If a building is defective in one area, it’s often found there are other defects, warns the NZ Institute of Building Surveyors (NZIBS).
And with recent coverage of New Zealand’s passive fire protection issues in commercial and other buildings flaring up, NZIBS past-president Trevor Jones says the importance in checking off construction standards is clear.
“Commercial buildings usually have a compliance schedule relating to important facilities and installations in the building, such as fire alarms.
“The installations covered by the compliance schedule are assessed annually, to check for fitness. This is through warrant of fitness (WoF) inspections.”
The WoF inspections cover all the installations covered by the compliance schedule, like the fire alarm, fire sprinklers and lifts, among other installations that contribute to life safety and access.
“However, during a WoF inspection, the assessment of passive fire provisions is very limited,” he says.
“If you need to exit a building in the event of a fire via a staircase, the walls around that staircase need to be constructed so they don’t allow the passage of fire and smoke into it, to provide occupiers with a route to safety for a specified period of time.
“Also, in many buildings, this staircase must provide a safe path for fire fighters into the building.”
The specified period of time is usually not less than half an hour, but it can be for an hour, or more, in specific circumstances.
“It’s calculated by reference to the type, size and height of the building and the usage of it. This will determine the time needed for people to get out of the building safely. The priority in the New Zealand building code isn’t building preservation, it’s life safety.”
According to Mr Jones, if there are faults within a building in relation to passive fire, the faults should be identified before the building work is signed off.
“There are many things that a council’s building control team can inspect when buildings are built, and this is just one of them.”
Passive fire installation work, like most other parts of construction, need a great amount of attention to get it right.
“The contractor needs to be diligent when carrying out this work too, and the council’s building control team need to be satisfied this work reaches the specified standard.”
So, between contractors and the council team, there must be assurances that an adequate standard is achieved before signing off that work.
“We are finding there are failings in passive fire installations, and this is growing.”
Also, after a new building has been checked off and the original work was built adequately, buildings then get further work done during its life.
“If that work is done without knowing what should be there, passive fire protection can be compromised.”
An example could be new building work in a hotel, some years after it was finished.
“This work includes a re-fit for new air conditioning, or heat pumps are put in. This involves making many holes through a fire wall.
“However, if nobody ensures those holes are fire and smoke sealed properly, then that could badly compromise passive fire protection against the passage of fire and smoke.”
Passive fire protection has been a longstanding issue for the Institute, which has been backing calls for greater emphasis on systems and training.
“Although it’s only been covered in the media recently, the passive fire issue is something the Institute been aware of for some time, and we are making a conscious effort to raise awareness, both within the industry and the wider public.”