Sprinkler

Buildings should be designed to offer an acceptable level of fire safety and to minimise risks from heat and smoke.

The objective is to reduce to acceptable levels the potential for death or injury to the occupants of a building and others who may become involved, such as the fire and rescue service, as well as to protect contents and ensure that as much as possible of a building can continue to function after a fire. The risk to adjoining properties also needs to be considered, as well as possible environmental pollution.

The main design options for ensuring fire safety are:

Prevention: Controlling ignition and fuel sources so that fires do not start.
Communications: If ignition occurs, ensuring occupants are informed and any active fire systems are triggered.
Escape: Ensuring that occupants of buildings and surrounding areas are able to move to places of safety.
Containment: Containing fire to the smallest possible area, limiting the amount of property likely to be damaged and the threat to life safety.
Extinguishment: Ensuring that fire can be extinguished quickly and with minimum consequential damage.

Sprinklers are designed to extinguish small fires or contain growing fires until the fire and rescue service arrives.

Part B of the building regulations requires the installation of sprinklers under certain circumstances, such as new residential blocks of more than 30m in height and uncompartmented areas of shops or self storage buildings of more than 2000 square metres. They can also be used as a compensatory feature to address a specific fire hazard.

Sprinkler systems distribute water to sprinkler heads which spray water into spaces as required. They are a well-established technology and have demonstrated their reliability and effectiveness in protecting life and property over a long period.

It is thought that the oldest sprinkler system in Britain was fitted in 1812 in the Theatre Royal on Drury Lane. Traditionally, sprinkler systems have been used in commercial and industrial properties, but they are now available for a wide range of applications, including domestic buildings. More than 40 million sprinklers are fitted world-wide each year (Ref British Automatic Fire Sprinkler Association).

The British Automatic Fire Sprinkler Association suggest that losses from fires in buildings protected by sprinklers are one tenth of those in unprotected buildings.

Individual sprinklers operate when activated by their own heat detector, and then spray water onto the fire. They typically cover an area of 9 sq. m. They can be placed within occupied spaces, or in concealed spaces such as floor ducts to prevent fires from growing unnoticed.

Sprinkler systems can be:

Wet installations.
Alternate wet and dry installations.
Dry installations.
Tail-end alternate systems.
Pre-action installations.
Deluge installations.
System zones.

Sprinklers themselves can be:

Conventional and spray type sprinklers.
Ceiling, recessed and concealed type sprinklers.
Side wall type sprinklers.
Early Suppression Fast Response (ESFR) sprinklers.
Enhanced Protection Extended Coverage (EPEC) sprinklers.

According to The Impact of Automatic Sprinklers on Building Design, an independent report produced by WSP, sponsored by the Business Sprinkler Alliance (BSA), automatic sprinklers:

Typically only operate in areas where fire is present allowing adjacent rooms or areas to remain unaffected.
Reliability of discharge in the presence of fire is 98 to 99.8%, and discharge in the absence of fire is rare.
Have an 80-95% probability of being successful.
Can be designed to conceal pipes, and the availability of decorative sprinkler heads allows them to be matched with the interior of the space.

In June 2018 it was announced that the Scottish government was introducing legislation to make sprinklers compulsory in new social housing.

In March 2019 the Local Government Association (LGA) called for tougher rules on sprinklers to guarantee fire safety in high-rise buildings and care homes. Ref https://www.local.gov.uk/about/news/tougher-sprinkler-rules-needed-councils-and-fire-authorities-urge

In September 2019, following the Grenfell Tower fire, it was announced that the government was consulting on reducing the building height beyond which sprinklers are required from 30 metres to 18 metres. The consultation will run until 28 November 2019. In addition, a new Protection Board has been created to provide reassurance to residents of high-risk residential blocks that any risks are identified and acted upon. The Board will operate until a new building safety regulator is established to oversee the new regulatory regime for buildings and legislation on a new building safety regime is introduced. Ref https://www.gov.uk/government/news/sprinkler-review-for-high-rise-homes

On 2 April 2020, in response to the Building a Safer Future consultation, Housing Secretary Robert Jenrick MP announced steps to introduce mandatory sprinkler systems and consistent wayfinding signage in all new high-rise blocks of flats over 11 metres tall. The government will legislate for these reforms through the Building Safety Bill. For more information see: Government response to the Building a Safer Future consultation.

NB Planning Gateway One - Glossary, published on the Planning Portal, defines a sprinkler as a: ‘Thermosensitive device designed to react at a predetermined temperature by automatically releasing a stream of water and distributing it in a specified pattern and quantity over a designated area.’ It defines a sprinkler system as the: 'Entire means of providing sprinkler protection in premises, comprising one or more sprinkler installations, the pipework to the installations, and the water supply/supplies, except town mains and bodies of water such as lakes or canals.'