Design, Construction and Seismic Performance of Non- Structural Elements in New Zealand

Abstract

The performance of buildings in recent New Zealand earthquakes (Canterbury, Seddon and Kaikōura), delivered stark lessons on seismic resilience. Most of our buildings, with a few notable exceptions, performed as our Codes intended them to, that is, to safeguard people from injury. Many buildings only suffered minor structural damage but were unable to be reused and occupied for significant periods of time due to the damage and failure of non-structural elements. This resulted in substantial economic losses and major disruptions to our businesses and communities. Research has attributed the damage to poor overall design coordination, inadequate or lack of seismic restraints for non-structural elements and insufficient clearances between building components to cater for the interaction of non-structural elements under seismic actions. Investigations have found a clear connection between the poor performance of non-structural elements and the issues causing pain in the industry (procurement methods, risk aversion, the lack of clear understanding of design and inspection responsibility and the need for better alignment of the design codes to enable a consistent integrated design approach). The challenge to improve the seismic performance of non-structural elements in New Zealand is a complex one that cuts across a diverse construction industry. Adopting the key steps as recommended in this paper is expected to have significant co-benefits to the New Zealand construction industry, with improvements in productivity alongside reductions in costs and waste, as the rework which plagues the industry decreases.

Full text

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Design, Construction and Seismic Performance of Non-
Structural Elements in New Zealand
Jan M. Stanway(1), Tim J. Sullivan(2), Rajesh P. Dhakal(3)
(1) Principal Structural Engineer, WSP, Christchurch, New Zealand
(2) Professor, University of Canterbury, Christchurch, New Zealand
(3) Professor, University of Canterbury, Christchurch, New Zealand
Abstract
The performance of buildings in recent New Zealand
earthquakes (Canterbury, Seddon and Kaikōura), delivered
stark lessons on seismic resilience. Most of our buildings, with
a few notable exceptions, performed as our Codes intended
them to, that is, to safeguard people from injury. Many
buildings only suffered minor structural damage but were
unable to be reused and occupied for significant periods of
time due to the damage and failure of non-structural elements.
This resulted in substantial economic losses and major
disruptions to our businesses and communities.
Research has attributed the damage to poor overall design
coordination, inadequate or lack of seismic restraints for non-
structural elements and insufficient clearances between
building components to cater for the interaction of non-
structural elements under seismic actions.
Investigations have found a clear connection between the poor
performance of non-structural elements and the issues causing
pain in the industry (procurement methods, risk aversion, the
lack of clear understanding of design and inspection
responsibility and the need for better alignment of the design
codes to enable a consistent integrated design approach). The
challenge to improve the seismic performance of non-
structural elements in New Zealand is a complex one that cuts
across a diverse construction industry.
Adopting the key steps as recommended in this paper is
expected to have significant co-benefits to the New Zealand
construction industry, with improvements in productivity
alongside reductions in costs and waste, as the rework which
plagues the industry decreases.
Introduction
Non-structural elements generally can be classified into three
broad categories:
• Architectural elements, such as exterior cladding and
glazing, ornamentations, ceilings, interior partitions
and stairs,
• Building services components and equipment,
including air conditioning equipment, ducts,
pipework, cabling and cable trays, sprinklers, lifts,
escalators, pumps, plant items and emergency
generators,
• Building contents, such as movable furniture,
bookshelves, computers and entertainment
equipment.
The Architectural elements and Building services (which
constitute the majority of drift and acceleration sensitive non-
structural elements) can cost between four and seven times of
the total structural system cost in most buildings (Khakurel et
al, 2020), and their repair cost can dominate the total repair
cost of buildings after major earthquake (Bradley et a 2009).
Non-structural elements suffered extensive damage in the
Canterbury (Dhakal 2010, Dhakal et al 2011), Seddon and
Kaikoura earthquakes (Baird & Ferner 2017). Figures 1 and 2
illustrate samples of the observed damage.
Figure 1: Illustrating damage to non-structural elements
observed in the Canterbury earthquakes (from Dhakal,
2010)

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The cost to repair the material damage and the value of the
business interruption due to poor performance of non-
structural elements in these earthquakes was substantial,
although difficult to quantify due to the repair costs often not
being publicly documented by insurers and repairs which cost
less than the insurance excess completed by building owners
and not captured in overall losses. Research showed that
Business Interruption costs were significantly higher than
material damage repair costs in recent New Zealand
earthquakes (Stanway & Curtain 2017). It is now recognized
that damage to non-structural elements is a bigger issue than
the damage to primary structure.
The damage to non-structural elements was greater than
expected by building owners, tenants/users and insurers. This
was especially the case for buildings which suffered significant
damage despite being subjected to shaking significantly lower
than the ultimate limit state earthquake (defined as an
earthquake with a 10% probability of exceedance in 50 years).
Verbally the insurance industry has advised that numerous
buildings suffered major insurance claims as a result of
damage to non-structural elements but were only subjected to
seismic shaking around a 1 in 100-year event (defined as an
earthquake with a 40% probability of exceedance in 50 years).
The performance of our buildings caused many to pause and
consider if current design and construction practices are
delivering the buildings that meet the needs of our
communities. Do we have the right balance between designing
to preserve life in extreme, infrequent events versus designing
for lesser more frequent events that enable continued
functional use of the buildings in a way that meets the needs
and expectations of our communities?
To better understand the underlying reasons for the poor
compliance and seismic performance of non-structural
elements in New Zealand, a strategic review of the New
Zealand construction industry in relation to non-structural
elements in both new and existing buildings was completed in
2020 (Building Innovation Partnership, 2020).
The review was based on literature research, university
research, post-earthquake observations and industry
workshops which included participants from a wide cross
section of the construction industry (owners, regulators,
project managers, quantity surveyors, consultants, contractors
and specialist sub-contractors).
Current Industry Challenges
The New Zealand construction industry is challenged at its
heart by risk avoidance. Contracts and procurement
methodologies transfer risk from the asset owner to the
construction team.
There appears to be a lack of appreciation by the asset owners
and project managers of the value of collectively managing the
risk and responsibility for the design, coordination and
construction of non-structural elements and their seismic
restraints.
Current procurement methods (often lowest price conforming)
have significant implications for construction teams, with
additional risks assigned to the construction teams through the
expectation to provide a fixed price, without tags, based on
incomplete documentation where the detailed design and
coordination for non-structural elements has not been
undertaken. It often follows that when the construction teams
complete the design and coordination of the non-structural
elements, wider issues are uncovered. For example, it is not
uncommon to find that there is insufficient room to install code
compliant non-structural elements and seismic restraints
within the space provided within the building envelope.
Changes of this magnitude are too difficult to make during the
construction phase and therefore lead to compromises in
compliance and have the potential to lower the seismic
performance expected.
Contractors have reported (Building Innovation Partnership,
2020) that they want to construct and install fully resolved
designs but they are currently taking on design risk for seismic
elements that is difficult to accurately assess and price at
tender. They noted it is common for items to need to be
reconfigured 3+ times to get the installation right.
To be competitive in a market driven by risk transfer and
lowest cost, many subcontractors try to manage the cost risk
by choosing the easiest and cheapest support points and
reticulation routes without due consideration of the potential
significant effects for other subcontractors or other elements of
the building. An uncoordinated installation by one
Figure 2: Illustrating exterior damage to non-structural
elements observed in the Kaikoura earthquake (from Radio
NZ/Susie Ferguson)

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subcontractor can change a compliant installation from another
subcontractor into a non-compliant one.
Industry participants at workshops noted that some contractors
and sub-contractors are using the fact that no independent
inspection occurs to check the use of inferior products (for
example, fixings that are not approved for seismic loading), or
not installing seismic braces in accordance with the design and
standards and reducing their fees accordingly to win the work.
They also noted that without full coordination, product
substitutions are often offered to the project team with an
associated cost saving. The substitution is approved on the
basis of the cost saving. However, in practice it is common that
the knock-on effects of the change in the equipment/product to
other building elements is far reaching and the costs to adjust
other components to achieve clearances and not compromise
the seismic performance of other components results in
variations and project delays that far outweigh the cost saving
originally offered.
Currently, the design, coordination and construction of non-
structural elements and their seismic restraints rely, in the most
part, on self-regulation of the industry. Research (Building
Innovation Partnership, 2020) has indicated that self-
regulation is not working, and New Zealand is falling well
short of the seismic performance expected of non-structural
elements in the new building stock.
There is currently a lack of coordination during the design and
construction and a lack of on-site observation, by all parties, to
verify that what is required, has been constructed. Figures 3, 4
and 5 show examples from a recent building where numerous
non-compliance issues were found towards the end of
construction.
Figure 3: Insufficient clearance between gravity hanger and pipe,
and gravity support for pipe hung off hanger for cable tray above
Figure 4: Ceiling hangers run through cable tray
Figure 5: Clash of pipe with insulated pipe and cable tray
In addition to the coordination and installation issues,
university research (Pourali et al 2014, Stanway et al 2018) has
demonstrated significant gaps in technical knowledge both
nationally and internationally, especially with regard to how
various non-structural elements respond to seismic
accelerations and building drifts and the interaction, impact
and damage of various building components during seismic
events. Since the 2010-11 Canterbury earthquake sequence,
NZ engineers have become increasingly aware of the
importance of the seismic design of non-structural elements
and multiple research projects have led to significant progress
in understanding and improving seismic performance of non-
structural elements and contents (Dhakal et al 2014, 2016a,
2016b, 2019, Pourali et al 2017, Yeow et al 2018, Khakurel et
al 2019, Mulligan et al 2020, Arifin et al 2020). The New
Zealand Seismic Assessment Guidelines (albeit not capturing
the essence of all recent research findings) have also been
developed for practicing engineers to estimate seismic
capacity of non-structural elements in existing buildings
(NZSEE, 2017).

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Sullivan et al. (2013) and others have demonstrated that
international standards provide poor prediction of floor
spectral demands, particularly for non-structural elements
characterized by low levels of damping. As an example, the
left side of Figure 6 shows that the acceleration demands on
non-structural elements characterized by 2% damping atop an
8-storey RC wall building are likely to be underestimated by a
factor of around three when the period of the component
corresponds to the 2nd mode period of the building (0.5seconds
for the case shown).
Figure 6: Comparison of predicted floor acceleration response
spectra at top level of an 8-storey RC wall building (from Sullivan
et al. 2013)
Figure 7 reminds us that the amplification of acceleration
demands felt by components is not new, with Biggs (1971)
reporting high amplification of demands on equipment (with
0.5% damping) almost 50 years ago.
Figure 7: Dynamic amplification factors (ratio of acceleration
demand on a component to peak floor acceleration demand)
from Biggs (1971)
Currently, ductility reduction factors are included in some
codes to allow reduction of elastic acceleration demands to
design levels that allow for some non-linear response of the
component. However, it would appear that there is little
evidence from research or in-situ observations that the ductility
reduction factors included in codes are appropriate.
Passive fire elements have had little research to test the fire-
resistance and smoke rating of passive fire resistance products
following an earthquake.
The current issues facing the construction industry are not the
fault of the contracting teams. Without appropriate scope
definition, risk allocation, project budget and programme to
allow full coordination of all non-structural elements from
project inception, the outcome is inherently compromised.
The result is that many recently constructed buildings have
Code Compliance Certificates, but feedback from industry
(Building Innovation Partnership, 2020) and research
(Geldenhuys et al, 2016) suggest that many of the non-
structural elements in these buildings do not meet the
requirements of the New Zealand Building Code.
The Vision for the Future
What could our industry look like when the seismic
performance of non-structural elements is recognized as a key
component to overall building and community resilience?
This would require fair and appropriate risk allocation, clear
responsibilities and fully coordinated design and construction
with procurement methods that support these outcomes.
Even greater improvements in resilience would be achieved if
we adopted enhanced design requirements for non-structural
elements.
The vision is that following a major earthquake non-structural
elements would perform as per the design intent, and that the
process to design and install the non-structural elements has
been undertaken with fair and appropriate risk allocation and
compensation.
Recommended Steps to Improve Compliance and
Seismic Performance of Non-Structural Elements
Research by Stanway & Curtain (2017) and the Building
Innovation Partnership (2020), has shown that the poor
performance of non-structural elements is a system failure of
the New Zealand construction industry.
The New Zealand construction industry, from the regulator
(MBIE), building owners, designers, and contractors need to
work together if we are going to achieve the productivity and

5
performance outcomes for our future building stock, that meets
the expectations of our industry, owners and wider community.
The issues facing the construction industry won’t go away
simply by tinkering with codes, demanding cheaper costs or
scattering enforcement or resilience through random projects.
Taking action will challenge the industry. Seven key steps are
recommended to deliver more resilient and productive
outcomes. Some of these steps will be superseded by future
steps.
1. Development of training, guidance documentation,
and a Code of Practice.
2. Define roles and responsibilities of different
stakeholders.
3. Carry out research and testing to enhance our
understanding and design solutions.
4. Develop a seismic classification system and a two-
tier compliance pathway to be included in the Code
of Practice.
5. Introduce an independent quality provider and
certification body for non-structural elements.
6. Update standards to provide a single source document
for the seismic design and performance requirements
of non-structural elements, including enhancements
to design based on outcomes from research and
testing.
7. Introduce a new clause in the New Zealand Building
Code specifically for non-structural elements and
systems.
The following sections summarize each of the recommended
steps.
Training, Guidance Documentation and a Code of
Practice
Industry training is developed and offered widely to all parties
including clients, councils, consultants, project managers and
contractors. The training would provide the technical how and
why for consultants and contractors, along with training for
quantity surveyors, insurers and owners on what the new
system is and what it delivers. Training would continue to be
developed and offered to industry in parallel with future steps
and developments.
In the future, all important aspects of seismic performance of
non-structural elements would be well understood in the
industry, similar to fire and acoustic disciplines. Specialist
designers and contractors would be widely available to provide
advice and share their knowledge to the industry and junior
colleagues.
In consultation with stakeholders it is recommended that a
suite of industry guidance documentation is developed
including:
• Overarching Principles. This document would
provide the high-level principles and performance
requirements to achieve functional recovery of
buildings following various seismic events.
Guidance will likely include recommendations for
earthquake return periods, acceleration and drift
limits to achieve various performance states, i) no
damage, ii) controlled, repairable damage, and iii)
collapse prevention. This guidance document would
benefit designers, contractors, building owners and
tenants as it will provide, the performance
requirements of the building, which will enable better
understanding of the risk of loss of function of
buildings in moderate earthquakes.
The document will also define the type of work and
upgrades to existing non-structural element systems
that would constitute an alteration to the building, in
accordance with section 112 of the New Zealand
Building Act.
• Procurement. There is a need for a guidance
document which describes the various procurement
methodologies along with the risk allocation and the
resulting risk to building owner for each procurement
method. Recommended procurement methods would
be described as well as a discussion on procurement
methods that are not recommended.
• Code of Practice. This document will reference the
Overarching Principles document, include
compliance pathways, the requirements for
coordination, a seismic classification system for non-
structural elements, which is still to be developed, and
individual chapters for various non-structural
elements. The proposed seismic classification system
for non-structural elements is described in more detail
in a later section of this paper. The coordination
process and design development for each design
phase (concept, preliminary, developed, detailed and
construction) would be documented to provide
consistency of approach through the industry and
support brief development and procurement of
consultants and contractors.
The technical design for each component would
include recommended standard details and anchor
types (Del Rey Castillo, 2019) for support and
seismic restraint of non-structural elements into
various substrates.

6
The Code of Practice would likely be the first step
towards a new Verification Method specifically for
non-structural elements and systems.
• Construction Monitoring and Inspection. There is
also a need for a guidance document for the
construction monitoring and inspection of non-
structural elements and systems. It would ideally
have two sections as follows:
- Inspection and assessment of existing non-
structural elements, seismic restraint systems
provided and clearances to other building
components. A document specific to existing
buildings would provide a consistent approach
for assessment and reporting of issues and risks
in existing building.
- Guidance on the inspection of new installations
of non-structural elements for consultants,
contractors and third party independent
inspectors.
Roles and Responsibilities
Working together with the wider construction industry the
roles and responsibilities of owners, tenants, architects,
building services engineers, structural engineers, non-
structural seismic engineers, contractors and sub-contractors
will be defined for non-structural elements and systems. This
is important for procurement, brief development and the
design and installation process.
Definition of responsibilities will support more effective
construction monitoring which is expected to improve
compliance and reduce the incidences of unapproved product
substitutions being used.
Research and Testing
Research into the seismic performance of non-structural
elements over the past decade in New Zealand has identified a
number of areas in which changes should be made. Gaps have
been identified in the understanding of the seismic
performance of different types of non-structural elements in
new and existing buildings (MacRae et al 2012, Pourali et al
2014, Muhammad et al 2020). In response to this a seismic
rating system for non-structural elements is proposed which
will classify non-structural element systems according to their
drift and acceleration capacity (Sullivan et al. 2020).
Further research will be undertaken to better understand and
quantify how various non-structural elements respond and
interact with other building components during seismic events.
The research will inform recommendations for changes to
design practice and effective retrofit of deficient non-structural
systems in existing buildings.
Seismic Classification System for Non-Structural
Elements and Two-tier Compliance Pathway
Current design standards generally have limited information
for the design and checking of the seismic capacity of non-
structural elements. There is an increasing body of evidence
that a number of drift limits specified in standards and codes
will not lead to the intended design outcomes (Muhammad et
al 2020, Sullivan et al., 2020).
The likelihood of exceeding the drift and acceleration damage
states (no damage, functional recovery and collapse
prevention) for non-structural elements depends not only on
the intensity of ground motion but also heavily on the selected
primary structural system. To achieve good seismic
performance of non-structural elements, the structural
engineer needs to assess the implications of the choice of
primary structure on the selection of non-structural elements
and systems and effectively communicate the drift and
acceleration demands they anticipate for their specific building
to any subcontractors responsible for design and installation of
non-structural elements. The proposed seismic classification
system for non-structural elements (Sullivan et al., 2020) is
intended to facilitate the structural design, non-structural
design and communication process.
The seismic classification system would classify specific types
of non-structural element according to their critical drift (or
acceleration) capacity established relative to defined limit
states, a) No Damage, b) Life Safety. A third intermediary
limit state may also be appropriate for certain projects, being
c) Damage Control limit state. It is recognized that for many
non-structural elements there may be little, if any, difference
in practice between the design and detailing for no damage
compared to a damage control limit state.
Tables 1 and 2 below propose tentative values of drift and peak
floor acceleration (PFA) respectively for different
classification categories of non-structural elements.
Table 1: Tentative drive values proposed for the seismic
classification of drift-sensitive non-structural elements in
New Zealand
Non-Structural
Element Class
Median Drift Capacity
No damage
(SLS)
Life safety
(ULS)*
D1
0.25%
0.75%
D2
0.50%
1.5%
D3
0.75%
2.0%
D4
1.00%
2.5%
D5
1.50%
3.0%
* only applicable to those non-structural elements for which
failure would pose a life-safety threat.

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Table 2: Tentative PFA values and clearance
requirements for the seismic classification of acceleration-
sensitive non-structural elements in New Zealand
Non-
Structural
Element Class
Peak Floor
Acceleration
Capacity*
Installation Clearance
Requirements (mm)
No
damage
(SLS)
Life
safety
(ULS)**
Short
Period
(T<0.1s)
Medium/Long
Period+
(T=1.0s)
A1
0.25g
0.75g
5
50
A2
0.50g
1.00g
10
100
A3
0.75g
1.50g
15
150
A4
1.00g
2.00g
20
200
A5
1.50g
3.00g
30
300
* Refers to median peak floor acceleration for a standardized floor spectrum
** Only applicable to NSE for which failure would pose a life safety threat.
+ Fundamental period of NSE (interpolation/extrapolation permitted).
By way of an example, if a stiff-strong RC wall structure was
conceived as part of a conceptual design solution then, as a
result of the low drift demands and high accelerations that
would result, class D1 and class A3 non-structural elements
may be appropriate for that building. Alternatively, if a flexible
steel moment-resisting frame system was considered, then
floor accelerations would be limited but drifts would be high
so class D3 and class A1 non-structural elements may be
appropriate.
It is proposed that the classification of acceleration and drift
sensitive non-structural element systems will be developed via
various pathways including experimental, analytical and
historical performance evidence.
The classification system is expected to support the wider
appreciation of the compatibility of various non-structural
elements for the chosen primary structural option and enable a
more considered cost comparison between alternative design
scenarios (that include primary structure and non-structural
elements) to be undertaken early in the project, and from this
there is an opportunity to arrive at the best for project solution.
The classification system is also intended to support building
inspection of existing buildings to help understand the current
seismic risks and potential losses/business interruption, and
simplistic building inspection of new builds by knowing what
non-structural element classes the structural engineer has
defined and then using examples of each classification type to
inspect the installation.
Two-tier compliance pathway
A two-tier compliance pathway is proposed to align different
design and procurement routes to the scale and complexity of
the project.
The first compliance pathway is based on enhancing the
existing industry practice where the design and coordination of
non-structural elements is undertaken primarily by the
contractor during construction. Feedback was received from
contractors and sub-contractors that current ceiling void depths
provided in New Zealand are too tight to accommodate late
design and coordination of non-structural elements and hence
it is intended that this compliance pathway would potentially
include increased ceiling voids to say 1m deep in congested
areas to reduce the complexity of the coordination and
installation and increase the possibility of achieving a Code
Compliant outcome without significant rework. The non-
structural seismic classification system would be used by the
design team to choose the appropriate categories for drift and
acceleration sensitive components and these would be advised
in the construction contract documentation.
The second compliance pathway is when the design and
coordination of non-structural elements is undertaken as an
integrated process within the main building design. There
would be no minimum or maximum ceiling void depths as the
required spatial volume for the non-structural elements would
be assessed and confirmed to be sufficient throughout the
design process. To support a competitive tender process
spatial allocations can be provided within the design to enable
a range of services, partitions and ceiling systems to be
installed whilst minimizing the risk that the actual services,
partitions and ceiling systems chosen by the contractor would
require redesign or rework to achieve code compliance and the
performance requirements for the building.
For both pathways, at the completion of the project an
independent inspector (IQP) would be engaged to inspect and
certify the installation has been constructed in accordance with
the completed and coordinated design and achieves code
compliance prior to the Code Compliance Certificate being
issued.
Independent Inspection and Certification Body
The establishment of a new Independent Quality Provider
(IQP) and Certification Body (similar to the independent
inspection and certification requirements currently used for
Sprinkler Systems) would provide consistency of enforcement
in relation to the seismic performance of non-structural
elements to achieve Code Compliance and required building
performance. All projects (alterations to existing buildings
and new builds) would be inspected and signed off as being
code compliant by an IQP and submitted to the Building

8
Consent Authority with the Request for Code Compliance
Certificate documentation.
The IQP individuals would have considerable experience in
the design, coordination and installation of non-structural
elements.
Updates to Standards
The performance requirements for the seismic design of fire
sprinkler systems and suspended ceilings have recently been
updated and now align with the seismic design actions
standard (NZS 1170.5) and the New Zealand Standard for the
seismic performance of engineering systems (NZS 4219).
Industry users of the current Standards for non-structural
elements have advised there are gaps, inconsistencies and
errors in the current Standards with regard to seismic restraint.
It has also been demonstrated, within the research community,
that current code provisions provide poor prediction of the
acceleration demands (Sullivan et al., 2013) and drift limits
(Sullivan et al., 2020) for non-structural elements.
The proposed non-structural seismic classification system
discussed in the previous section will be developed based on
research and testing results to confirm the acceleration and
drift limits to the onset of damage, damage control limit state
and life safety for various arrangements of non-structural
elements and various detailing options.
The changes to design practice as a result of existing and future
research, testing and the proposed non-structural classification
system is expected to necessitate future updates to Standards.
It may be appropriate for the seismic design provisions for
non-structural elements to be brought into a one dedicated
Standard, Verification Method or Building Code Clause,
similar to ASCE-7/16 (2016), to ensure changes to seismic
design practice is applied consistently to all non-structural
elements. If the seismic design provisions and performance
requirements for non-structural elements are retained in the
individual component Standards there is potential for
inconsistency and contradiction in the future.
If a new Standard, Verification Method or Building Code
Clause was developed to cover the seismic design and
performance of non-structural elements it would enable
requirements that apply to all non-structural elements to be
located in a single source document. This could include a
consistent framework for mandatory independent inspection
and reporting for non-structural elements and systems by an
IQP. It is noted that this could be extended to involve annual
inspection, reporting and certification linked to the issue of the
annual Building Warrant of Fitness. A Building Warrant of
Fitness involves an annual inspection and report on all
specified systems that are crucial to the safety and health of a
building and those who use it (for example emergency lighting
systems).
Introduce a New Clause in the New Zealand Building
Code
In the future a new clause could be considered to be included
in the New Zealand Building Code to cover all aspects of Non-
Structural Elements and systems. A working title “B3 Non-
structural Elements and Systems” is proposed.
This new clause would cover performance requirements,
functional objectives and means of compliance for non-
structural elements and could also include provisions for
prefabricated building elements and products as well as the
seismic design, integration and performance of non-structural
elements in buildings.
The performance requirements section would expected to
focus on serviceability/damage control performance with
checks to ensure elements achieve life safety objectives. We
propose a philosophy that uses a significantly enhanced
‘serviceability’ demand over current New Zealand Standards.
We recommend this as there will be little to no additional cost
for many non-structural elements to achieve this and the
increase in performance of non-structural elements and
subsequent resilience of our building stock would be
significant.
Conclusions
Recent New Zealand earthquakes (Canterbury, Seddon and
Kaikōura), resulted in substantial economic losses and major
disruptions to our businesses and communities. Much of the
damage observed was to non-structural building elements. In
response to this, the industry is considering what changes can
be made to enhance the resilience of our built environment.
This paper has reviewed and described a number of possible
steps that could be made. If implemented, the changes
proposed in this paper would significantly improve the seismic
performance of buildings in New Zealand. Substantial co-
benefits are also expected to be realized including:
• Improved community resilience as the changes
penetrate further into our new and existing building
stock,
• Improved productivity of the construction sector as
the processes described in this paper are streamlined
and expanded to encompass the building as a whole,
resulting in projects routinely done once and done
right,

9
• Improved quality control, through clear definition of
roles and responsibilities and the introduction of an
Independent Qualified Persons (IQP) body,
• Building owners, tenants and insurers will better
understand the risk of building damage and downtime
as a result of more frequent seismic events and take
ownership for decision making and be prepared to
invest in resilience.
References
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Arifin, F., De Francesco, G., Sullivan, T.J., Dhakal, R.P.,
2020. Developing guidelines for the seismic assessment of
glazing systems. Annual Conference of NZ Society for
Earthquake Engineering (NZSEE20), Wellington, 10pp.
ASCE 7-16, 2016, Minimum Design Loads and Associated
Criteria for Buildings and Other Structures, American Society
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