Sprinklers – An essential tool
in fire engineering design
Jon Pagan MA(Cantab) CEng MIFireE
Director of Fire Engineering
International Fire Consultants Ltd
www.ifcgroup.com
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Introduction
• Fire engineering more widely used in
construction
• Especially in the UK
• Fire engineers use all available methods to
help design
– Sprinklers, smoke ventilation, water mist, fire
alarm enhancements etc
• Sprinklers are one of the most beneficial tools
to assist fire engineering analyses
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Restrictions on use of sprinklers
• Why aren’t sprinklers used more?
• Question of whether sprinklers are needed
arises on most projects
• Developers’ response is usually “Can we avoid
sprinklers?”
• WHY?
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Cost
Appearances (visible sprinkler heads)
Space for tanks/pumps
Concerns re water damage
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Cost issues
• Need for large tanks, pumps, power supplies,
distribution pipework
• Highly expensive
• Loss of space for tank/pump room
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Appearance
• Architects don’t like to see sprinkler heads
• Concealed sprinkler heads can usually be
used
– Partially mitigates the concerns
– But architects would still rather avoid
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Concerns re water damage
• Public perception is of major risk
• What public see in films etc is:
– Activated by small amounts of smoke
– Sets off all sprinklers in building
• Clearly completely wrong
• But public perception is usually negative
• Very few people would pay more for a
building that is sprinklered
• So developers see very little benefits in
sprinklers
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Insurance
• Insurers usually recommend sprinklers
• But usually reduced insurance premiums not
enough to justify sprinklers
• Exceptions are high fire risk buildings, e.g.
waste recycling
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Common reasons for installing
sprinklers
1 – Necessary to comply with guide/code
• Height
• Compartment size
• Etc
2 – Needed for insurance
• Only really for high fire risk buildings such as waste
recycling, some schools etc
3 – As part of fire engineering justification
4 – Other reasons?
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Fire engineering
• Fire safety design guides available for all
types of buildings
• Sometimes hard/impossible to comply with
certain issues
• Fire engineering approaches can be used to
justify variations
– Smoke modelling, evacuation analyses, structural
fire engineering, radiation analyses etc
– Justified case-by-case
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Harveys Warehouse,
Lutterworth
• Existing large warehouse in Magna Park
• Harveys planned to use it as main distribution
base
• Fitout included:
– large multi-level mezzanine decks in 2 locations
– High bay racking throughout rest of building
• Original design included sprinkler system at
roof level fed from site-wide supply system
• IFC appointed to carry out fire safety design
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Problems to deal with
• Main issues were:
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High fire load present
Long travel distances in main warehouse areas
Long travel distances in mezzanine areas
Long fire brigade access distances
Need for fire protection to mezzanine structure?
Smoke ventilation issues
Existing sprinkler system supply adequate?
• Client queried whether we can avoid
sprinklers?
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Existing 2-storey
office
Future fit-out
area
New high bay
racking
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New 4-storey
mezzanine
Mezzanine areas
• Sprinkler system
– Sprinklers needed throughout the mezzanine
– Reviewed design and specification of goods to be
stored
– Checked flow rates and sprinkler design criteria
needed
– Checked that the existing supply was adequate
– Put together technical specification for tender
– Helped client review tenders
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Unprotected
Protected
(open) stairs
(enclosed) stairs
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Results
• Sprinklers were:
– Expensive
– Introduce risk of water damage
– Affected the design
• But allowed:
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Travel distance extensions
Large multi-level compartment size
No fire protection to mezzanine structure
No smoke ventilation
Improved insurance premiums
Building control/fire officer approval
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Residential sprinklers
• Relatively new design standard
BS9251
• Installations are inexpensive
• Clients still have concerns
about:
– Cost
– False alarm water damage
– Appearance
• But in the end it usually comes
down to either “it’s required” or
money
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Residential sprinklers
• Cost of installation low, so only need modest
savings to justify
• QS costing techniques at early stage very
rough
– So can be hard to prove the savings
• Open plan flats:
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Improved sale value (debatable)
Reduced number of fire doors
Cost of sprinklers roughly = 1 fire door
Sometimes can reduce the floor area
• Sprinklers in more new buildings than ever
before
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Summary
• Fire engineering will regularly use sprinklers
to help design/analysis
• Highly beneficial and significantly improves
safety
• But the industry still has to address client
reservations/concerns
– Cost, appearance, risk of false alarms
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