing must be completed prior to the installation of radio based wireless devices. The European approved frequency, reserved exclusively for alarm signalling systems, is 868MHz-870MHz, and it is essential that equipment is third party tested to conform to EN54-25. The survey should measure the integrity of the radio transmission across the site. It also pinpoints the location of each wireless device and this gives a detailed schedule for installation, as well as delivering a fixed set capital equipment cost.
By removing the need to run wire, manage containment and fire stopping, find and fix earth and cable faults and deal with all the unknowns that digging into the structure of any building brings, more significant again in heritage sites, wireless delivers new benefits for end users, specifiers and installers. The installation can be planned in detail, including the exact devices needed and the time taken to install. The occupants of the building rarely need moving, especially important in museums, hotels and other common uses for heritage sites. Fire watches are avoided and safety and compliance are delivered quickly.
Cutting edge technology
There is no compromise on the performance a high-performance wireless fire system will deliver. The best are at least the equal of traditional wired systems and offer a number of unique benefits, however it is worth working with a wireless brand that is a specialist in high-performance fire devices, as well as wireless comms, as these are the two critical benchmarks of a dependable supplier. At Hyfire, for example, we offer ongoing fire sensor development with the current range encompassing dual optical, multi-criteria and heat detectors, input and output modules, wall and base sounders and sounder beacons, VADs and VIDs, and more niche technology such as wireless door holders.
The basic topology of the system remains the same, using standard addressable or conventional panels connected via wiring loops to wireless translators. These build up the wireless communication network on which the input and output devices sit. The extent of these high-performance systems is limited only by installation standards or the number of devices that a fire panel can control. Because standard panels are used, you can also select the performance levels required for the site, and direct connection to an alarm receiving centre or the fire brigade is an option.
Combined with the lack of associated wiring, this can significantly reduce the visual impact of the fire system, while still allowing high performance devices to be positioned for optimum protection and offering the best in false alarm rejection.
The fact that most wireless fire devices work with standard fire panels gives a number of advantages to specifiers, installers and end users. The right panel can be chosen for the right site, delivering high performance cause and effect and evacuation methodologies. Some wireless systems, like Hyfire’s, also operate in Hybrid mode, allowing wired devices to be installed side by side on the same cable loops as wireless translators. This further opens up a number of detection and input and output technologies, starting with the ability to expand or update an existing wired system with wireless devices.
In the past, wireless was often seen as a temporary alternative to wired. For example, where a fully wired system was being installed based on the existing cable network, you could use temporary wireless devices to cover each zone while the upgrade work was taking place. While this remains an option, most installers now see wireless as a preferable long-term replacement for wired systems, offering enhanced reliability and long-term reassurance to end clients.
A final advantage is that, because the installation of a wireless system is a relatively light touch process, it can be done outside of a wider refurbishment schedule, which is a significant benefit if an urgent upgrade or extension of the system is required, perhaps due to new legislation or the opening up of additional areas for public access. With no need for extensive intervention in the fabric, there is also less requirement to move or store valuable artworks and furniture, which can be an expensive and complex process in itself.
Bridging the gap
A challenge that’s not unique to historic buildings, but to which they are always prone, is the need to place devices in inaccessible places, while ensuring effective coverage and allowing for future maintenance. The good news is that with modern battery and LED technologies, wireless devices will only need to be physically accessed for test once a year, with new batteries fitted every three or more years on the best systems. Not only does this lower the lifetime cost of the fire system, it also means less upfront expense, less interruption to the daily use of the building and less need for potentially intrusive scaffolding.
Advances in battery technology and LED lighting mean wireless systems can run for many years without a battery change, a period that’s likely to extend further in the future. Battery choice, lifetime and the cost of batteries becomes a key differentiator in wireless systems. Some manufacturers use ‘off the shelf batteries’ that can be bought (if necessary) in a supermarket, others specialist batteries, which are more expensive, potentially locking in maintenance suppliers and costs. Standard off the shelf batteries also see ongoing performance, environmental and cost benefits over time as they are used in such high volumes.
A simple choice
Wireless is no longer the specialist choice, especially in heritage sites, and a large number of installers across the UK are expert in its design, installation, commissioning and maintenance, delivering wirelesses advantages widely. A wireless system can be installed in hours, not weeks, and devices can be easily moved or updated in future, allowing systems to be expanded, modified or upgraded as building use evolves and technology develops.
Installers and commissioners can guarantee installation costs and, for the organisations that manage these buildings, the upside is clear, with less disruption to visitor attractions, reduced costs and less need for intervention in the historic fabric of the building. And, with more and more of these buildings in operation year-round, wireless is the default choice to deliver an effective and optimal fire system.