Clickbait-y title aside, there are some neat cost saving initiatives which developers of certain new residential building developments can take advantage of with advice from their trusted fire engineer and an automatic fire sprinkler system of course!
Concession Eligibility
By definition in clause E1.5 of the National Construction Code 2019 Amendment 1 (NCC), all class 2-9 buildings in excess of 25 metres generally must be protected with automatic fire sprinklers throughout. Beyond this, there are a limited subset of buildings which require automatic fire sprinkler protection.
As residential buildings (Class 2 and 3) generally constitute the highest fire and life safety risk profile of the classifications given the potential for sleeping occupants, the code incorporated additional considerations for these classifications where the effective height is beneath 25 metres.
Specification E1.5a of the NCC applies to the following types of Class 2 and 3 buildings:
Rise in storeys of 4 or more
Effective height underneath 25 metres
Types of Sprinkler Systems
So you’ve got a building that’s within the above parameters. So what type of sprinkler system would be appropriate? The NCC has you covered there as well. You’re looking at one of the below systems:
Australian Standard 2118.1 (The most traditional type of automatic fire sprinkler system)
Australian Standard 2118.4 (sprinkler systems for residential buildings up to 4 storeys in height)
FPAA101D (automatic fire sprinkler systems connected to the domestic cold water supply)
FPAA101H (automatic fire sprinkler systems connected to fire hydrant systems)
Although any of the above systems are permitted as Deemed to Satisfy solutions under the NCC, the South Australian Fire Services (SAMFS and CFS) have historically shown preference for systems 1 and 2 and, in our experience, we’ve found greater success with negotiating Performance Solutions when these systems are in play.
Concessions on Building Design
Now to the juicy part. What are the concessions? Specification E1.5a of the NCC permits the following when either system 1 or 2 is installed (we’re ignoring what benefits systems 3 and 4 offer as they’re similar but scaled back given the limitations on those systems).
FRL of self-closing fire doors required by C3.8 or C3.11 can be reduced to —/30/30
FRL for timber non-load bearing internal walls and shafts can be reduced to —/60/60. Penetrations through these elements may be reduced to —/60/15
FRL for other non-load bearing internal walls may be reduced to —/45/45. Penetrations through these elements may be reduced to —/45/15
FRL for non-fire isolated stairways enclosed with non-load bearing construction may be reduced to —/45/45.
Maximum travel distance from the entrance doorway of a sole occupancy unit to an exit can be extended from 6 metres to 12 metres (Not applicable to residential care buildings)
The 20-metre egress travel distance allowance where the level is at the same level as road/open space may be extended to 30 metres.
Maximum distance between alternative exits can be extended from 45 metres to 60 metres.
Internal fire hydrants can be omitted provided full coverage can be achieved via an external hydrant (conditions apply).
A dry hydrant system can be used in place of an internal hydrant system (This is very controversial and caution is advised if you’d like to proceed down this pathway).
Emergency Warning and Intercommunication System (EWIS) can be omitted in residential care buildings provided the occupant warning system in place includes an override public address capability in accordance with Specification E2.2d.
The above serves as a general guide only. For further detail on exact circumstances refer to Specification E1.5a of the NCC.
Conclusion
There are some compelling reasons for residential building designers to specify automatic fire sprinkler systems all in the name of improved fire and life safety (and also some healthy flexibility in building design and budget).
Although the discussions in this blog post are not technically Performance Solutions, it’s always nice to get a fire safety engineer on your team to guide you through this process. Want to learn more? Get in touch with us.