Launched in 2020, the fire research programme, Building fire-safe densified housing, facilitates the construction of more densified housing. Updates to building code fire safety clauses, acceptable solutions and verification methods will be necessary to continue to meet fire safety needs as the prevalence of densified housing in New Zealand increases. The programme will also track and inform building industry knowledge and practices to help building fire safety measures keep pace with this major shift in New Zealand construction.
Programme
The government has identified fire safety as a top priority for improvement in the building system, particularly as demand for higher-density housing increases.
The New Zealand Building Code clauses C1-C6 (protection from fire) have been identified as one of the ‘higher density 8’ (HD8) building code clauses that need updating to support higher density housing solutions. The intention will be to make changes to the building code fire safety clauses, acceptable solutions and/or verification methods that will facilitate the construction of more densified housing.
The programme goal is that by 2030, New Zealand building fire safety regulations will provide clear pathways to cost-effective, high-performing and innovative densified residential buildings. These regulations will ensure that high-density housing meets both societal and occupant fire-safety and fire-resiliency expectations.
A programme advisory group (PAG) has been established. This group provides industry feedback on the programme objectives and strategy. The programme contains current and previously funded research projects that are aligned to the programme objectives.
Key users of this research will be fire safety practitioners, designers, Building Consent Authorities, and Fire and Emergency New Zealand. Further users include MBIE BSP, who are responsible for code and compliance documents to support cost-effective and fire-safe solutions for densified housing.
Objective 1: Fire resistance
Fire resistance is a measure of the ability of building elements (such as walls, floors, beams and columns) to:
- “compartmentalise” or contain fire to localised areas of a building, and/or
- Maintain structural integrity during a fire
Compartmentalisation becomes more important as people live closer together, and structural integrity becomes more important as buildings get taller. Up until now, residential fire resistance requirements assumed traditional non-combustible building construction with limited consideration of combustible building materials. This objective explores whether our residential fire resistance settings are still fit for purpose.
Participants in the building industry who have focussed on the traditional primary residential building typology of detached dwellings face new fire safety challenges when transitioning to building densified housing. The BFSDH programme looks at ways of simplifying fire safety compliance pathways to help make it easy to deliver fire resistant construction necessary for densified residential buildings.
Projects:
Objective 2: Fire spread
Increased awareness of sustainability and embodied carbon, alongside consideration of thermal efficiency, cost and aesthetics, have driven use of more combustible materials in construction. A potential issue then is that when exposed, these materials can lead to more rapid fire spread and growth. An additional challenge is emerging trends in potential ignition sources and fuel loads such as lithium ion batteries. The BFSDH looks at how fire spread is managed on both interior and exterior residential building surfaces and how New Zealand building controls and practices can best maintain fire safety when using these materials.
Projects:
Objective 3: Emergency egress
Densified housing leads to challenges in getting people to a safe place in a fire event. We have a diverse population with varying abilities and needs for getting out of a building safely. The use of lifts for occupant egress in taller buildings is not common in New Zealand but becoming more acceptable internationally. In some high density buildings it may make sense for “refuge areas” or fire-safe places to be built into the building. This objective, led by Daniel Nilsson of the University of Canterbury, will help make sure that egress will not be a barrier to densified residential building users and that they will be confident in their ability to safely exit these buildings in a fire event.