Don’t Get Burnt!
Addressing Fire Compliance in Existing Buildings
When altering, upgrading, refurbishing or remediating an existing building, fire compliance must be carefully integrated into the design and construction to comply with the New Zealand Building Code (NZBC) and Section 112 of the Building Act 2004. This requires that buildings undergoing alterations do not become less compliant with fire requirements than they were before, and, where practical, improvements need to be made to better protect occupants, those escaping from the building and enable emergency responders to attend to the fire and occupants.
Achieving this balance often involves a risk-based approach, particularly when full compliance with current fire safety standards is impractical due to cost or physical constraints. Conducting a gap analysis to assess the building’s existing level of compliance with the Building Code helps identify areas where proposed alterations can achieve compliance as near as reasonably practicable (ANARP). This approach recognises that in some alteration projects, strict adherence to current fire safety requirements may not be feasible, so solutions must be tailored to maximise fire performance within the limitations of the existing building and budget of the client.
A key aspect of this is passive fire protection, which is essential for controlling fire spread, maintaining compartmentation, and protecting escape routes. Older buildings frequently have compromised fire separations, unsealed penetrations around services, or outdated fire-rated materials. In many cases, it may not be practical to achieve full compliance, but some of the improvements that could be considered include:
Replacing non-fire-rated linings with tested fire-rated linings
Replacing noncompliant fire-resistant doors with new fire-resistant doors.
Revising locations of fire separation wall and floors
Sealing service penetrations with appropriate fire-rated systems
Upgrading emergency lighting and signage.
Upgrading the active systems such as sprinklers and heat detectors
The ANARP principle allows for practical upgrades that significantly improve fire safety without requiring a significant redesign and rebuild of the building.
Similarly, post-fire stability is crucial for the structure to remain intact long enough for safe evacuation and firefighting efforts. NZBC Clause C6 requires that a building’s primary structure maintains stability in a fire, preventing premature collapse. Many older buildings lack fire protection to structural steel or timber framing, making them vulnerable to collapse under fire conditions. However, accessing and upgrading these elements can be difficult and costly when just dealing with limited scope such as weathertightness defects on a project. Applying ANARP in these cases means holistically assessing the building’s fire performance and implementing targeted enhancements, such as:
Applying intumescent coatings or fire linings to key load-bearing members within the area of works
Protecting structural penetrations through fire separations
Incorporating additional egress improvements where structural upgrades are impractical
Another critical aspect in façade weathertightness remediation and external refurbishment projects is external spread of fire, addressed under NZBC Clause C3. Older buildings may have combustible claddings, inadequate fire breaks at inter-tenancy floors and wall, or unprotected openings that could allow fire to spread rapidly between floors or to adjacent properties. Where partial replacement of the cladding is undertaken full compliance with current façade fire resistance standards may not always be feasible, targeted upgrades can significantly improve safety, such as:
Replacing combustible materials
Installing cavity barriers and sealants
Providing fire-rated external walls where required
Evaluating these aspects as part of the design process when addressing façade weather tightness defects is critical to the ensuring that delays during consent processing and construction don’t occur.
The challenge in addressing existing buildings work is achieving compliance with the current building code. We seek to limit the extent of work and cost of addressing any gap in compliance. Upgrading passive fire protection, post-fire stability, and external fire spread protection must be done in a way that maintains the building’s overall integrity. Applying an ANARP approach allows for a risk-based evaluation, ensuring that fire safety is maximised within practical constraints.
At Agents of Architecture, we specialise in upgrading, refurbishing, remediating existing buildings and seek to balance fire safety, compliance, and budget as part of achieving the client’s vision and brief. Working closely with fire and structural engineers, and territorial authorities we integrate passive fire protection, post-fire stability, and external fire spread protection into designs to meet Building Code and Section 112 requirements while addressing the unique challenges of each project. Our expertise helps property owners, body corporates, and developers navigate complex fire safety considerations to provide solutions that are both cost effective, robust and practical.
If you’re planning an upgrade, refurbishment or remediation to an existing building and need expert guidance on fire safety compliance, get in touch with us today.