The LWF Blog
Fire Safety Engineering for Design – Sprinkler Installation Planning – Part 248
August 18, 2025 10:13 amLWF’s Fire Safety Engineering blog series is written for Architects, building designers and others in the construction industry to highlight and promote discussion on all topics around fire engineering. In part 247, LWF talked about the spacing of sprinklers, including the maximum allowable distances between sprinkler heads. In part 248, we discuss drencher systems for glazing, and continue our look at the suppression of fire in atriums.
In a fire situation, water is capable of prolonging the life of glazing. External drencher systems may be used to protect buildings from the radiant heat of a fire in an adjacent building. A drencher system may also be employed to protect specific building elements, such as atriums.
Although there are no specific UK codes for drencher systems, government safety legislation such as the Regulatory Reform (Fire Safety) Order requires the implementation of suitable fire precautions to fit the identified risks and a drencher system may be the only pertinent solution. The Fire Safety (England) Regulations 2022, introduced after the Grenfell Tower Inquiry, places duties on the responsible person relating to fire doors and external walls. Finally, Approved Document B provides guidance on fire safety within buildings, including the installation of sprinkler systems, which are of the same fire safety solution group.
Although the majority of drencher systems are intended for use on the outside face of a building, there is no reason why this couldn’t be adapted for internal use to protect certain elements of a building, as a part of a fire engineered solution. Although the calculations for installation would need to be made by a fire engineering specialist, locating sprinkler heads within a metre of glazing should provide a good spray distribution and overall cooling effect to the glass.
A system to protect atriums may comprise electronic flame detectors with open sprinklers or sprayers, on a zoned deluge system. The purpose of such a system would be to replicate the speed of a sprinkler response and design density from a standard sprinkler system, but for the risk involved. However, such systems would have to be specifically designed and commissioned to suit the particular objectives of the project in question and with the full agreement of the appropriate authorities having jurisdiction.
In part 249 of LWF’s series on fire engineering we will continue to talk about the protection of atriums from fire. In the meantime, if you have any questions about this blog, or wish to discuss your own project with one of our fire engineers, please contact us.
Lawrence Webster Forrest has been working with their clients since 1986 to produce innovative and exciting building projects. If you would like further information on how LWF and fire strategies could assist you, please contact the LWF office on 0800 410 1130.
While care has been taken to ensure that information contained in LWF’s publications is true and correct at the time of publication, changes in circumstances after the time of publication may impact on the accuracy of this information.