Historic Heritage Delivery Work Plan Part A Built Heritage

Auckland City Rail Link In association with:

CONSTRUCTION WORKS CONTRACT 1 HISTORIC HERITAGE DELIVERY WORK PLAN Part A – Built Heritage Section Document ref: CRL-BTM-ENV-DOW-PLM-000280

Revision: 11 July 2018

COMMERCIAL IN CONFIDENCE Historic Heritage Delivery Work Plan

July 2018

Version history Rev.

Date

Version details

Prepared by

Reviewed by

1

November 2015

Draft for Auckland Transport Review

B Petry, A Parkinson

R Purdy, P Roan

2

November 2015

Drat for CLG review

B Petry, A Parkinson

R Jenkins

3

January 2016

Draft for peer review

B Petry, A Parkinson

R Purdy

4

April 2016

Draft incorporating revised BTC designation conditions, Independent Peer Review and Auckland Council comments

B Petry

R Purdy, P Roan, R Jenkins

5

April 2016

Draft for consultation/CLG review

B Petry

R Purdy

6

May 2016

Draft incorporating CLG comments and for HNZPT and Auckland Council review

B Petry

R Purdy, R Jenkins

7

May 2016

Draft incorporating CLG review for Independent Peer Review

B Petry

R Purdy, P Roan

8

May 2016

Draft incorporating CLG and Cooper and Company comments for Auckland Transport review

B Petry

J Urquhart, P Roan

9

June 2016

Final

B Petry

J Urquhart, P Roan, R Jenkins

10

October 2017

Annual plan review

A Matthews

S Sutherland

11

July 2018

Annual plan review

A Matthews

S Sutherland

Distribution Date

Version

Issued to

Quantity & type

Approved for the DSBJV by

11 November 2015

Draft

Auckland Transport

1x Electronic

D Burtenshaw

13 November 2015

Draft

Community Liaison Group

1x Electronic

D Burtenshaw

28 January 2016

Draft

Independent Peer Review

1x Electronic

D Burtenshaw

11 April 2016

Draft

Auckland Transport

1x Electronic

D Burtenshaw

12 April 2016

Draft

Community Liaison Group

1x Electronic

D Burtenshaw

4 May 2016

Draft

HNZPT and Auckland Council

1x Electronic

D Burtenshaw

9 May 2016

Draft

Independent Peer Review

1x Electronic

D Burtenshaw

27 May 2016

Draft

Auckland Transport

1x Electronic

D Burtenshaw

2 June 2016

Final

Auckland Transport

1x Electronic 1 x Hard Copy

D Burtenshaw

28 November 2017

Draft

CRLL

1 x Electronic

D Burtenshaw

21 December 2017

Draft

Auckland Council

1 x Electronic

D Burtenshaw

2 July 2018

Final

CRLL, Auckland Council

1 x Electronic

D Burtenshaw

19 December 2018

Draft

CRLL, Auckland Council

1 x Electronic

D Burtenshaw

This document remains the property of DSBJV. Its contents are confidential and shall not be reproduced, destroyed or given away without express, written permission of DSBJV. The electronic version of this document in FULCRUM on

Historic Heritage Delivery Work Plan – Built Heritage

July 2018

designated serves(s) is the Master Copy and is a controlled document. Unless specifically noted, thereon, other copies of this document are uncontrolled. j:\crl c1\08 environment sustainability\0801 environmental management plans and delivery work plans\x annual management plan reviews\2018\tracked change - draft versions\crl-btm-env-dow-pln-000280 hh dwp built heritage rev 11.docx

Historic Heritage Delivery Work Plan – Built Heritage

July 2018

Table of contents 1

2

3

4

5 6

7

8 9

Introduction 1.1 Purpose of Historic Heritage Delivery Work Plan – Built Heritage 1.2 Relevant Designation Conditions 1.3 Sustainability Historic Heritage Values – Built Environment 2.1 Overview of Built Heritage in the Project Area 2.2 Former Chief Post Office Specific Significant Features of CPO CPO Heritage Protection Consideration of Construction Method 3.1 Overview of Construction Method 3.2 Assessment of Alternative Construction Methods CPO Building Works Building Record and Salvage Strategy 4.1 Overview 4.2 Building Record Methodology Recording Techniques and Standards Measured Drawings Written Records Photographic Recording/Photography 4.3 Salvage Strategy Methodology Elements to be removed and stored Refitting of elements following construction 4.4 Building Record and Salvage Strategy Report Monitoring Methodology 5.1 Monitoring Prior to and During Construction Pre and Post-Construction Surveys of Built Heritage 6.1 Pre-Construction Surveys 6.2 Photographic (or Video) Documentation Photographic Technical Requirements Protection Methodology 7.1 Overview of Protection Methodology for CPO 7.2 Protection Methodology for Specific CPO Exterior and Interior Features CPO Exterior Features CPO Interior Features 7.3 General Protection of Historic Interior Features and Finishes 7.4 Fire Protection 7.5 Security 7.6 Managing damage from vibration, ground movement or water ingress Vibration Ground Movement Water Ingress 7.7 Monitoring and Supervision of Sensitive Works Rectification Methodology General Matters 9.1 Project Built Heritage Specialist roles and responsibilities 9.2 Contractor briefing

Historic Heritage Delivery Work Plan – Built Heritage

1 1 2 4 5 5 6 7 7 9 9 9 9 12 12 12 12 12 13 14 15 15 15 16 17 17 18 18 18 18 20 20 20 20 21 23 24 24 25 25 25 25 25 27 28 28 28

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10 11

12

13

9.3 Training 9.4 Recording and Supervision 9.5 Contact details Communication and Consultation Heritage Covenant – Reinstatement of Heritage Elements 11.1 Proposed Reinstatement Works Entrance Vestibule and Stairway (Heritage Core) CPO Ground Floor – General Banking Chamber Ceiling Banking Chamber Public Space Column Bases Retail and customer service areas Ticket Gateline Openings into Tyler and Galway Street Signage Heritage Interpretation Strategy Plan Review and Updating of the DWP 12.1 DWP Review 12.2 DWP Updates Management and Control of Documents

Appendix A :

ISCA Requirements

Appendix B :

CPO Conservation Plan

Appendix C :

Specific heritage features of the CPO

Appendix D :

CPO Heritage Covenant

Appendix E :

CPO Diaphragm Wall Plan

Appendix F :

Building Record and Salvage Strategy

Appendix G :

Consent in principle to works within the provisions of the deed of heritage covenant dated 18 July 1995

Appendix H :

CLG and Independent Peer Review Comments

Appendix I :

Register of Plan Updates

Historic Heritage Delivery Work Plan – Built Heritage

28 28 28 29 30 30 30 30 30 31 31 31 31 31 31 31 32 33 33 33 35

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Glossary of abbreviations Acronym

Definition

ACDP BTC CEMP CHI CPO CRL CRLL DSBJV DWP HNZPT HNZPTA IS ISCA PAUP

Auckland Council District Plan (Central Area Section) Britomart Transport Centre Construction Environmental Management Plan Cultural Heritage Inventory Former Chief Post Office building City Rail Link City Rail Link Limited Downer Soletanche Bachy Joint Venture Delivery Work Plan Heritage New Zealand Pouhere Taonga Heritage New Zealand Pouhere Taonga Act 2014 Infrastructure Sustainability Infrastructure Sustainability Council of Australia Proposed Auckland Unitary Plan

Glossary of terms Term

Definition

The List

New Zealand Heritage List/Rārangi Kōrero (formerly the Register) for information about New Zealand's significant heritage places.

Historic Heritage Delivery Work Plan – Built Heritage

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1

1

Introduction

The City Rail Link (CRL) project comprises the construction, operation and maintenance of a 3.4 km underground passenger railway, running between Britomart Station and the North Auckland Rail Line in the vicinity of Mt Eden station. The works relating to this Built Heritage Section of the Historic Heritage Delivery Work Plan (DWP) constitute part of the enabling works for the CRL. The works (the Project) involve the construction of an extension to the existing passenger rail network from the current termination point within the Britomart Transport Centre (BTC), westwards underneath the former Chief Post Office building (CPO) and lower Queen Street (as shown by the blue shaded area in Figure 1.1 below).

LEGEND CRL alignment BTC designation CRL designation C1 worksite

Figure 1.1: Project Footprint

1.1

Purpose of Historic Heritage Delivery Work Plan – Built Heritage

The Built Heritage section of the Historic Heritage DWP (Part A) has been prepared in accordance with Condition 41 of the CRL designation and Condition 29 of the BTC designation 1. The purpose of the Built Heritage Section of the Historic Heritage DWP is to manage the adverse effects on built heritage, including the CPO that may result from associated works prior to, during, and after the construction of the Project.

The objective of this DWP is to avoid where practicable, or otherwise minimise adverse effects on the heritage values of the CPO and, where relevant, other buildings during the construction of the Project works, adopting the best practicable option.

Part A of the Historic Heritage DWP (2016) was prepared by Reverb for the Downer Soletanche Bachy Joint Venture (the Contractor - DSBJV) and forms part of the Construction Environmental Management Plan (CEMP) for the Project. An updated version of this DWP has been prepared by Matthew and Matthew Architects.

Condition 41 of the CRL designation requires the preparation of a Historic Character DWP ‘Built Heritage Section’, while Condition 29 of the BTC designation requires the preparation of a ‘Chief Post Office Built Heritage DWP’. For clarity, the reference “Built Heritage Section of the Historic Heritage DWP” has been used throughout this document, which addresses and satisfies both the CRL and BTC designation conditions.

1

Historic Heritage Delivery Work Plan – Built Heritage

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2

1.2

Relevant Designation Conditions

Table 1.1 identifies the designation conditions relevant to the Built Heritage Section of the Historic Heritage DWP and where they are addressed in the document.

Table 1.1: Condition No. 41.1

41.2

41.2 (b)

41.2 (e)

41.2 (f) 41.2 (g)

29.1

Historic Heritage - Built Heritage Conditions and DWP section where addressed Condition

Relevant section of DWP

City Rail Link Designation The Historic Character DWP shall be prepared to manage This document the adverse effects on built heritage and archaeology that may result from associated works prior to, during, and after the construction of the City Rail Link or any part of it.

The objective of the Built Heritage section is to avoid, This document remedy or mitigate adverse effects on built heritage as far as reasonably practicable. To achieve the above objective, the following shall, as a minimum, be included in the built heritage section of the Historic Character DWP: The proposed methods for monitoring building damage Section 5 that is to be undertaken by a suitably qualified person for the duration of construction works. This includes confirming which Built Heritage buildings and structures are to be subject to a pre and post building condition survey through: (i) Using the updated predicted vibration contours undertaken in Condition 36; (ii) Reviewing those buildings in Appendix 2 to these conditions in accordance with Condition 46.1; (iii) Reviewing buildings within the designation footprint (including above sub-strata designation) or located in close proximity to identify buildings which have been recognised as having heritage value as a result of scheduling under the Historic Places Act 1993 or in the Auckland Unitary Plan.

How Built Heritage Buildings and Structures will be Section 7 protected during construction through the use of screening or other protective measures to mitigate adverse construction effects; How mitigation or rectification of damage to Built Heritage Section 7 & 8 Buildings and Structures will be addressed; and Cross references to the specific sections in the Section 10 Communication and Consultation Plan which detail how the Auckland Council Heritage Department, the New Zealand Historic Places Trust, and mana whenua (see condition 15) are consulted, and the communication with the general public on the management of the adverse effects relating to Build Heritage.

Britomart Transport Centre Designation 2 This document A Chief Post Office Built Heritage DWP (CPO DWP) shall be prepared to provide a framework to manage the adverse effects on the built heritage values of the CPO and, where

Conditions as attached to Auckland Transport’s Confirmation Notice of 17 March 2016 on Notice of Requirement to alter Britomart Transport Centre Designation

2

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3 Condition No.

Condition

Relevant section of DWP

relevant, other buildings referenced in this condition, during, and after the construction of the Project.

Those aspects of the CPO DWP relating to the CPO building shall be based on the Chief Post Office Revised Conservation Plan (2003).The Requiring Authority shall consult HNZPT, and Auckland Council’s Built Heritage Unit and the CPO long-term lessee in the preparation of the CPO DWP. 29.2

The objective of the CPO DWP is to avoid where practicable or otherwise minimise adverse effects on the heritage values of the Chief Post Office and, where relevant, other buildings, during the construction of the Project works (including reinstatement) adopting the best practicable option. To achieve the above objective, the following shall, as a minimum, be included in CPO DWP:

29.2 (a) 29.2 (b)

Identification of the key heritage values of the building.

29.2 (c)

Details of how the option selected by the Requiring Authority achieves the objective of the CPO DWP.

Section 3

29.2 (d)

Preparation of a Building Record and Salvage Strategy that outlines a suitable set of procedures for the removal, storage and for later refitting and reuse of elements of the CPO. The proposed methods for monitoring building damage that are to be undertaken by a suitably qualified person for the duration of the Project works.

Identification and methodology for recording Built Heritage elements directly affected by the construction, or associated pre- and post-construction, which are to be: (i) Adaptively reused; (ii) Partially retained in design and construction; (iii) Integrated into other elements of the City Rail Link.

Section 4

29.2 (g)

The key stages of the preferred construction option when a suitably qualified heritage architect will be required on site to monitor sensitive works and to make decisions regarding construction works that may result in adverse effects on the built heritage values of the Chief Post Office building.

Section 7.7 & 9.4

29.2 (h)

In addition to the CPO, the CPO DWG is to detail: i) How other Built Heritage Buildings and Structures will be protected during construction through the use of screening or other protective measures to mitigate adverse construction effects; and ii) How mitigation or rectification of damage to Built Heritage Buildings and Structures identified in Appendix 1 will be addressed.

Section 7 & 8

29.2 (e)

29.2 (f)

Details of the assessment of alternative construction methods which may achieve the objective of the CPO DWP.

Historic Heritage Delivery Work Plan – Built Heritage

Section 2 Section 3

Section 5

Section 6 & 7

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4 Condition No.

Condition

Relevant section of DWP

29.2 (i)

Cross references to the specific sections in the Communication and Consultation Plan which detail how HNZPT, Auckland Council’s Built Heritage Unit and the CPO long-term lessee (see condition 16) are consulted, and the communication with the general public on the management of the adverse effects relating to Built Heritage.

Section 10

29.2 (j)

How reinstatement works for the CPO building will address the permanent treatment of heritage elements identified in the Heritage Covenant and Revised Conservation Plan (2003).

Section 11

1.3

Sustainability

City Rail Link Limited (CRLL) is seeking an Infrastructure Sustainability Council of Australia (ISCA) Infrastructure Sustainability (IS) rating for the Project. Further details can be found in the Project CEMP and Sustainability Rating Management Plan. Project sustainability requirements that relate directly to the Built Heritage Section of the Historic Heritage DWP are included in Appendix A. These requirements are imbedded within the Delivery Work Plans and management plans for the Project to ensure that sustainability is a key focus and ‘the way we do things’. In some cases the IS requirements and sustainability goals enhance the designation requirements.

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2

Historic Heritage Values – Built Environment

2.1

Overview of Built Heritage in the Project Area

Table 2.1 outlines the built heritage features located in the Project area. The location of these features is shown in Figure 2.1.

Table 2.1:

Identified Built Heritage

Address

Property

10 Customs Street East

Barrington Building

14-18 Customs Street East

Old Sofrana House

20 Customs Street East

CHI

HNZPT

ACDP 3

Heritage Listing

ACDP

HNZPT

Type (Refer App B)

7291

1937

B

2

X

12551

4576

019

B

2

X

Levy Building

3077

7292

2

X

2 Queen Street

Endeans Building

2550

4597

2

X

12 Queen Street

Former CPO

2511

101

1

X

117

A

Barrington Building 10 Customs Street East

Old Sofrana House 14-18 Customs Street East Levy Building 20 Customs Street East

Former CPO - Britomart Transport Centre, 12 Queen Street

Endeans Building – 2 Queen Street

Figure 2.1: Location of Built Heritage in relation to Project footprint

3

Auckland Council District Plan (Central Area Section)

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6

2.2

Former Chief Post Office

The former Chief Post Office building (CPO) is a very significant historic place and is amongst one of the most highly recognised in New Zealand. The building is a well-preserved example of urban commercial architecture in the Edwardian Baroque style of architecture. It was erected between 1909 and 1912 to a design by the Government Architect’s Department to serve as a replacement main post office for Auckland. The building is part of the Britomart Precinct that was redeveloped between 1995 and 2003 as the Britomart Transport Centre.

The CPO is a building of exceptional significance in Auckland for the following reasons: •

It was Auckland's Chief Post Office - a building that survives from a time when the State was committed to providing public services.

•

The design of the CPO exemplified contemporary building practice and engineering techniques, with the use of steel frame, and pile foundations in combination with masonry construction.

•

It’s setting in the modern Auckland landscape and, in particular, its contribution to the urban character of one of the best-preserved 19th century districts in the Central Business District (Britomart Precinct).

•

The CPO is the foremost example of Edwardian Baroque designed Public Building in Auckland and is a reflection of New Zealand's post-colonial links to Europe.

Elements of the CPO building, which have been identified as having heritage value, are noted in Table 2.2 4.

Table 2.2:

Identified Built Heritage values

Architectural Style and Elements: Exterior

Architectural Style and Elements: Interior

• The CPO is an example of the Imperial Baroque style, a national architectural style which expressed British commercial and imperial aspirations, and which flourished in New Zealand under John Campbell in a Post Office building programme that lasted almost a decade, producing ornate and complex Post Offices.

• The large Oamaru stone structure on a Coromandel granite plinth with brick masonry finished in cement render to the lesser elevations.

• The domed tower on the north and south of the building are of particular note.

• The Modern 2000s addition contrasts with the baroque style of the CPO. It is linked by a small glass transitional area, so minimal damage was done to the heritage fabric.

• Main Entrance Lobby/Vestibule – including mosaic tiled paving and floor, Pilkington and other ceramic wall tiles, cartouches, architraves, dadoes, granite arches, plasterboard walls and ceilings.

This area is one of the most significant spaces within the CPO, using colourful decorative techniques, high quality permanent materials, and employing the best trade practices. The use of three-dimensional tile ornamentation is very significant here.

• Main Banking and Postal Chamber - including plastered columns decorative capitals, six glazed domes with coloured coffered ceiling and timber floor (currently under vinyl).

The main postal and banking chamber was a gracious space, defined by columns and glazed timber screens. The room was furnished with fittings of high quality materials to create a room

Heritage values have been identified by way of discussions with HNZPT and the Auckland Council Built Heritage Unit, review of the CPO Conservation Plan (1995) and the Revised Conservation Plan (2003), site visits and data collection via non-destructive material analysis, verbal heritage assessment provided to the Project design team on the current form of the CPO building in relation to the Revised Conservation Plan (2003) and previous reporting i.e. Britomart Transport Centre (CPO) Queen Elizabeth II Square, Auckland Built Heritage Impact Assessment for the Britomart Transport Centre Notice of Requirement dated 25 May 2015, prepared by Reverb

4

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7 Architectural Style and Elements: Exterior

Architectural Style and Elements: Interior of appropriate dignity in which to carry out banking and associated business. Features included an enormous curved counter, mosaic floors, Brocatella marble panels, wrought brass screens, varnished panelled timber screens, large panes of translucent glass, and elegant lamps.

Little remains of these original fittings, and it is now the columns and the ceiling that recall the previous grandeur of the space. The five small, and one large glazed domes, and supporting Doric columns along with the windows, are the only original elements remaining in place in this area.

• Stair Landing - the stair landings are a vertical continuation of the public space of the vestibule, with arches, keystones, tiled dado, wrought iron balustrade, collapsible gate and a newel post and other exterior features.

The arches on each landing originally opened from the corridor on to the landing and the stairwell, and the 2001 alterations have significantly altered the architectural quality of the landings, stairwell and corridor.

The Conservation Plan for the CPO presents additional information on heritage values (refer to Appendix B). The Conservation Plan forms an appendix to the Heritage Covenant associated with the CPO.

Specific Significant Features of CPO A detailed description of the various features and values of the CPO are presented in Appendix C. This includes an assessment and scoring of individual elements of the building and its values.

CPO Heritage Protection Table 2.3 outlines the specific heritage protection afforded to the CPO under relevant legislation, policy and planning documents.

Table 2.3:

Overview of CPO Heritage Protection

Description

Listing

Auckland Council District Plan (Central Area Section) Proposed Auckland Unitary Plan

The CPO is identified as Historic Heritage Place 117.

Heritage New Zealand

The CPO is located in the ‘Britomart sub-precinct B’ Sub-precinct and identified as Historic Heritage Place ID 2021 (Category A item). The key Heritage Values associated with the item are: A : Historical, B : Social, F : Physical attributes, G : Aesthetic and H : Context The following are listed on the Heritage New Zealand List: • The Chief Post Office, its fittings and fixtures are identified as a Category I place (ID 101). This listing includes recent modifications (21 August 2001).

• The Britomart precinct

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8 Description

Listing • Customs Street Historic Area (ID 7160) • Quay Street Historic Area (7159) • Harbour Historic Area (ID 7158)

Cultural Heritage Index (Auckland Council) Heritage Covenant Chief Post Office Conservation Plan

ID 2511

The CPO is subject to a Heritage Covenant registered on the Certificate of Title.

A copy of the Covenant is attached as Appendix D. The CPO is subject to a Conservation Plan entitled ‘Chief Post Office QEII Square Auckland A revised Conservation Plan’ dated April 2003 and prepared by Salmond Reed Architects 5

The Chief Post Office Conservation Plan (2003) is currently being revised by Reverb in order to reflect the current condition of the CPO building. References to the CPO Conservation Plan (2003) in this DWP will be updated to reflect the Revised Conservation Plan (2015) once the Conservation Plan is finalised.

5

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9

3

Consideration of Construction Method

3.1

Overview of Construction Method

A description of the construction method for the Project is provided in the CEMP. In summary, the method will involve the following works within or beneath the CPO: •

The dismantling and removal of fittings and fixtures and retail outlets/customer service kiosks within the Britomart Station ticket hall that were constructed during the Britomart Transport Centre redevelopment works in 2002-2003.

•

Demolition and removal of the floors of the main ticket hall (former Banking Chamber) on the ground floor of the CPO in order to provide construction access to beneath the building. The existing raised timber floor in the main ticket hall will be removed and stored during the construction works.

•

Construction of a diaphragm wall, underpinning and piling work to support the foundations of the CPO and enable construction of the rail tunnels under the CPO.

•

Excavation below the CPO building, rail tunnel construction and concreting activities.

•

Backfilling of construction area around the rail tunnels below the CPO.

•

Reinstatement of areas/features of the CPO subject to the Project construction works.

Reinstatement will be undertaken in accordance with the agreement between CRLL and Heritage New Zealand Pouhere Taonga (HNZPT) under the Heritage Covenant associated with the former CPO building.

•

On completion of the works, the ground floor level of the CPO is proposed to be reinstated to a passenger entry/ exit and concourse level incorporating the rail ticketing gatelines.

Since the original DWP was written, two areas of additional works have been identified which have the potential to effect the heritage features of the CPO Building. This includes: •

•

Underpinning – the method proposed requires collars to be fixed to the columns inside the CPO Building. There are consequential works to allow for installation of collars, including the removal of the concrete encasement around the columns to expose the steel columns.

Basement area under the entrance lobby - the works under the lobby space to underpin the upper floors requires removal of the remnant basement lobby space not already removed as part of the works in 2002. This is to allow for the construction of two 1500 x 800 beams against the north and south walls.

Further details about the recording and reinstatement in these areas is provided in Section 4.

3.2

Assessment of Alternative Construction Methods

This section provides an assessment of construction methods for the CPO works in accordance with BTC designation Conditions 29.2(b) and (c). Specifically, this section provides an assessment of the use of bored pile walls under the CPO as per the CRL reference design and the preferred design of a diaphragm wall solution.

All other key aspects of the Project design and construction methodology for the CPO remain as per AT’s original CRL reference design.

CPO Building Works The location of the proposed CRL tunnels beneath the CPO conflicts with the building’s current piled foundations. Additional foundation underpinning is required to enable construction of the tunnels under the CPO building.

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10 The works required to provide additional support to the CPO and surrounding ground in order to enable construction of the CRL tunnels are heavily restricted by headroom limitations, along with limitations associated with the high heritage values of the ground floor support structures.

3.2.1.1

Reference Design

AT’s original CRL reference design for the Britomart Station works involved the use of bored pile walls and bentonite cement columns to provide the necessary temporary support and water retention to the CPO and surrounding ground during the construction works. The design included installation of a pile wall extending beneath the CPO along the lower Queen Street building frontage, along with the installation of several pile walls inside, underneath and immediately adjacent the CPO. The pile walls comprised the installation of 226 bored piles, requiring the excavation of 2,778 m3 of material from beneath the CPO. Installation of the piles involved holes and slots being cut in the basement floor and internal walls to construct the wall. The design of the wall was such that there would be no physical connection between the piles, requiring the use of jet grout blocks extending over gaps in the pile wall.

3.2.1.2

CPO Building Works – Preferred Option

The preferred (DSBJV) design for the Britomart Station works, which has been approved by CRLL, involves the installation of a diaphragm wall solution beneath the CPO, instead of the bored pile walls. A diaphragm wall is a reinforced concrete wall that is made in situ.

In order to construct the diaphragm walls, a trench will be excavated and construction will commence with installation of a precise guide wall. The trench for the wall will be prevented from collapsing during excavation, via reinforcing and casting with the use of bentonite slurry. The slurry forms a thick deposit on the walls of the trench, which balances the inward hydraulic forces and prevents water flow into the trench. The joint between adjacent panels is achieved by using a temporary steel stop end, allowing the placement of a water stop across the joint, and providing a guide for the excavating tool at the same time.

The outer walls will be 800mm thick and the inner walls will be 630mm thick. The walls will be installed to a depth of approximately 18m and embedded into the rock below the CPO building.

Refer Appendix E, which show the location of the diaphragm walls.

The diaphragm wall will be excavated in sections, approximately 2-3 m in length, using a Hydrofraise HC05® rig. This machine is the most compact rig of its type in the world, consisting of a hydromill cutting head and rope suspended on a purpose built crawler unit. Approximately 2,500 m³ of material will be excavated as part of the diaphragm wall installation.

Due to space constraints beneath the south eastern corner of the CPO building, the diaphragm wall rig is unable to access this area and install a diaphragm wall. As such, three composite bored piles will be installed in this location as per the reference design.

A number of smaller piles will be installed under the Basement 1 level and under the CPO lobby area in order to provide additional support to the loadings on the CPO building as a result of the new construction works.

Refer to Sections 2.2.2.2 and 2.2.2.3 of the Project CEMP for further detail in regard to the construction methodology for works below the CPO. 3.2.1.3

Benefits on Heritage Values

The use of diaphragm walls to provide support to the CPO and surrounding ground, as opposed to the use of bored pile walls as per the reference design, will result in a number of constructability

Historic Heritage Delivery Work Plan – Built Heritage

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11 benefits and reduced potential impacts on the heritage values of the building, and as such will achieve the objectives of this DWP (refer to Section 1). This is due to the following: a

b

c

d

e

f

The diaphragm wall solution will be much faster to construct than the bored pile walls, taking approximately 5 months to construct, as opposed to 8 months for the pile wall. This will reduce the time that the building interior will be open to construction.

The diaphragm wall will result in a large reduction in the extent and volume of excavation required below the building to install the wall, in comparison to the pile walls, and will reduce the potential for settlement.

The diaphragm wall will significantly reduce the volume of cement and steel required to support the building - 690 tons of cement and 260 tons of reinforcement bars are required for the diaphragm wall, as opposed to 860 tons of cement and 870 tons of steel columns for the pile walls.

The diaphragm wall design is such that the walls will provide a watertight solution, which will result in reduced settlement impacts, and thus reduced effects on the building. It is an enhancement to the pile walls proposed by the reference design.

The stiffer nature of the diaphragm walls allows for a substantial reduction in props below the building, including the omission of one level of struts, and as such reduces the amount of works within the building.

Overall, the diaphragm walls will serve to maintain greater integrity of the CPO than the reference design pile wall proposal, and reduces the potential impact on heritage values of undertaking such construction works within the ground floor of the building.

The installation of the smaller permanent piles below the CPO Basement 1 level and lobby will also provide additional support to the building, which is preferable from a heritage perspective in order to minimise the potential for impacts on the heritage values of the building.

For the reasons outlined above, the DSBJV design will achieve the objectives of this DWP to a greater extent than the reference design. Furthermore, from a heritage perspective, the DSBJV solution will only affect the fabric, features and areas of the CPO impacted through the redevelopment and conversion of the building into the current Britomart Transport Centre in 2002-2003, which also achieves the objectives of this DWP.

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4

Building Record and Salvage Strategy

4.1

Overview

The construction works will be predominantly undertaken within the ground floor of the CPO, hence, recording should be most comprehensive in this area. However, as other areas of the CPO have the potential to be effected, the exterior and upper floors should also be documented to ensure a comprehensive record before, during and after construction. The reasons for this are two-fold, firstly to record the building and historic elements before work commences and then to clearly record any potential effects resulting from construction (both positive and negative). Refer to Section 6 of this DWP for further detail regarding pre and post-construction surveys of built heritage.

Given the nature of the works, little salvage works are expected, however a conservative approach should be adopted. Prior to the commencement of demolition works, a full review of heritage features and areas within the CPO will be undertaken with the contractor and the Project Built Heritage Specialist (refer Section 9.1). Following this, the written demolition methodology and salvage strategy will be agreed. The key focus for the demolition methodology and salvage strategy will be the extent of floor removal within the CPO, and the ability to reuse materials from the raised central timber floor.

4.2

Building Record Methodology

The following recording level has or will be undertaken for the CPO building: a b c d

Comprehensive measured drawings of all elevations – internal and external, cross-sections, floor plans, roof plans, reflected ceiling plans, mouldings and other details.

Comprehensive written records, including detailed stratigraphic recording and matrices.

Comprehensive photography of all contextual views, elevations, spaces, fixtures and other features, incorporating the use of high or medium format photography.

Selective sampling of relevant materials where required by the Project Built Heritage Specialist.

Recording Techniques and Standards This section identifies the minimum standards for recording the features of the CPO during the Project.

The recording will be carried out under the supervision of the Project Built Heritage Specialist.

Recording techniques will include the production of drawn, written, and photographic records as noted above.

•

Measured drawings will systematically gather evidence about a place, and convey accurate visual information about its current format.

•

Written records enable more detailed evidence to be captured, including the composition and finish of materials, the configuration of stratigraphic relationships (such as through stratigraphic matrices) and other aspects of chronological development.

•

Photographic recording is a rapid way of capturing descriptive information, and usefully conveys aspects of visual appearance.

Measured Drawings A comprehensive set of measured drawings (foundation, floor and roof plans, elevations and sections) will incorporate all relevant elements that contribute to an understanding of the CPO,

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13 construction, development and use of the structure, including structural material, decorative elements, and information relating to alteration and wear.

The scale of measured drawings indicated in Table 4.1 is generally the minimum required. In many cases a larger scale will be necessary, particularly where significant details are small. It may be necessary to draw some perspectives, particularly internal elevations more than once as overlays, if different information appears during the course of the investigation.

It is important that the drawings accurately depict the material that exists rather than display an idealised version through the use of artificially straight lines, level planes or exact right angles.

In some instances, a survey may be required to ensure appropriate levels of accuracy. In some lower-level recording, artificially level planes (such as from a top plate or base plate) may be used.

Table 4.1:

Measured Drawings Recommended Scale

Floor plans

1:500 or 1:200 (showing overall layout, boundaries and topographic features in relation to main buildings) 1:50 or 1:20

Roof and ceiling plans

1:50 or 1:20 (showing disposition of roof/ ceiling timbers)

Elevations (interior/ exterior)

1:50 or 1:20

Sections

1:50 or 1:20 (across and along structure)

Joinery details

1:20 or 1:10

Other significant details

1:20 or 1:10

Moulding profiles

1:2 or 1:1

Phased plans and elevations

Scale flexible, as appropriate

Overall site layout

Written Records Generally, written records fall under two categories: descriptive (documentation of what is actually present) and interpretive (discussion of possibilities based on existing fabric but within the context of wider research).

Descriptive a b c d

e

General description of exterior - materials, methods of construction, dimensions, overall shape and form.

General relationship between the structure and it’s past and present setting (e.g. other buildings, curtilage layout, curtilage boundaries, gardens, access roads, streetscape etc.).

General description of interior, including overall layout.

Systematic description of each room/space, including architectural elements, decorative schemes, fixtures and fittings, evidence of use/wear and alteration. Information should include the description of materials, construction methods, visual appearance and dimensions as appropriate. Note: the attic and subfloor each count as a space, as does the exterior.

Index of all drawings, photographs, references/sauce material, finds and samples.

Interpretative a b

Detail the evidence for overall chronological development.

Outline evidence for original and changing use.

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14 c d e f

Discussion about the preparation of materials, sources and supply.

Comparison of earlier/original plans (if available) with the structure as built and as currently found.

Comparison of evidence with that from other known documentary sources e.g. photographs, sketches and written accounts.

Summary account of the preliminary phasing (incorporating plan, form, function and age), based on all of the above.

Written notes will be of archival quality, and will include a copy in non-digital format. Notes will usually be compiled in conjunction with detailed scale drawings, and should include the clear and systematic labelling of all information portrayed on such illustrations.

In complicated instances, or when dealing with fabric of outstanding or considerable significance, a full stratigraphic record of a structure, or part of a structure, may be of value, with pro-forma sheets for the description of each appropriate element, and a stratigraphic matrix detailing their chronological order. In many cases, an intermediate approach is likely to be sufficient, with separate descriptions and preliminary interpretations supplementing the other records. Accurate architectural terminology should always be employed if possible.

Photographic Recording/Photography Photography will be carried out using an appropriate camera. High resolution means that more detail can be captured.

Where substantially higher quality resolution or archival retention is required, medium or large format cameras and film are preferred. The processing of black and white film, as the most effective long-term archival record, requires particular care.

Colour print and digital photography are generally not currently considered to be archivally stable, but can be usefully employed for aide-memoire or presentational purposes.

Table 4.2 outlines the camera angles and other techniques that are required to record the various heritage aspects of the CPO. Table 4.2:

Camera angles

Contextual

Views showing relationship to setting, other buildings or significant viewpoints (e.g. streetscape, yards, gardens, boundary walls)

Exterior

Principal elevation (frontage), Other elevations Significant features (structural or decorative, roof, signage, evidence of modification etc.)

Typical details (chimneys, doors, windows, fixtures and fittings, eaves, weatherboards)

Interior

Rooms (including roof space, attics, subfloor areas, basements) Features (staircase, fireplaces etc.)

Significant elements (stained glass, tiles, plaster, wallpaper, wear marks, fixtures) Typical details (doors, architraves, windows, fittings)

Other Techniques

Removal or test scraping of accumulated material to determine sequence of alterations.

Excavation of associated in-ground material, including earlier floor surfaces, foundations and services.

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4.3

Salvage Strategy Methodology

The following section sets out general procedures for the removal, storage and later refitting or reuse of elements of the CPO affected by the construction works.

Elements to be removed and stored It is expected that most elements will be kept in place and protected where damage from construction work is a risk.

Currently it is proposed that two areas of the CPO will require elements to be removed prior to the commencement of construction works in the building: a b

The raised timber floor within the ground floor of the CPO; and The main entrance stairs on the Lower Queen Street elevation where four wrought iron light stands on either side of the stairs will be removed and stored, and three full flight of stairs removed to allow construction of a ground beam.

The raised timber floor incorporates the original re�cycled jarrah flooring from the banking chamber and kauri flooring from the original building. The jarrah is to be salvaged for reuse on the column plinth tops and as a dado rail on the external walls. The kauri flooring does not have a specific end use, but will also be salvaged.

The two outer flights of stairs are Coromandel granite slabs or blocks, with tiled nosing set in a rebated edge. The lower two steps of the central stairs appear to be tiled (modern) possibly over a concrete substrate. The blocks will need to be carefully cut with a diamond saw at the ends and underside to be removed. The concrete steps could be broken out and reformed to match existing.

Removal of stairs involves cutting and prising the blocks from the concrete base. To inform their removal, a sample area was undertaken with the removal of a step from the top of one flight. The sample work was reviewed by Mr George Farrant (Auckland Council Heritage Advisor), Mr Jeremy Salmond (CRL Heritage Advisor) and Antony Matthews (MMA). Based on this successful trial, all blocks have now been removed without breakage or damage.

These elements will be stored in an appropriate location, either in the upper levels of the CPO building or a secure location off-site. The storage location will be confirmed prior to the removal of these elements from the CPO 6. Should the elements be stored in the CPO building, engagement will be undertaken with the CPO long-term lessee, Cooper and Company, in this regard.

The removal of these elements will be undertaken by appropriately trained contractors after a methodology is agreed with the Project Built Heritage Specialist. The contractors responsible for dismantling heritage elements of the CPO will also be responsible for the reinstatement works following the completion of construction.

Refitting of elements following construction The main entrance stairs to the CPO on the Lower Queen Street elevation and the four wrought iron light stands on either side of the stairs will be reinstated following the completion of the Project construction works.

The replacement steps with be reconstructed based on the existing layout (as agreed by the Project Built Heritage Specialist) using selected Coromandel granite to match existing steps.

The stairs are to be stored at Croatian Tilers yard (the contractor responsible for their removal), where a new nosing edge will be installed.

6

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4.4

Column Recording

As described in Section 3.1, the concrete encasing several of the columns in the CPO Building will need to be removed to expose the steel columns and allow for underpinning collars to be fixed to the columns.

Every column will need to be measured and recorded prior to demolition works. For this a 3-D scan will be taken of each of the columns.

The methodology for reinstatement of these columns following construction is yet to be confirmed.

4.5

Building Record and Salvage Strategy Report

In January 2017, prior to commencement of demolition works, Matthew and Matthew Architects completed the building record (incorporating a written record, measured drawings and photographs), and salvage strategy for the CPO Building in accordance with the methodology described in Sections 4.2 and 4.3 of this DWP (Appendix F).

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5

Monitoring Methodology

The Project works have the potential to result in damage to the built heritage values of the CPO or adjacent heritage buildings which are identified in Section 2.1. This section outlines the proposed methods for monitoring building damage.

5.1

Monitoring Prior to and During Construction

In accordance with the Project Structural Design Drawings (refer to Table 5.1) and from the results of the pre-construction survey reports, geotechnical and structural instrumentation will be installed on surfaces of, or nearby to, existing structures, inclusive of the CPO. In some instances, this will include instrumentation installed within the property as well as on the external surfaces of the property with the property owner’s consent. Settlement monitoring will also be undertaken at multiple locations in lower Queen Street, Galway Street and Tyler Street during the Project.

Table 5.1:

Relevant Monitoring Detail Drawing references

Drawing Reference

Drawing Title

CRL-BTM-STR-000-DRG-2041

CPO and Queen Street Monitoring Requirements

CRL-BTM-STR-000-DRG-2042

CPO and Queen Street Monitoring Positions Basement Plan

CRL-BTM-STR-000-DRG-2043

CPO and Queen Street Survey Monitoring Positions Plan Middle Strut

CRL-BTM-STR-000-DRG-2044

CPO and Queen Street Monitoring Positions Steel Underpinning Beams

CRL-BTM-STR-000-DRG-2045

CPO and Queen Street Monitoring Positions Concrete Underpinning Beams

CRL-BTM-STR-000-DRG-2046

CPO and Queen Street Monitoring Positions Façade Elevations

CRL-BTM-STR-000-DRG-2047

CPO and Queen Street Settlement Monitoring

While most of the monitoring instrumentation will be permanently installed at monitoring locations, some instrumentation will be portable for specific event monitoring, such as seismographs used to monitor works vibrations.

The purpose of this instrumentation will be to measure any movement, settlement, tilt, strain and induced vibrations as a result of excavation and construction works which may have the potential to adversely affect the structure. The instrumentation will be installed prior to starting the construction works. This will allow a period where initial readings and baseline monitoring readings from the instrumentation can be obtained in order to provide a reference data set (or ambient in the case of vibration and noise).

In addition to the geotechnical and structural instrumentation that will be installed by the Instrumentation Specialist in accordance with the contract drawings and as a result of the preconstruction surveys, the contractor shall install additional instrumentation required to monitor a particular structure which may be affected by construction works and methods.

The routine monitoring frequency and duration will depend upon the location of the Project works at any time. The proposed monitoring frequency and duration of the geotechnical and structural instrumentation installed on or near historic resources/structures is described in the Groundwater Settlement Monitoring and Contingency Plan (GSMCP), which is required under Condition 117 of the Water Permit R/REG/2014/5432 for the Project.

Additionally, a programme of building condition surveys is also required under Condition 46 of the CRL designation and Condition 31 of the BTC designation. This monitoring is outlined in Section 6 of this DWP.

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6

Pre and Post-Construction Surveys of Built Heritage

6.1

Pre-Construction Surveys

A pre-construction inspection of heritage buildings (inclusive of those buildings listed in Appendix 1 of the BTC designation conditions and Appendix 2 of the CRL designation conditions) will be undertaken as part of the Project works. The condition assessments will ascertain any pre-existing damage to a building, existing structural distress, and any potential weakness of the structure’s foundations or structural elements, as well as non-structural damage (refer to Section 4 of this DWP for recording requirements).

The nature of the pre-construction surveys will depend on the type and size of the structure to be surveyed, and the location of the structure, with respect to the designated influence zone associated with the Britomart Station construction site, as follows: • •

•

6.2

In the case of CPO, the interior survey shall be extended to include all interior floors.

Additionally, a post-construction survey will also be completed.

The survey shall comprise a repeat of the required elements of the pre-construction survey so that a direct comparison can be made. This survey shall be carried out only following a direct specific instruction by Site Manager in consultation with the Project Built Heritage Specialist.

In more detail, the survey of identified significant heritage fabric will include a complete exterior and interior survey. Installation of exterior crack monitors shall be required on readily accessible existing exterior cracks greater than 2 mm in width, and selected interior cracks, as determined in consultation with the Project Built Heritage Specialist.

Photographic (or Video) Documentation

The contractor will document, using photographic means (and video if appropriate), any potential weakness or signs of structural distress, during the inspection of the CPO during the pre-construction survey. Detailed notes will be recorded and, where applicable, sketches will be made to document the condition of the structure.

Damage or deterioration of a non-structural nature will also be recorded, again using photographs (or video recording). An assessment of the stability of any applied decorative ornaments or features, together with a procedure addressing any recommended remediation to secure or mitigate potential problems prior to the commencement of any construction activities, will be recorded for inclusion in the report documentation.

The location of all cracks greater than 2 mm in aperture width, shall be recorded with a positional accuracy of +/- 200mm. Installation of grid crack monitors may be required on selected readily accessible cracks with an aperture width greater than 2 mm discussed above and as determined by the Contractor in consultation with the Project Built Heritage Specialist.

Photographic Technical Requirements Photographic requirements for the building surveys are as follows: •

General Images - conventional (digital) photography will be used with appropriate professional lenses capable of producing high resolution 1- 2Mb JPEG images.

•

Archival Images - conventional (non-digital) photography will be used, using a medium format camera with appropriate professional lenses capable of producing 2.25 x 2.25 inch black and white negatives.

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19 Interior details and subsurface photographs may be taken using a conventional (non-digital) professional grade camera with appropriate professional lenses capable of producing 35 mm colour or black and white negatives.

Video equipment shall be high-resolution (broadcast quality), with low light capabilities although additional lighting may also be required.

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7

Protection Methodology

This section outlines the methodology for protecting the key heritage features and finishes of the CPO during construction of the Project.

Given the nature and scale of the proposed works, together with the management proposed by this and other relevant DWPs (refer Section 7.6 below), it is not anticipated that the surrounding heritage buildings or structures outlined in Section 2.1 of this DWP will be adversely affected during the construction works. As such, protection of these structures will be achieved through the proposed design, construction methods and monitoring detailed in Section 5 of this DWP and elsewhere. Should monitoring indicate that additional building specific protection is required, the form of protection will be confirmed by the Project Built Heritage Specialist on a case by case basis.

7.1

Overview of Protection Methodology for CPO

All work involving historic buildings or structures, such as the CPO, requires proper planning and the implementation of appropriate protection measures in order to minimise damage or impacts on historic fabric or finishes. This includes: •

Protection of any chattels (movable items) where present;

•

Protection of historic architectural features and finishes;

•

Fire protection and security;

•

Managing damage from vibration, ground movement or water ingress; and

•

Monitoring and supervision of sensitive works.

7.2

Protection Methodology for Specific CPO Exterior and Interior Features

As outlined in Section 4.2 of this DWP, moveable chattels will be removed from the areas of the CPO subject to construction works and appropriately stored until they are reinstated towards the end of the works. Specific provisions for the reinstatement of the CPO’s key heritage elements is also outlined in Section 11 of this DWP (and described in detail in Appendix G, along with the Revised Conservation Plan for the CPO (2003)).

This section outlines the key exterior and interior features of the CPO that are not able to be removed from construction areas, but that will require specific protection should construction works be undertaken near or adjacent to these features. Protection measures have been confirmed by the Project Built Heritage Specialist, following a review of the final CPO construction methodology (Section 4.0, Appendix F). All protection methods to the following features shall be assessed and signed-off by the Project Built Heritage Specialist.

CPO Exterior Features Table 7.1 outlines the protection, and protection measures required, for the CPO’s exterior heritage features.

Table 7.1:

Protection of Exterior CPO Heritage Features

Feature

Protection

The exterior stone and rendered elements and surfaces of the CPO

•

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If works are proposed near or adjacent to these elements and surfaces, plywood protection to a minimum of 2 metres will be required.

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21 Feature

Protection

The front stairs of the building onto lower Queen Street and pylons with lamps located on either side of the stairs

• These features will be removed prior to the commencement of the construction works and stored for reinstatement following the completion of construction.

• The remaining elements will be appropriately supported and protected against any potential cracking or breaking of Coromandel granite panels

Building canopies on the lower Queen Street frontage that extend over the northern and southern building entrances

• These will be protected against machinery movement during the works.

• Removal of the north canopy was required to allow access for the D-wall excavation and guide wall construction. Glass soffits, bronze lay light frame and bronze fascia panel will be removed prior to the commencement of the construction works and stored for reinstatement following the completion of construction.

CPO Interior Features Table 7.2 outlines the protection measures required, for the CPO’s interior heritage features not addressed by the Project’s salvage strategy.

Table 7.2:

Protection of Internal CPO Heritage Features

Feature

Protection

CPO VESTIBULE/OFFICE FLOORS The main vestibule of the CPO (inclusive of the mosaic floor, tiled walls, stairs, the timber door frame and highlight to the main ground floor space (and construction site))

• This area will be used during construction for staff access to upper floor site office. However, it is not to be used for construction access and the doors to main site area are to be closed at all times.

• This area will have appropriate wall, floor and element protection to all surfaces, and access limited to essential activities only. The foyer/vestibule areas on the upper floors of the CPO will also be protected (refer below for detail of proposed protection).

Mosaic Floor

• Carpet matting laid on ground and first floor level

Tiled Walls

• Self-supporting plywood lining fitted to 2.4m high 7

Stairs

• Plywood fitted to cover ceramic tiles to dado height wedged against stainless steel handrail • Stairs cleaned twice a day during construction.

Timber door frame and highlight to the main ground floor space

• Self-supporting plywood lining fitted to 2.4 m high. Top of plywood to be cut short of beams above (nominal 50mm) to prevent damage to beams.

First floor

• First floor southern/northern end is being used during the works as the project office. No construction activities required at this stage. Structural support to front (west) wall may necessitate protection works. This is to be determined once the design has been confirmed.

Timber floors

• Carpet protection laid over timber floors on first floor

Plywood protection was removed to lobby wall tiling in 2018 for inspection by MMA. Photographs were taken, tiles cleaned and plywood protection replaced. No additional defects noted.

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22 Remaining areas of the upper floor of the CPO

• If used during construction, these areas will need to have appropriate wall, floor and element protection to all surfaces.

MAIN CONCOURSE SPACE Steel framed windows exterior walls

• Plywood fitted to timber frame. Timber frame bolted to concrete shear panels fitted 2003.

Free standing columns

• Where practicable, plywood fitted to self‐supporting timber framing around columns. Polystyrene protection placed between timber frame and columns.

• Plywood protection to some columns has been removed as work progressed to allow construction access adjacent to columns Where plywood was removed the columns have been wrapped with plastic bubble wrap to protect from dust and debris.

• Further plywood protection has been removed to allow for the underpinning support structures to be fixed to the columns. This has required further removal of the lightweight concrete encasement of the steel columns. Prior to removal the ground floor space was digitally scanned to record the size and configuration of columns to facilitate reinstatement on completion.

Flat ceilings and beams to the perimeter areas

• Ceiling and beams between columns to be protected with plastic shrink wrap.

• 90x45mm timber battens to be screw fixed into flat ceilings either side of beams into ceiling joists above. (Note all ceilings are 2002‐ 2003 fire rated plasterboard linings). Shrink wrap to be fixed to timber battens, and held in place with fixing batten over back batten.

Decorative ceilings, beams and domes in central area (former Banking Chamber area)

• It is expected that the construction works will be at a level sufficiently below the banking chamber to have very little potential effect on this area.

• Ceiling and beams between columns to be protected with plastic shrink wrap. This will be fixed below the ceiling to framing spanning between the ply boxing fitted around the columns.

• 2/125x65mm steel channels to be fixed either side to top of ply column boxing to span between columns. 90x45mm bracing fitted between. 90x45 timber plates to be fitted to channel to take shrink wrap. Support frames set below beams so shrink wrap runs below beam level throughout central area.

The green tiles located on the “Banking Chamber” face of the main vestibule

• These will require full surface protection during the Project construction works.

Loading bay access

• Change of access from the north bay on the east elevation to the north entry on the west elevation (where the heritage canopy has been removed). No impacts on heritage elements. Plywood protection in place to granite clad doorways surrounds. Non original 2002 granite steps protected with plywood.

BASEMENT Basement area under the entrance lobby

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• The original stairs remain below the lowered floor added in 2002, as well as wall tiling matching the main lobby and white tiles to walls where the pavement lights were located.

• As the walls need to be scabbled back for a key, all tiles and the remnant stairs and door architrave are to be removed.

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23 • The extent and general layout of this removal has been photographically recorded. Sample tiles, and a section of the architrave has been retained onsite and is stored on the first floor.

7.3

General Protection of Historic Interior Features and Finishes

Table 7.3 outlines the general protection measures for historic interior features and finishes that shall be adopted and implemented as appropriate during construction.

Table 7.3:

Protection of Interior Features and Finishes

Feature/Finish

Protection

Less movable architectural material or finishes

• Materials and finishes such as plaster mouldings are often best retained in place.

• Depending on the final construction methodology, some materials or finishes may require custom-designed protective measures developed and monitored by the built heritage specialist.

Access by construction personnel to spaces with significant heritage features and finishes

• Access shall be restricted to the extent practicable, except for specific work requirements.

• Where it is not possible to restrict access to interior spaces with historic features/finishes these shall be physically isolated from construction works to avoid or minimise physical/vibration damage from construction.

• Typically, this will apply to walls with historic wall coverings (up to around 2 m in height), fragile ornamental ceilings, staircases and floors. Such features, should be isolated by means of protective barriers and coverings.

Retained Flooring

• Retained flooring shall be protected from damage caused by abrasion, falling objects, dust and dirt, and spilled liquids.

• If work in, or traffic through, a particular space does not involve one or more of these risks, temporary protection measures may be reduced.

Damage to heritage features and finishes caused by abrasion

• This shall be controlled by means of protective coverings, such as canvas tarpaulins, high density plastic or resilient wood fibre panels. Canvas or plastic covering should overlap and be taped at all joints.

Resilient wood fibre panels

• These shall be carefully fitted with tight seams and laid continuously wall to wall. Joints shall be taped to avoid displacement of the panels after setting and the fire safety confirmed to ensure fire loading is not affected.

Protection to finishes from spilled liquids

• Where protection from spilled liquids is required, a layer of polyethylene sheeting shall be applied under a plywood top layer.

• Care shall be taken during assembly to ensure that moisture from spilled liquids is not trapped against the historic fabric. Otherwise, the staining, splitting, wood-grain raising, or stone-finish destruction could potentially go undetected for months while concealed from view under the protection assembly.

• Care shall also be taken to avoid sheet coverings, such as building felt, which could potentially stain historic flooring.

Wall protection

• Where required, wall protection is typically fabricated from fire-retardant treated plywood attached to wood framing. The assembly shall be selfsupporting and self-bracing, secured at its base to the floor protection assembly.

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24 Feature/Finish

Protection • Struts and supports shall be provided, as required, to brace the assembly without installing fasteners into any historic fabric. Careful assembly includes using screw fasteners in order to eliminate hammering during assembly and ripping damage during disassembly.

• Where wood framing, furring, or panels abut historic wall materials, the back side of the protective assembly should also be padded using strips of neoprene or strips of Pinex Board, glued to the protective assembly member.

Historic stairways, balustrades, landings, door surrounds, window surrounds,

• These shall be protected from construction damage by combining the techniques described for floors and walls. Horizontal surfaces should be protected as floors, and vertical assemblies treated as walls, with the major difference being the complexity of the framing required.

Masonry

• The management of construction moisture on masonry from activities such as drilling and concreting shall be assessed by the Project Built Heritage Specialist prior to the commencement of construction and measures implemented to minimise impacts on the CPO masonry as appropriate.

7.4

Fire Protection

The heightened possibility of fire accompanies many demolition and new construction activities.

Temporary heating devices, torches, sparks and undersized electrical utility panels are common sources of fire at construction sites. Additionally, the improper storage of fuels, cloth rags and brushes also presents opportunities for fire to ignite and spread.

Cutting and welding in the CPO shall be undertaken with appropriate supervision, fire watches, and emergency fire protection apparatus in accordance with the Project hot works procedures to ensure the potential for fire in the building is avoided. Cutting and welding will be controlled by requiring a new permit each day, issued by the general contractor or construction manager, for each location where cutting or welding is to occur. A permit will not be issued until the following conditions are satisfied: 1 2 3 4 5

There is no possible alternative of less risk; It has been determined that cutting and welding can be safely conducted at the desired location; Combustibles have been moved away or safely covered; Fire watchmen with extinguishers are posted for the duration of the work and for 30 minutes after work completion; Cutting and welding operations cease two hours prior to the close of construction each day to minimize the risk of undetected smouldering fire.

Prior to the commencement of construction works, access paths for heavy firefighting equipment are to be identified, including free access from the street to fire hydrants outside the site, agreed with the fire service and maintained.

In line with current workplace safety, smoking will not be permitted anywhere on the site. This will be strictly enforced as a priority of the construction manager.

7.5

Security

The security of a historic building can be threatened when construction provides opportunities for illegal entry. External entrances shall be secured as appropriate for construction activities over the course of the Project.

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7.6

Managing damage from vibration, ground movement or water ingress Vibration

Demolition and new foundation work are common sources of vibration that can affect adjacent historic structures. The tools and methods used in demolition, such as impact hammers and concrete breakers, produce vibrations that may be transmitted to the structure. These matters are addressed in the Project Construction Noise and Vibration DWP (refer to Appendix F of the Project CEMP).

Ground Movement Excavation and foundation work can also cause ground displacement and movement of adjacent historic structures. New construction almost invariably requires the digging of foundations much deeper than the foundations of neighbouring historic buildings. A historic structure, with shallow masonry and wall footings, may experience corresponding displacement that can result in major structural damage. Managing the risk and potential effects of ground movement or settlement is addressed in the Project Groundwater and Settlement Monitoring and Contingency Plan (GSMCP) (refer to Appendix O of the CEMP).

For the CPO works, significant works will be undertaken to underpin and strengthen the building foundations, hence enabling the rail tunnel excavations under the building. Significant monitoring of ground and building settlement will be undertaken, as described in the GSMCP, to ensure that any settlement with the potential to result in building damage is detected early and contingency measures adopted where needed.

Water Ingress A well-functioning water drainage system is essential to the protection of any historic structure. This system can easily be rendered ineffective by construction or demolition work. Debris originating at the construction site often finds its way to the gutters, downspouts and drains of an adjacent building. Regular inspections of the stormwater drainage system (kerbs/drains) will be undertaken as part of the weekly site inspection. In addition, controls around dust, and water quality should limit the potential for effects on the drainage systems of neighbouring buildings (e.g., by requiring no effect beyond the site boundary).

7.7

Monitoring and Supervision of Sensitive Works

The Project Built Heritage Specialist will be required on-site to monitor sensitive works and advise the contractor around avoiding or minimising adverse effects on the built heritage values of the CPO. Specifically, the monitoring and supervision by the Project Built Heritage Specialist will be required at the following times during the Project: •

Removal of the raised timber floor within the ground floor of the CPO outlined in Section 4.2 of this DWP;

•

Removal of the four wrought iron light stands on either side of the stairs and the three full flight of stairs outlined in Section 4.2 of this DWP;

•

Installation and assessment of heritage protection measures outlined in Section 7.2 and 7.5 of this DWP; and

•

Should any unexpected built heritage related issues arise or new protection measures be required.

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26 In addition to the above, the Project Built Heritage Specialist will provide the Project team with a briefing on this DWP and appropriate training in relation to the heritage features and values of the CPO as outlined in Section 9 of this DWP.

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8

Rectification Methodology

The rectification methodology, both at a broad and detailed level, has been discussed extensively with HNZPT and Auckland Council, and has been described in detail as part of the Agreement under the Covenant for the CPO (Refer to Section 11 of this DWP). It is expected that much of the construction works will involve rectification directly associated with significant built heritage fabric with site specific agreements made on site between all parties if unexpected issues arise. It is also expected that there will be no rectification works required beyond areas directly affected by construction works (refer to Section 4.2 of this DWP). The condition assessments required in the CRL and BTC designations will be the vehicle for any discussion around the need for rectification works, and it is likely that this will be undertaken on a case by case basis, when the post-condition assessments are undertaken. Specific rectification methodologies will be guided by the ICOMOS NZ Charter and the policies outlined in the Revised CPO Conservation Plan (2003), and agreed with the Project Built Heritage Specialist before works begin.

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9

General Matters

9.1

Project Built Heritage Specialist roles and responsibilities

The Project Built Heritage Specialist will be responsible for ensuring that the requirements set out in the Built Heritage Section of the Historic Heritage DWP are fulfilled. This includes ensuring that the necessary monitoring, investigation, recording, and consultation is undertaken and that the contractor’s site safety requirements are followed.

9.2

Contractor briefing

Prior to the start of construction works, the Project Built Heritage Specialist will meet key construction and demolition contractors on site, to brief them on the built heritage requirements for the Project.

9.3

Training

Prior to the start of earthworks, the Project Built Heritage Specialist will provide a briefing to the contractor on the built heritage requirements, including statutory requirements under the HNZPTA, how to recognise heritage material if exposed during construction, what actions need to be taken, and who to contact if the Built Heritage Specialist is not present on-site.

9.4

Recording and Supervision

The Project Built Heritage Specialist should be given at least 2 weeks’ notice by the lead construction contractor that works are about to begin. The construction contractor will keep the Project Built Heritage Specialist informed as to the work schedule, and any changes that may arise.

The construction contractor will give the Project Built Heritage Specialist sufficient time and opportunity for the recording and/or sampling of any elements, and will cease works in the immediate vicinity until this work is completed.

The Project Built Heritage Specialist will be required to supervise and monitor sensitive construction activities, particularly in the CPO, and advise the contractor in relation to construction works that may result in adverse effects on the built heritage values of the CPO and measures to be implemented in order to avoid or minimise such effects. Refer to Section 7.7 for further detail in this regard.

9.5

Contact details

The contact details of the Project Built Heritage Specialist, Auckland Council Heritage and Heritage NZ are outlined in Table 9.1.

Table 9.1: Contact details Project Built Heritage Specialist

Antony Matthews

027 291 2047

antony@mmarchitects.co.nz

Heritage Built Specialist Auckland Council Auckland Council Compliance and Monitoring Officer

Bryan Bennett George Farrant Tim O’Grady

(021) 227 8995 (207) 532 7726 (021) 834 584

Bryan.Bennett@aucklandcouncil.govt.nz George.Farrant@aucklandcouncil.govt.nz

Built Heritage Adviser HNZPT

Robin Byron

(09) 307 9928

rbyron@heritage.org.nz

Historic Heritage Delivery Work Plan – Built Heritage

Timothy.OGrady@aucklandcouncil.govt.nz

July 2018

29

10

Communication and Consultation

The Project Built Heritage Specialist will facilitate any consultation with HNZPT, the Auckland Council Built Heritage Unit in relation to the management of built heritage. This will be primarily through attendance and presentations to the Heritage Advisory Group (HAG) on a monthly basis. Evidence of this consultation will be provided by the Project Built Heritage Specialist to the Project team in their monthly site monitoring reports.

Consultation with the CPO long-term lessee, Cooper and Company, will also be undertaken in relation to the management of CPO heritage fixtures. Communication with the general public will likely be in relation to measures being implemented during construction to avoid or minimise impacts on key heritage features and values of the CPO, such as the salvage strategy and protection measures.

The continuation of regular meetings with HNZPT and the Auckland Council Heritage Unit (Built Heritage and Implementation), will ensure that any issues are addressed in a timely and transparent manner. Engagement will include regular updates on progress, site visits at significant occasions, and in the event of unexpected finds or changes to agreed methodologies both within and outside the Agreement under the former CPO Covenant. This could also include periodic publication of findings or the result of historic research.

Historic Heritage Delivery Work Plan – Built Heritage

JUNE 2016

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11

Heritage Covenant – Reinstatement of Heritage Elements

The CPO is subject to a Deed of Heritage Covenant dated 18 July 1995 and registered against the title of the CPO, being Computer Freehold Register 93982, memorial C891516.1. Pursuant to the Deed of Heritage Covenant, works may not be undertaken affecting the primary or secondary features identified in the Deed of Heritage Covenant without obtaining the prior written consent of HNZPT, who may impose reasonable conditions on such consent.

An Agreement will be signed with HNZPT prior to the commencement of works, to record the consent for the purposes of the Deed of Heritage Covenant, to complete the proposed works, and to record the conditions on which such consent has been given. This agreement is contained in Appendix G. All works within the CPO, and all reinstatement works will be undertaken in accordance with the requirements of the agreement and plans provided in Appendix G and the CRL ‘Britomart Station Permanent Works’ detailed design drawings (18th December 2015). In particular the following drawings: •

CRL-BTM-ARC-000-DRG-2132 Rev D – CPO Permanent Works, Ground Level

•

CRL-BTM-ARC-000-DRG-2332 Rev B – CPO Permanent Works, Demolition Plan, Ground Level

•

CRL-BTM-ARC-000-DRG-2432 Rev B – CPO Permanent Works, Structural Set-out, Ground Level

•

CRL-BTM-ARC-000-DRG-3132 Rev B – CPO Permanent Works, Reflected Ceiling Plan, Ground Level

•

CRL-BTM-ARC-000-DRG-3231 - 34 Rev B – CPO Permanent Works, Reflected Ceiling Plan, Ground Level

•

CRL-BTM-ARC-000-DRG-4001 Rev D – CPO Permanent Works, Overall Long Section (E-W).

11.1

Proposed Reinstatement Works Entrance Vestibule and Stairway (Heritage Core)

The heritage vestibule (identified in the Conservation Plan as forming the “heritage core”), shall be retained at current levels. The floor, wall and ceilings treatments will be retained and conserved. It is acknowledged that as part of the works it will be necessary to temporarily remove the parts of the entrance stairs to the CPO in order to construct underpinning / strengthening beams. The entrance stairs to the CPO will be fully reinstated at the conclusion of the works.

CPO Ground Floor - General a

b c

The overall design including materials, symmetry, colours and textures used throughout the ground floor area of the CPO shall reflect heritage values of the building and associated elements as far as practicable. It will also endeavour to preserve the spatial identity and quality of the original components of the Banking Chamber.

Materials used in the alterations to the CPO as part of the redevelopment of the Britomart Transport Centre in 2002-2003 will be reused where appropriate.

All services will be concealed where practicable.

Banking Chamber Ceiling The leaded glass domes and ceiling treatments will be retained in situ and conserved.

Historic Heritage Delivery Work Plan – Built Heritage

July 2018

31

Banking Chamber Public Space a b c d e

The floor level of the Banking Chamber may be lowered to align with the current ground floor level of the CPO. The location of the original Banking Chamber Public Space and Banking Counter shall be indicated by a clear delineation within the ground floor space.

The level of the original Banking Chamber floor shall also be indicated on the perimeter wall of the CPO ground floor using a timber inlay.

Any existing materials shall be re-used where practicable and appropriate.

The final format of flooring material, colours and textures will take into account the heritage significance of the CPO and, where practicable, reflect the materials originally used.

Column Bases The bases of the columns in the ground floor of the CPO will use encasement and treatment options in general accordance with the CRL detailed design drawings.

Retail and customer service areas a

b

Existing kiosks and customer service units on the ground floor of the CPO will be removed and replaced with glazed enclosures to better present the full Britomart Station Ground Floor volume, with the exception of spaces where the functionality does not lend itself to glazed partitions (e.g. customer services offices and kitchenette).

The design and scale of the retail units on the western wall of the Britomart Station Ground floor (adjacent to the Entrance Vestibule), shall be appropriate to ensure the heritage values of the Banking Chamber Public Space are not reduced. Retail activities will not extend beyond the boundaries shown on the CRL detailed design drawings.

Ticket Gateline The rail ticketing gateline will be relocated from track level to the Britomart Station ground floor level as shown on the CRL detailed design drawings.

Openings into Tyler and Galway Street a

b

The existing building openings to Galway Street and Tyler Street may be closed off or glazed to enable the relocation of customer service facilities and/ or retail activities within ground floor of the CPO. There will be no new openings installed on the ground floor of the CPO to access Tyler and Galway Streets.

Signage Retail signage and customer information systems shall be designed in a co-ordinated manner in accordance with a signage protocol. CRLL will consult with HNZPT and the CPO long-term lessee, Cooper and Company, in the preparation of signage protocol for the CPO.

Heritage Interpretation Strategy A heritage interpretation strategy shall be prepared including recommendations about interpretative media (e.g. signs, plans, photographs, digital and other media). AT will consult with HNZPT in the preparation of the heritage interpretation strategy.

Historic Heritage Delivery Work Plan – Built Heritage

JUNE 2016

32

Plan The works to the Britomart Station Ground Floor will be carried out in general accordance with the CRL detailed design drawings.

Historic Heritage Delivery Work Plan – Built Heritage

July 2018

33

12

Review and Updating of the DWP

The Built Heritage Section of the Historic Heritage DWP has undergone a review process with the Community Liaison Group (CLG) established for the Project and a suitably qualified independent peer reviewer. An explanation of how any comments from both the CLG and Peer Reviewer have been addressed is provided in Appendix F.

12.1

DWP Review

The Built Heritage Section of the Historic Heritage DWP will be reviewed throughout the course of the Project: a b

To reflect material changes associated with changes to construction techniques, the natural environment or due to unresolved complaints; and As part of the annual management review of the DWP.

The management review of the Built Heritage Section of the Historic Heritage DWP will be undertaken at least annually by the Project Management team and the CRLL representatives. The management review will be organised by the Environmental and Sustainability Manager and the Project team will be informed of any changes to this Section of the Historic Heritage DWP through the regular Project communications processes. The review will take into consideration: •

Compliance with the designation or consent conditions, the CEMP, DWPs and EMPs (including site specific plans) and material changes to these plans.

•

Any significant changes to construction activities or methods.

•

Key changes to roles and responsibilities within the Project team.

•

Changes in industry best practice standards.

•

Changes in legal or other requirements (social and environmental legal requirements, consent conditions, CRLL objectives and relevant policies, plans, standards, specifications and guidelines).

•

Results of inspections, monitoring and reporting procedures associated with the management of adverse effects during construction.

•

Comments or recommendations from Auckland Council regarding the CEMP, DWPs and EMPs.

•

Unresolved complaints and any response to complaints and remedial action taken to address the complaint.

12.2

DWP Updates

The process for updating the Built Heritage Section of the Historic Heritage DWP as a result of a material change to the Project or the annual review, is as follows (refer to CRL designation Condition 23 and BTC designation Condition 22 for further information): •

Any material change to this DWP must be consistent with the purpose and objective of the relevant conditions listed in Table 1.1 of this document.

•

Affected parties and the CLG must be notified of the review and any material change proposed to this DWP.

•

This DWP must clearly document the comments and inputs received from affected parties in relation to any material changes, along with a clear explanation of where any comments have not been incorporated, and the reasons why not.

•

Any material change proposed to this DWP shall be subject to an independent peer review as required by CRL Condition 11 and BTC designation Condition 12.

Historic Heritage Delivery Work Plan – Built Heritage

JUNE 2016

34 •

Any material change proposed to this DWP relating to an adverse effect shall be submitted for approval to Auckland Council Compliance and Monitoring Officer, at least 10 working days prior to the proposed changes taking effect. If any changes are not agreed, the relevant provisions of the RMA relating to approval of outline plans shall apply.

A copy of the original Built Heritage Section of the Historic Heritage DWP document and subsequent versions will be kept for the Project records, and marked as obsolete. Each new / updated version of the Built Heritage Section of the Historic Heritage DWP documentation will be issued with a version number and date to eliminate obsolete Built Heritage Section of the Historic Heritage DWP documentation being used.

A summary of the review process will be provided annually to Auckland Council and otherwise be made available on request.

Historic Heritage Delivery Work Plan – Built Heritage

July 2018

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13

Management and Control of Documents

All project documentation is created, reviewed, approved, issued, revised, retained, and superseded in accordance with the project’s Document Management & Control Plan, which includes the requirement for records of review and authorisation to be maintained.

The following project-specific documents need to be created to support the processes described in this plan: 1. Building Record and Salvage Strategy 2. Pre and Post Construction Building Condition Assessments 3. Building and Ground movement monitoring 4. Built Heritage Specialist Monitoring 4.1. Site inspection records 4.2. Monthly site monitoring report/consultation record 5. Contractor briefings on built heritage requirements 6. Method statements 7. Project Induction 7.1. Full Induction Presentation Content 7.2. Full Induction Register 7.3. Visitor Induction 8. Review 8.1. Annual review record

Historic Heritage Delivery Work Plan – Built Heritage

JUNE 2016

Appendix A:

ISCA Requirements

Table A identifies the ISCA Credit Requirements relevant to the Built Heritage Section of the Historic Heritage DWP and where they are addressed in the document.

Table A: ISCA Requirements ISCA Credit

ISCA Requirement *

Relevant Section of the Plan

Comments

HER-1 Level 1

Baseline surveys of existing heritage carried out

Part A Sections 2.2, 4, 6, Appendix B, Appendix C

Also refer to Project Built Heritage Specialist and Supervising Archaeologist CVs.

HER-1 Level 1

Community heritage values have been identified through consultation and integrated into surveys

Part A Sections 2.2, 3.1, 8, 11

Also refer to Community Liaison Group comments (Appendix G) and minutes of meeting with NZHPT and AT

HER-1 Level 1

Predictions for heritage impacts have been developed

Part A Sections 3.2.1.3, 7.1, 8

HER-1 Level 1

Measures to minimise impacts to heritage identified

Part A Sections 3.2, 3.2.1.3, 4.2, 7.1, 7.2, 7.2.4, 7.3, 9.1, 9.2, 9.3

HER- 1 Level 2

Community and key stakeholders have participated in the heritage surveys

Part A Sections 2.2, 3.1, 11.1.9

HER- 1 Level 2

Heritage values beyond those listed in registers identified, considered and addressed

Part A Section 2.2, Appendix C (General Areas 2, 4, 6, 8, 10)

HER- 1 Level 2

Signage and interpretative material describing heritage values are implemented

Part A Section 11.1.10

Also refer to Project Communication and Consultation Plan

HER- 1 Level 2

Partnerships with relevant stakeholders have been developed

Part A Sections 2.2, 3.1, 8, 10

Also refer to Community Liaison Group comments (Appendix G) and minutes of meeting with NZHPT and AT

* Refer to ISCA Rating Tool for full details of the requirement

Also refer to Community Liaison Group comments (Appendix G) and minutes of meeting with NZHPT and AT

Appendix B:

CPO Conservation Plan

Appendix C:

Specific heritage features of the CPO

This Appendix provides a summary of specific heritage features of the CPO building as outlined in the agreed Chief Post Office Revised Conservation Plan (2003). The full CPO Conservation Plan will need to reviewed by the contractor prior to the commencement of works to ensure Project personnel are aware of those elements within the building that are of historic value. Values have been assessed using a scoring protocol which describes primary spaces or building elements in UPPER CASE, while components of such spaces or elements are assessed in lower case as follows: •

A, a

items of exceptional significance

•

B, b

items of considerable significance

•

C, c

items of some significance

•

D, d

items of little or no significance or not relevant

•

intr

items which are intrusive on conservation values

1. Site / Setting

A

Vistas of the building from the public street, in particular views from Queen Street/QEII Square

a

Association with adjacent buildings (Tyler Street streetscape)

b

Association with adjacent buildings (Galway Street streetscape)

b

Customs Street East, and Britomart transport centre

b

Commerce Street and the Takutai Square area

b

2. Building - Exterior Features Roof

A

The roof is a primary element of the overall composition of a building. The original roof form of the building is intact, except for a roof structure that has been added to cover over the central light well, parapets hide all roof structures. Elements of the roof which have a bearing on cultural significance of The CPO include: Wireless Station a Additional new structures d New roof surface d Flat roof form a Wall Elevations A The external walls are primary architectural features of the CPO and, together with the roof, establish its architectural form and character. The façades of both the QEII Square/Queen Street, Tyler and Galway Street elevations are architecturally modelled, and each contributes to an understanding of the building’s architecture. The rear of the building looking into the delivery yard was altered when the Annex was added.

Features which have a bearing on cultural significance include: Rendered brick masonry façade to Galway & Tyler Streets a Rendered brick masonry façade, east wall b Steel framed windows a

3. Repair and Reconstruction of Exterior Detailing The exterior of the CPO has been repaired, and missing or substantially altered elements have been reconstructed. Much of this work was carried out as part of the recommendations of the 1995 conservation plan.

4. Exterior elements that have been restored, repainted and reinstated Some important exterior elements have been removed, restored and reinstated and include:

a

Light Standards

a

Clock

a

5. Interior – Features

Most changes that have affected the CPO since its construction have been alterations to the interior.

The original interior has been substantially altered by the refurbishment and integration into the Britomart Transport Centre. The most destructive alteration has been the removal and reinstatement of the ground floor. Beyond the “heritage core”, considerable alteration and loss of original fabric has occurred to facilitate its new use and accommodate structural re-strengthening.

6. Heritage Areas within the CPO The Heritage Areas refer to the “historic core” that has been established about the original stair foyers which rise vertically through the building, including the west stairs, stair foyer, a room to the south off the foyer, west corridor and associated offices to the east.

Walls

- plaster moulded - generally plaster on timber framing & lath

a c

Ceilings - moulded fibrous plaster

a

Floors - original strip flooring and sub-floor structure

a

Modern paint finishes

d

Cast iron baluster railings

a

Under stair panelling

a

Ceilings & scotia mouldings

a

Skirtings and architraves

a

Dado mouldings

a

Arch mouldings in foyer and corridor

a

Timber door frames and highlight windows

a

Modern Stairs

c

Modern Lifts

c

Modern swing doors

intr

Surviving steel windows (refurbished original)

a

Steel windows (new replica)

d

Original timber window sills (removed, stored and replicated)

a

7. General Areas These are the areas beyond the heritage core on all floors, where considerable alteration and loss of original fabric has occurred. These general spaces have been opened up to make clear floor plates, and utilised to accommodate structural re-strengthening. Some original elements have remained in these areas and have been restored, or modified by replication.

Walls - original finishes removed many to be covered by new shear walls

d

Ceilings – altered but original scotia moulding remain

a

Floors - original strip flooring and sub-floor structure

a

Surviving steel windows (refurbished original)

a

Steel windows (new replica)

d

Existing timber window sills (most original some repaired or replicated)

a

Shear walls

intr

Timber glazed screens at the east end of the CPO on the upper levels

a

Specific Features are noted floor by floor as follows 1. Basement - Heritage Areas The extent of the heritage area appears to be the stair / lift foyer. The basement was originally very utilitarian in character, and has undergone the greatest degree of change during the Britomart Transport Station modifications, which also uncovered an original ground light (inset into the pavement to allow light to penetrate to underground levels).

Specific items of note: Glazed tilework, skirting an dado (protected and in place)

a

Ground light with white glazed tiles

a

2. Basement - General Areas All areas outside the heritage core have been removed, and the basement incorporated with the original ground floor to make a double height space. Specific items of note: Foundation support structure (exposed presentation has c significance)

a

3. Ground Floor - Heritage Cores The spaces associated with the ground floor “heritage core� are the most significant because of the existing finishes and its recognisable association with the original building and its function. The form of each space and the material finished should be protected, conserved, and maintained at all cost.

Any alteration to this space must be carefully planned so the overall heritage value of the spaces are not reduced. Original elements have been left in place and protected. Specific items of note: Glazed tile work (green and cream

a

Moulded glazed tiles, skirtings, dado & architrave

a

Patterned tile work (relief work)

a

Timber window & door Joinery

a

Mosaic floor

a

Modern lifts

c

Modern stairs

c

4. Ground Floor - General Area This area has changed substantially with the lowering of the original ground floor area. The original ceiling, windows, and supporting columns, are the only original elements remaining in place in this area. Specific items of note: Plaster ceiling and glazed domes

a

Doric support columns (round and square type)

a

Raised floor section (comprised of salvaged Kauri & Jarrah – provenance unknown)

c

Exposed column steel (exposed presentation has c significance)

a

Retail Kiosks

d

5. First Floor - Heritage Core The first floor “heritage core� has undergone some alterations and reinstatement work to maintain its heritage character. Specific items of note: Mosaic floor

a

Missing corridor wall section

intr

Openings and architraves. (timber highlight over entrance to banking chamber

a

Modern stairs

c

Modern lift

c

6. First Floor - General Area The first floor area has been altered most original finishes have been removed. Shear walls will frame original window openings and architraves. Specific items of note: Doric supporting columns (some reconstructed)

a

Architraves and timber frames

a

7. Second Floor - Heritage Core The Second floor heritage core has been modified to allow for the new star and lift. Specific items of note: Timber door joinery with highlights

a

Stair Balustrade

a

8. Second Floor - General Area The second floor area has been altered and most original finishes have been removed. Shear walls frame original window openings and architraves. Specific items of note:

Doric supporting columns

a

Door/window architraves and timber frames

a

9. Third Floor - Heritage Core The third floor heritage core remains relatively intact and has been restored to its original layout with the exception of the new lifts. Specific items of note: Timber door joinery with highlights

a

Original plaster ceilings

a

Concrete ceiling structure

b

Modern lifts

c

Modern Stairs

c

Stair balustrade

a

10. Third Floor – General Areas The third floor was damaged by fire while the building was empty. All original fishes were removed.

Shear wall frame the original window openings. Specific items of note: Doric supporting columns

a

Door architraves and timber frames

a

Spiral stair (northern dome access – cast iron)

a

Modern spiral stair (southern dome access - modern)

c

11. Southern Domed Corner Tower No original fittings remain in this room. Specific items of note: Windows and sills

a

Modern Spiral stair

c

12. Northern Domed Corner Tower Some original fittings remain and some finishes. Spiral Stair access from the third floor has been retained. Specific items of note: Windows and sills (some reconstructed – d)

a

Spiral stair

a

13. Roof Structures Wireless room

a

Lift motor room

c

Roof over light well

d

Appendix D:

CPO Heritage Covenant

Appendix E:

CPO Diaphragm Wall Plan

Appendix F:

Building Record and Salvage Strategy

Appendix G:

Consent in principle to works within the provisions of the deed of heritage covenant dated 18 July 1995

Appendix H:

CLG and Independent Peer Review Comments

Community Liaison Group Comments

•

Comments received from the CLG are as follows: Date

CLG Member

Comment

Response

24th November 2015

Kathy Ross

Will there be a specific heritage contact person during the works?

Specific contact details will be included in final DWP – no change to the draft DWP

24th November 2015

Kathy Ross

How will you address water control given there are a number of old drains around buildings, many of which are unknown

Monitoring will be undertaken during construction as outlined in Sections 7.3.2 and 7.3.3 of the DWP – no change to DWP

14th April 2016

Cooper and Company

Section 4.2.1 notes that two areas of the CPO will be removed and stored but does not state where these will be stored. Offsite or upper levels of CPO? Cooper and Company are particularly interested in what activities are proposed to occur in the upper levels of the CPO.

Additional text included to state – “These elements will be stored in an appropriate location, either in the upper levels of the CPO building or a secure location offsite. The storage location will be confirmed prior to the removal of these elements from the CPO. Should the elements be stored in the CPO building, engagement will be undertaken with the CPO long-term lessee, Cooper and Company.”

14th April 2016

Cooper and Company

Section 7 - there are a lot of monitoring and protection measures proposed for CPO in the DWP – but there are no similar detailed measures proposed for other heritage buildings (other than condition surveys).

This section simply says that the form of any protection required for other buildings will be confirmed by the Project Built Heritage Specialist. It would be good to understand more about what monitoring, etc is proposed for other buildings.

As outlined in Section 7 of this DWP, given the nature and scale of the works, together with the management measures proposed, it is not anticipated that the surrounding heritage buildings or structures will be adversely affected during the construction works. Protection of these structures will be achieved through the proposed design, construction methods and monitoring detailed in Section 5 of this DWP and elsewhere. Should monitoring indicate that additional building specific protection is required, the form of protection will be confirmed by the Project Built Heritage Specialist on a case by case basis.

14th April 2016

Cooper and Company

Section 11.1.9 says that AT will consult with HNZ in the preparation of a signage protocol for the CPO. Cooper and Company would also like to be involved in the signage protocol

Text updated to state that AT will consult with HNZPT and the CPO long-term lessee, Cooper and Company, in the preparation of signage protocol for the CPO.

14th April 2016

Cooper and Company

Section 12 notes that any material changes to the DWP will require approval from Council. However it should also note that any material changes also need to be notified to the CLG under condition 8.7

Section 12 updated with new sub-sections on the review and updating process, including CLG notification

10th May 2016

Cooper and Company

Table 9.1 contact details - Bruce Petry is listed twice.

Table 9.1 updated to remove duplication.

10th May 2016

Cooper and Company

Section 10 should be updated to specifically reference consultation with Cooper and Company regarding the CPO.

Section 10 text updated to reference the requirement to consult with Cooper and Company in relation to the management of the CPO heritage fixtures.

Independent Peer Review Comments

•

An Independent Peer Review of the draft Built Heritage Section of the Historic Heritage DWP was undertaken by Jeremy Salmond, from Salmond Reed Architects, with peer review comments received on 29th February 2016. The comments received are as follows: Condition

Section of DWP

Comment

Response

BTC Designation Conditions 8

8

29.1

Whole document

See notes below

Document updated as per comments below

29.2(a)

Section 2

Appendix C sets out a partial list of specific heritage features of the CPO. It is not clear whether this is a summary of the conservation plan assessments or a new assessment – and if new, there is no explanation of the relationship between these assessments and those of the Conservation Plan. It is not clear whether this represents only values relevant to the proposed works.

There is no explanation of the practical implication of these assessments, or how they bear on the implementation of the works.

This would have greater utility if it was approached as a review of the earlier assessments, updated to reflect more recent change.

Additional text added to Appendix C to state that it provides a summary of specific heritage features of the CPO building as outlined in the Revised CPO Conservation Plan (2003).

The information in Appendix C serves to identify the heritage features and values of the CPO as per the Conservation Plan as required by the designation conditions and informs the management of heritage features and values during construction of the Project that is outlined in the DWP

29.2(b) and (c)

Section 3

The chosen design option is understood to reflect the optimum construction method. On that basis, this may be presumed to have the least physical impact on the heritage building, and therefore the least adverse effects on heritage values.

It is noted that “from a heritage perspective, this preferred solution will only affect the fabric, features and areas of the CPO impacted through the redevelopment and conversion of the building into the current Britomart Transport Centre in 2002-2003.”

The lack of a specific method statement for salvage and reuse of the original timber floor of the main concourse (now to be lowered) makes it difficult to fully comprehend the impact on this heritage fabric.

Reference to the impact on the heritage fabric of the timber floor in the Banking Chamber is not relevant to this section of the DWP, which is an assessment of alternative construction methods from AT’s original reference design. The timber floor in the banking chamber was to be reinstated in a lower position under the reference design.

29.2(d)

Section 4

Section 4 states that “little salvaged works are expected”. It is noted that “The key focus for the methodology and

Additional text included in paragraph 1 of Section 4

BTC Conditions dated 27 May 2015

Condition

Section of DWP

Comment

Response

salvage strategy will be the extent of floor removal within the CPO, and the ability to reuse materials from the raised central timber floor.”

It is not possible to assess the impact of this at this stage, and to that extent, the consent condition has yet to be satisfied.

Note that “A comprehensive set of measured drawings (foundation, floor and roof plans, elevations and sections) will incorporate all relevant elements that contribute to an understanding of the CPO, construction, development and use of the structure.”

Not clear if this is simply for the purpose of recording the building as it stands, or if this will be used to record impact of the contract works on heritage fabric.

29.2(e)

Section 5

The Project works have the potential to result in damage to the built heritage values of the CPO or adjacent heritage buildings. Section 5 outlines the proposed methods for monitoring building damage. Key monitoring activity relates to structural movement.

This appears to satisfy the intent of this condition.

No change required to DWP

29.2(f)

Section 6

While the methods for recording physical impact are clear, it is not entirely apparent how effects on “heritage vales” will be monitored during the works or recorded after the event. Suggest this may require reevaluation of heritage values at the conclusion of the works, in a format similar to Appendix C.

Providing works within the CPO building are undertaken in accordance with this DWP, it is not expected that heritage values will be negatively affected as a result of the construction works. -Re-assessment of the CPO’s heritage values will occur in the form of a revised conservation plan. No change required to the DWP.

29.2(f)(i)

Section 6

Not clear whether the “adaptive reuse” is intended to relate to new functional uses for the building, or parts of the building, or the reuse of building fabric salvaged during the works (reusing salvaged materials is not technically “adaptive reuse”).

This specific level of detail is not considered relevant to the DWP. No change required.

29.2(f)(ii)

Section 6

There is nothing to show what, if any, material will be retained and reused – except, by implication, the floor of the central concourse.

Section 4.2 of this DWP outlines the salvage strategy for the Project.

The provenance of the floor is unclear.

The method of construction presumes that disassembly will result in low amounts of material to be reused and it is unclear where it would be reused in a historically significant manner.

Condition

Section of DWP

Comment

Response There are currently no other elements of heritage significance being disrupted that will have the ability to be reused.

No change required to the DWP

29.2(f)(iii)

Section 6

This section does not address this issue hence it is not possible to assess the effect of this intent.

It will be desirable to ensure that the project heritage advisor is fully part of the design team in order to advocate for the integration of heritage fabric, elements and philosophy into the design process.

Sections 4.2, 7 and 11 of this DWP address protection and reinstatement of key heritage features of the CPO as part of the Project.

It is noted that the Project Heritage Specialist has been part of AT’s design team working on this Project over the duration of the design development.

The design proposed here reflects this inputs. The Project Heritage Specialist will continue to provide specialist heritage inputs through the construction phase.

29.2(f)(iv)

Section 6

This section does not refer to exploring “the adaptive re-use of the Chief Post Office”.

Should be noted that the building has already been adapted for purposes other than those for which it was constructed?

This condition has been deleted in the Conditions as attached to AT’s Confirmation Notice of 17 March 2016 on Notice of Requirement Britomart Transport Centre Designation. No change required to DWP.

29.2(g)

Section 7

These measures are well-described in this section (although the material reads as text book prose rather than proposals specific to this building).

Given the scale and nature of the planned works, it will be pertinent to include methods for managing the potential impact of construction moisture resulting from drilling processes and wet trades such as concrete placement.

Additional text included in Section 7.3 in this regard (last line item in Table)

29.2(h)

Section 8

This section describes a “rectification methodology” agreed with HNZPT and Auckland Council, and it is noted that this forms part of an agreement under the Covenant over the building.

Specific rectification methodologies are to still be agreed in detail.

Additional text included in Section 8 in this regard

29.2(i)

Section 10

Refers to “Sections 8.2.9 and 8.2.10” of the Project Communication and Consultation Plan.

Unable to comment on this, but the basis of engagement with HNZPT and Auckland Council appears to substantially address this condition.

Not clear how public consultation will be implemented.

Communication and Consultation Plan reference to be included once confirmed.

The Communication and Consultation Plan will outline communication with Project stakeholders in relation to built heritage - additional text included in Section 10

Condition

Section of DWP

Comment

Response

29.2(j)

Section 11

Not clear what is intended by the term “the permanent treatment of heritage elements” – but presume this refers to permanent solutions for the conservation and integration of heritage elements affected by the works.

Important to reconcile the statement regarding the preservation of “the spatial identity and quality of the original components of the Banking Chamber” with the lowering of “the floor level of the Banking Chamber”, and whether “clear delineation within the ground floor space” adequately deals with this.

The statement “The design and scale of the retail units on the western wall of the Britomart Station Ground floor (adjacent to the Entrance Vestibule), shall be appropriate to ensure the heritage values of the Banking Chamber Public Space are not reduced” is not particularly meaningful – there is no basis for assessing how new retail spaces will be “appropriate” for this purpose. It will be preferable to include a statement of intent regarding the expectation of high design quality of such new non-heritage features within the ground floor volume.

Not relevant to the DWP – no change to DWP required.

CRL Designation Conditions 41.1

This document

No comment

N/A

41.2

This document

No comment

N/A

41.2(b)

Section 5

Section 5 deals solely with monitoring of movement in buildings adjacent to the works and while not specifically related to built heritage buildings or structures, is equally applicable to these. Heritage buildings subject to monitoring are identified in other parts of the DWP (it is noted that Condition 29 relates specifically to the former Chief Post Office).

As a methodology, the proposals outlined appear to fully satisfy the intent of this condition.

No change to DWP required

41.2(e)

•

N/A

Methods for the protection of the former Chief Post Office are outlined in Section 7 and are discussed in relation to Condition 29 above.

Refer above Section 7 and Condition 29 above – no change to DWP required

41.2(f)

Section 7 describes a “rectification methodology” agreed with HNZPT and Auckland Council, and it is noted that this forms part of an agreement under the Covenant over the building. Specific rectification methodologies are to still be agreed in detail.

No change to DWP required

41.2(g)

The basis of engagement with HNZPT and Auckland Council outlined in Section 10 appears to substantially address this condition.

It is not clear how public consultation will be implemented.

The Communication and Consultation Plan will outline communication with Project stakeholders in relation to built heritage as outlined in Section 10 of this DWP – no change to DWP required

A further Independent Peer Review of the draft Built Heritage Section of the Historic Heritage DWP was undertaken by Jeremy Salmond to review the amendments made to this section of the DWP as a result of Auckland Transport’s confirmation of the altered BTC designation conditions. A second round of peer review comments was received on 18th May 2016. The comments received are as follows: Condition

Section of DWP

Comment

Response

29.2(f)(ii)

Section 6

I disagree that "the provenance of the (timber) floor is unclear". This was well documented during the adaptation of the CPO building, and reused timbers salvaged from the original public chamber of the CPO. These were (and are) regarded as having clear heritage significance.

The CRL Project team has been in discussion with HNZPT and Auckland Council for over two years regarding the provenance and heritage significance of the current raised timber floor. The Project team has undertaken an extensive process of research to establish, beyond doubt, that the current mixture of Kauri and Jarrah timber is part of the flooring from the CPO Banking Chamber, as it existed, prior to the 2002/03 works starting. The investigation concluded that the Kauri timber is reused but that the Jarrah appears new. The research involved review of the construction drawing set, Salmond Reed, HNZPT, Auckland Council and JASMAX Archives, and included discussions with key construction project personnel. After inspection of the flooring, it was decided there is little likelihood of substantial salvage, because the fixing of the floor is such that it will be very difficult to remove, as it is both ‘secrete nailed’ through the tongues of the floor boards, and glued directly to sheet ply.

Therefore, it has been assumed that the material is of little or no heritage value. Given the above research, the provenance of the raised timber flooring within the former CPO Banking Chamber remains uncertain and therefore no amendments to the DWP have been made.

•

29.2(f)(iii)

Section 6

While it has always been assumed that the Project Heritage Specialist has been part of AT's design team at all stages, and will continue to be so, the comment was made in the absence of a clear statement to that effect. The assurance is however accepted and endorsed as appropriate and fundamental to effectively satisfying condition 29.

No change to the DWP required.

29.2(f)(iv)

Section 6

The deletion of this condition is acknowledged

No change to the DWP required.

29.2(j)

Section 11

If these matters are “Not relevant to the DWP”, suggest that those reference are deleted from the DWP.

References discussed in Section 11 are considered necessary to outline the proposed reinstatement works of heritage elements. No amendments to the DWP made.

The preparation of this DWP was undertaken in consultation with Bryan Bennett, Principal Specialist Built Heritage Implementation from Auckland Council Built Heritage Unit. Bryan Bennett comments on the DWP are as follows: Condition

Section of DWP

Comment

Response

What method will be used to protect and separate the granite bases beneath the lamp-standards on the front elevation of the CPO building ?

The granite bases will be left in place and protect wrapped with sheets of ply and strapped. The diaphragm wall and underpinning works will be constructed to support these plinths during the CRL tunnel works.

A full methodology review of this will be carried out before the works start with a full risk assessment and liaison with the Built Heritage Specialist Bruce Petry, Reverb, to ensure full protection. If required as further protection, steel sheets may also be used.”

BTC Designation Conditions 29.2 (d)

Section 4.2.1

•

•

The preparation of this DWP was undertaken in consultation with Myfanwy Eaves, Senior Specialist: Archaeology from Auckland Council Heritage Unit. Myfanwy Eaves comments on the DWP are as follows: Condition

Section of DWP

Comment

Response

29.2(d)

Section 4.1.4, Table 4.2

Please be aware that the “Other Techniques” will also occur as a requirement of archaeology conditions and HNZ archaeology authority (potentially). Raising this are the separate statutory requirements to record excavations in this area may lead to H&S concerns for the contractor – better to acknowledge multiple requirements for the recording of excavation now (for HNZ, Council CHI and Council BHI/Reverb).

This DWP is in response to the BTC and CRL designation conditions requirements to photograph various heritage aspects of the CPO. Suggested amendment is outside the scope of the CRL and BTC conditions, therefore no change to the DWP required.

A copy of the Built Heritage Section of the Historic Heritage DWP was also provided to HNZPT on 4 May 2016 for their review and comment. As at the time of submitting the DWP to Auckland Council as part of the Outline Plan for the CRL Contract 1 works, comments were yet to be received from HNZPT.

Appendix I: •

Register of Plan Updates

Annual Review

Updates

Date

Updates have been made to the following sections: • Section 1.1 – addition of information about the reviewer of the DWP. • Section 3.1 - update to construction method to include details of additional works that weren’t covered in the original DWP relating to underpinning, and demolition works in the basement area under the entrance lobby.

• Section 3.2.1.2 – deleted Figure 3.1, refer to full updated drawing in Appendix.

• Section 4.3 – detail added about the timber floor and entrance stairs and the salvage strategy for both • Section 4.4 – new section outlining column recording required prior to any demolition works.

• Section 4.5 – new section inserted on building record and salvage strategy report • Section 5.1 – corrected Section reference in report • Section 7.1 – updated since protection measures have now been confirmed, and copy of the report outlining this is provided as a new appendix F. • Table 7.2 – updated table to include protection measures which have been agreed with Project built heritage specialist.

• Section 7.3 – deleted sentence since protection measures have been confirmed as per Section 7.1 comment.

• Section 7.6.3 – updated to focus on potential issues around water ingress to surrounding buildings.

• Table 9.1 – Updated contact details.

• Section 10 – Updated to reflect agreed process with Built Heritage Specialist for consultation with HNZPT and Auckland Council, and how we will receive evidence of this consultation. Removed reference to Communication and Consultation Register, as there are no specific details in this plan about required consultation in relation to heritage.

• Section 11 – new section summarising the project-specific documents that are required to support the processes described in this plan.

• Appendix F – new appendix providing the building record and salvage strategy report.

• Appendix F – new appendix summarising the key updates to the DWP during each annual review.

October 2017

Updates have been made to the following sections: • Section 4.3.1 Update to stair removal process, extent and storage location following completion of these works.

• Table 7.2 Update to protection of tiled walls, free standing columns, and basement area under the lobby.

• Various updates to change reference from Auckland transport to CRLL where appropriate.

• Section 13 Amendments to correct documents supporting the processes described in this plan.

July 2018