Historic Scotland is today’s guardian of the building and its many priceless historic treasures and today’s enemy is not armoured English knights but fire. However, fire protection in historic buildings can be a challenge, because water sprinklers can cause major water damage problems, especially with artefacts such as tapestries and paintings.
Fortunately, the gentler action of water mist fire protection is providing a solution, because the fire is smothered by wetting surfaces rather than soaking them. The minute droplets of water mist also bind with smoke particles, washing them down to floor level to drastically reduce smoke damage, one of the great secondary hazards of fire.
Historic Scotland saw this new technology as the solution for Stirling and selected Ultra SS, which has installed water mist systems in a number of historic buildings, including Blenheim Palace, to design and install the water mist system. We rose to the challenge and, in fact, the fire protection system we created for Stirling is unique, being a Low Pressure water mist system that displays High Pressure characteristics. This was what the project demanded and, Low Pressure systems being less expensive, kept us well within budget.
The opportunity to create this highly effective hybrid system came about because of the particular demands of the Stirling Project. The water for the fire suppression had to travel up a riser pipe to the top of the building to avoid damage to the fabric of the building by penetrating the walls. This in turn created the opportunity for a remarkable configuration exclusive to Stirling.
The water coming out of the riser pipe is split so as to travel through loops of smaller pipes between 15mm and 20mm in diameter. So while this is basically a low pressure system, it offers high pressure characteristics.
For a historic building like Stirling the system is ideal. To cover a room 15m by 9m, a conventional water sprinkler would require 12 nozzles, whereas a water mist system can spray up to 25 square metres via a single discreet nozzle. Sprinklers will use 5 litres of water per square metre per minute, while water mist can provide the same level of fire suppression with just 1.6 litres per minute.
At no point has the installation compromised the aesthetic and historic character of the Castle, which made the project challenging and absorbing for us and our partners in Historic Scotland’s Stirling Project:
- Morris & Spottiswood (main contractors)
- Arthur MacKay (electrical contractors)
- Stewart Kidd, consultant (Loss Prevention Consultancy).
