link to page 1 link to page 1 link to page 1

133 Molesworth Street
PO Box 5013
Wellington 6140
New Zealand
T+64 4 496 2000
20 June 2022
Jack Hulls
By email: [FYI request #19468 email]
Ref: H202206948
Tēnā koe Jack
Response to your request for official information
Thank you for your request under the Official Information Act 1982 (the Act) to the Ministry of
Health (the Ministry) on 25 May 2022. You requested:
“information about the earthquake assessment of the ministry of health head office
building on molesworth st.
Of interest is when was it last assessed and what was the result”.
The Ministry has identified two documents within scope of your request, itemised in Appendix 1
of this letter. The table in Appendix 1 outlines the grounds under which I have decided to
withhold information. Where information is withheld under section 9 of the Act, I have
considered the countervailing public interest in release in making this decision and consider that
it does not outweigh the need to withhold at this time.
The Ministry head office located at 133 Molesworth Street is a leased building that was
redeveloped back in 2015. At the time construction was finished, the building was declared to
have achieved one hundred percent of the New Building Standard (NBS) at Importance Level 31
(IL3), although the building would only generally meet the definition of IL2. As such, when
discussing the strength of the building it is usually stated as being 130% IL2.
Furthermore, as the building does not contain the structural elements of concern as detailed in
section C5 of the Engineering Assessment Guidelines (Yellow Chapter)23, the structural
assessments provided can be considered current.
I trust this information fulfils your request.
Under section 28(3) of the Act, you have the right to ask the Ombudsman to review any
decisions made under this request. The Ombudsman may be contacted by email at:
[email address] or by calling 0800 802 602.
1 https://www.legislation.govt.nz/regulation/public/1992/0150/latest/DLM162576.html#DLM4417717
2 http://www.eq-assess.org.nz/wp-content/uploads/2018/11/c5-concrete-buildings.pdf
3 https://www.building.govt.nz/building-code-compliance/b-stability/b1-structure/what-you-need-to-know-
section-c5-concrete-buildings-proposed-revision/

Please note that this response, with your personal details removed, may be published on the
Ministry website at: www.health.govt.nz/about-ministry/information-releases/responses-official-
information-act-requests.

Nāku noa, nā

Celia Wellington
Deputy Director-General
Corporate Services

Page 2 of 3

Appendix 1: List of documents for release

#
Date
Document details
Decision on release
1
26 May 2015  Letter from Beca to Molesworth  Some information withheld under
Of ice Trustee Ltd – 133
section 9(2)(a) of the Act, to protect
Molesworth St Redevelopment –  the privacy of natural persons.
Update to Importance Level 3
2
10 October
Letter from Beca to Molesworth  Some information withheld under
2016
Of ice Trustee Ltd – 133
section 9(2)(a) of the Act.
Molesworth St – Structural
Statement for CPU

Page 3 of 3

Document 1
85 Molesworth Street
PO Box 3942, Wellington 6140, New Zealand
T: +64 4 473 7551 // F: +64 4 473 7911
E: [email address] // www.beca.com
Molesworth Office Trustee Limited
26 May 2015
PO Box 30626
Lower Hutt 5040
New Zealand
Attention: Mike McCombie
ACT 1982
Dear Mike
133 Molesworth St Redevelopment - Upgrade to Importance Level 3
Further to our discussions in relation to the Importance Level of 133 Molesworth St, we are pleased to
summarise the key changes and benefits of upgrading from Importance Level 2 (IL2) to Importance Level 3
(IL3).
The New Zealand loadings standard AS/NZS1170.0:2002 defines Importance Level for a building and sets
out loadings for gravity, wind, earthquake and other loading conditions. The required building Importance
INFORMATION
Level is based mainly on the building use, occupancy level and design life. Most office buildings are only
required to be IL2 – it is rare for an office building in New Zealand to be IL3 and would general y only apply to
buildings that are very large and/or have a large occupancy.
Beca has carried out investigations into the requirements for an upgrade to IL3, which included:
n  Analytical model ing of the building
n  Preliminary design of new lead rubber bearings to arrive at a feasible replacement bearing design
n  Consideration of implications on the foundations and superstructure.
An upgrade to IL3 wil  be achieved for 133 Molesworth St with revisions to the design, which includes the
following considerations:
n  Because of increased seismic demands, the base isolation system will require an upgrade which will
involve the replacement of 39 of the existing lead-rubber bearings with new, higher performing lead-rubber
bearings.  Mainly around the perimeter of the building.
n  Because of increased wind loading, the building cladding and roofing systems require some upgrade.
n  The increased demands on the suspended ceilings and services have also been considered.
Benefits
The main benefits of changing from IL2 to IL3 are:
n  The seismic capacity of the building is increased by 30%.  That is, IL2 buildings are designed to remain
standing after a 1-in-500 year seismic event, which has a 10% chance of being exceeded in a 50-year
RELEASED UNDER THE OFFICIAL
period. IL3 buildings are designed to remain standing after a 1 in 1000 year seismic event, which has a
5% chance of being exceeded in a 50-year period.
n  The wind capacity of the building is increased by approximately 10%, in terms of ability to resist design-
level wind.  That is, IL2 buildings are designed to remain standing after a 1-in-500 year wind event, which
Our Ref: 5292891
NZ1-10722892-5  0.5

Document 1
Page 2
26 May 2015

has a 10% chance of being exceeded in a 50-year period. IL3 buildings are designed to remain standing
after a 1-in-1000 year wind event, which has a 5% chance of being exceeded in a 50-year period.
In summary, an IL3 building will provide a safer, more robust building than an equivalent IL2 building Due to
increased robustness, the chance of disruption to business operations as a result of damage to the primary
structure following an earthquake is also reduced.
ACT 1982
Additional Benefit of Base Isolation
Base isolation inherently provides a high level of protection to the building contents which include non-
structural elements such as ceilings, partitions and building services. The efore base-isolated buildings are
more likely to remain operational after an earthquake than an equivalent non base-isolated building.
We trust this letter meets your requirements. Should you have any questions please do not hesitate the
undersigned.

INFORMATION
Yours sincerely
S9(2)(a)
Technical Director - Structural Engineering

on behalf of
Beca Ltd
Direct Dial:

S9(2)(a)
Email

S9(2)(a)
R THE OFFICIAL

RELEASED UND
Our Ref: 5292891
NZ1-10722892-5 0 5

Document 2
85 Molesworth Street
PO Box 3942, Wellington 6140, New Zealand
T: +64 4 473 7551 // F: +64 4 473 7911
E: [email address] // www.beca.com
John Robinson
14 October 2016
Molesworth Office Trustee Ltd
PO Box 30626
Lower Hutt, 5040
ACT 1982
Dear John
133 Molesworth St - Structural Statement for CPU
The structural redevelopment work was designed to achieve 100% New Building Standard (%NBS)
in accordance with NZSEE guidelines 2006 (including Corrigenda 1 and 2) and NZS1170.5:2004
assuming an Importance Level of 3.
Based on our site inspections carried out to CM3 in accordance with ACENZ/IPENZ guidelines, and
information supplied by the contractor to date, we believe on reasonable grounds that the
redevelopment works have been carried out generally in accordance with our design documents as
INFORMATION
consented under building consent Nº SR318039 and amendments 1,2&3 and subsequently altered
by Consultant Advice Notices 1-243.
On this basis we see no reason why the building should not be occupied after 28th October 2016.
We trust this letter is satisfactory. If you have any questions please do not hesitate to contact the
undersigned.
Yours sincerely
S9(2)(a)
E OFFICIAL
Senior Associate - Structural Engineering
on behalf of
U
Direct Dial:

S9(2)(a)
Email:

S9(2)(a)
© Beca 2016 (unless Beca has expressly agreed otherwise with the Client in writing).
This report has been prepared by Beca on the specific instructions of our Client. It is solely for our Client’s use for the
purpose for which it is intended in accordance with the agreed scope of work. Any use or reliance by any person contrary to
RELEAS
the above, to which Beca has not given its prior written consent, is at that person's own risk.
Our Ref: 5292891
NZ1-13208495-2  0.2

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