Automist is commonly used as a direct replacement for traditional sprinklers (BS 9251). There is a legal requirement to install fire sprinklers (or an equivalent Automatic Water Fire Suppression System (AWFSS)) into all new houses, flats, apartments and other types of accommodation that stand above 11 metres tall throughout the UK, and all new homes regardless of height in Wales. Care homes, registered group homes and sheltered housing also require suppression. There is no doubt that fire suppression systems save lives, reduce property damage and reduce the cost of restoration and rehousing after a fire.
Other typical applications for Automist
Automist conforms with BS 8458. It can be used to contain the fire within the room of origin and also to provide a 'compensatory measure' when other building features do not meet one of the functional building requirements. It is commonly used for permitted variations:
- Loft conversions
Open plan arrangements on the ground floor are permissible should AWFSS be installed throughout, in conjunction with a fire-resisting partition and door at first-floor level.
- Dwelling houses with one or more storeys greater than 4.5m in height (three storeys)
Open plan arrangements on the ground floor can be achieved on the condition that AWFSS are installed throughout the property in addition to a fire-rated partition and door at the first-floor level.
- Dwelling houses with one or more storey greater than 7.5m in height (four storeys)
A second, separate protected stairwell is not required if AWFSS are fitted throughout.
- Internal Planning of Flats and Maisonettes
Flats or maisonettes with an open plan arrangement and more than one floor should have a protected stairway and AWFSS fitted. This allows escape to the shared external entrance.
- Provision of inner rooms in flats not more than 4.5 m in height.
Inner rooms are not suggested unless the use of an AWFSS is utilised throughout the entire building, along with a grade D LD1 fire detection and fire alarm system in accordance with BS 5839-6:2013.
- Open Plan Layouts
Open planned flats are permissible with a fully fitted AWFSS.
Are you allowed to use Automist in buildings over 11m?
Yes, Approved Document B includes the requirement for sprinklers in buildings over 11m. The guidance document prescribes one method of achieving the functional requirements of the building regulations but does not mean you cannot use others. BS 8458 prescribes a 45m building height limit for residential category watermist systems without additional measures:
‘The category of system should be determined by the type of building as shown in Table 1, up to a maximum height of 45 m. If the type of building is not listed in Table 1, or for buildings over 45 m, then the AHJs should be consulted to agree which type of occupancy should apply, whether additional measures are needed (see 4.6) or whether an alternative system (e.g. DD 8489-1 3) or BS EN 12845) is more appropriate.’
BS 7974 can also be used to justify the use of Automist for specific applications over and above the recommendations of the guidance documents as part of a fire engineered solution.
Keen to learn more? Explore some real-life examples where Automist was approved to meet building regulations
Disclaimer: This information is not intended to be a comprehensive guide to all of the aspects of the building regulations but rather a useful source of background information. Whilst every care has been taken to ensure that the contents of this article are correct at the time of publication, it should never be used as any form of substitution for the guidance documents. Plumis shall be under no liability whatsoever in respect to the contents of this article. It should be noted that there may be specific additional requirements dependent upon local authority building regulations and/or fire authority.