The LWF Blog
Fire Engineering Design and Risk Assessment – Fire Suppression & Sprinklers – Part 7August 10, 2017 1:30 pm
In this fire engineering design and risk assessment blog series for architects and others in the building design industry, we have been looking at fire suppression and sprinkler systems and how their use as part of a building’s fire protection plan affects the whole. In Part 6, we began looking at the potential benefits of sprinkler system installation on a design and will continue that theme in part 7.
A suitable and fully-maintained sprinkler system is likely to reduce the intensity and severity of a fire, as well as the duration. Structural elements of the building are therefore likely to maintain their integrity and load-bearing capacity for longer and so the fire-resistance levels may be reduced.
We can see advantages to a sprinkler system installation too when it comes to smoke extraction. Where a natural smoke exhaust is being replaced, the inclusion of a sprinkler system in the fire safety plan for the building means that mechanical fans may be used. The reason this becomes possible is that the extreme heat generated by hot smoke from a fire will be mitigated by the action of the sprinklers to cool the smoke. A system of this kind might be of particular use in a basement or other area without access to outside air.
The decision to include a sprinkler system in a building, at the earliest planning stage, means that certain structural elements may be changed. One such example is that assuming the sprinklers will be taking action against a fire soon after it ignites and will therefore subdue or completely put out the fire before it becomes large. It may be that the decision can be taken to reduce the number of firefighting shafts within the build.
When planning a build which is close to other constructions, a sprinkler system can control any potential fire size and therefore, reduce the radiated heat flux. This means that the building separation distance can be reduced and in terms of UK guidance, this cuts the distance required by half.
There are other benefits to be gained from the inclusion of suitable sprinkler systems in the fire protection plan for a build and designs such as large atria, shopping centres and healthcare builds can all benefit. Reference to the relevant guidances available should be made.
Sprinklers may also be placed in specific locations to enhance the fire resistance of an area of potential concern. Examples include the discharge of water over doors and openings between sprinklered and non-sprinklered areas. They can also be used to sprinkler the outside walls of buildings.
In Part 8 of this series, we will continue looking at sprinklers, but as a part of a fire engineered solution. 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 for over 25 years to produce innovative and exciting building projects. If you would like further information on how LWF and fire strategies could assist you, please contact Peter Gyere on 020 8668 8663.