item 9.1 · hand drawn sketches and photo record of observations. ... which is typical additional...

IB

ORDINARY MEETING OF COUNCIL

3 December 2013

TABLED ITEM

ITEM 9.1.7

WGE - vital experience Albany Brisbane Busselton Darwin Gold Coast Melbourne Perth Shenzhen Sydney

26 Brookman Street, Perth Structural Inspection Report

Ms. Judith Pugh 31 October 2012

Revision No. 0

Prepared by Gary Sollitt Project Number: 24371-PER-S-54 Ground Floor, 226 Adelaide Terrace, Perth WA 6000

Phone (08) 6222 7000 Fax (08) 6222 7100 Email [email protected] Web www.wge.com.au

2 6 B R O O K M A N S T R E E T , P E R T H S T R U C T U R A L I N S P E C T I O N R E P O R T

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REVISION

Revision

REVISION DATE COMMENT APPROVED BY

0 19/10/2012 DRAFT GRS

1 31/10/2012 FINAL GRS


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CONTENTS i

Contents

1. INTRODUCTION ........................................................................................................................................................... 1

BACKGROUND SUMMARY .......................................................................................................................................................................1 1.1 SCOPE OF WORKS....................................................................................................................................................................................1 1.2 METHODOLOGY ........................................................................................................................................................................................1 1.3 CONSTRAINTS ...........................................................................................................................................................................................2 1.4 SAFETY IN DESIGN ...................................................................................................................................................................................2 1.5 USE OF REPORT .......................................................................................................................................................................................2 1.6

2. OBSERVATIONS .......................................................................................................................................................... 3

GENERAL COMMENTS .............................................................................................................................................................................3 2.1 WEST FACING ELEVATION (FRONT ELEVATION) .................................................................................................................................3 2.2 SOUTH FACING ELEVATION ....................................................................................................................................................................4 2.3 INTERNAL ...................................................................................................................................................................................................4 2.4

3. CONCLUSION .............................................................................................................................................................. 6

APPENDIX 1 – PLANS

APPENDIX 2 – INSPECTION PHOTOGRAPHS


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INTRODUCTION 1

1. Introduction This report has been prepared for the current owner of the property Ms Judith Pugh The report has been partly funded by the current owner of the property and the City of Vincent. The purpose of the report is to address the specific brief developed by the City of Vincent which the key objectives are stated below in section 1.2 of this report The areas inspected included the roof structure, load bearing walls and columns, suspended floor structures and ground bearing floor structure. The defects noted were evident at the time of our inspection. The structure was visually inspected by Gary Sollitt (Structural) on Thursday 4th October 2012

Background Summary 1.1

The property is located at No. 26 Brookman Street is included in the Brookman & Moir Streets Precinct. It is the precinct that is listed on the State Register and the City of Vincent's Municipal Inventory. We understand Airey Taylor consulting has previously been commissioned to prepare a Structural Condition Report in 2008 to address the structural degradation of the property. A new Structural Engineers Report has been requested to develop an appropriate structural remediation and proposed methodology to the property. It is envisaged that the recommendation and options proposed will provide the basis for the owners to engage a suitable qualified architect to prepare plans for the restoration and reconstruction of the property that recognised the heritage values of the property.

Scope of Works 1.2

The structural engineer is to provide a report, which includes the following key components: A detailed outline and accompanying rationale of the elements of the building which can be practically retained conserved and

restored; A detailed outline and accompanying rationale of the elements of the building which would require reconstruction; An appropriate methodology to undertake structural and/or non-structural remediation to the property that is cognisant of the

cultural significance of the property, whilst also addressing the structural condition and integrity of the building; A list of options and recommendations to assist a suitable qualified architect to prepare plans for a Planning Application to be

submitted to the City of Vincent for the property; and

Methodology 1.3

Attend site at 26 Bookman Street, Perth, Review any previous documentation relating to the building including drawings and reports if available, which includes previous

engineered report and conservation reports if available, to be issued by others. Liaise with the appointed builder to discuss current condition and intent for the development. Inspect all significant and accessible portions of the structure and services on site, both externally and internally. Hand drawn sketches and photo record of observations. Comment on any observed defects; identify items for rectification or remediation. The report shall advise on structural viability in regard to preservation and safety of current building condition to both the

historical and modern structures. This conclusion shall focus purely from the structural point of view based on site observations and visual observations.

Provide draft report: The report will record the findings from our inspection and recommended actions, containing relevant digital photographs, for comment prior to completing two copies of the final report for the Clients consideration.

Structural reports do not provide budget estimates. Structural to provide table of works including item, defects description and quantity so that the client can get these items costed by a QS.


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INTRODUCTION 2

Constraints 1.4

We note that many areas of the building cannot be visually examined and that the building as constructed frequently differs from design documentation. As such, it is probable that our inspection cannot identify all of the potential defects or shortcomings of the structural services. It is our goal to maximise the extent of our investigation within the constraints of time and the level of investigation defined in this letter. No testing of material samples have been carried out. Similarly, comments on specialist services not included in our areas of expertise have been excluded. This includes but not limited to asbestos and acoustics. No Geotechnical or sub-surface investigations were carried out. The capacity of the engineering services will not be checked by calculation. However, readily apparent inadequacies will be discussed in the report with recommendations for resolution. The report will specifically exclude the following aspects: Environmental considerations. Hazardous substances. Acoustics. BCA compliance issues outside of the services inspected including fire compartmentalisation, fire doors and fire shutters. The client should consider the need to engage specialist consultants to report on the above areas.

Safety in Design 1.5

As this project involves no design or site supervision by WGE we advise that we will not prepare a Safety in Design report for this project.

Use of Report 1.6

The final report may be used by the Client as a record of our opinion of the condition of the engineering services at the time of the inspection by Wood & Grieve Engineers. The report may be considered valid for a period of three months from the date of the report. The use of the report by third parties is not permitted.

Available Documents 1.7

Airey Taylor Dilapidation Report for the property which is undated but was undertaken on 7th October 2010 for 24 and 28 Bookman Street.

Airey Taylor Structural Assessment report which undated but was undertaken on 17 September 208 by My PG Airey. Heritage Assessment of the property Ref PLAN0128 / PLAN0098 The design intent for the property Historic street plan for the historical precinct. City of Vincent Briefing document for 26 Brookman Street Perth.


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OBSERVATIONS 3

2. Observations

General Comments 2.1

WGE attended 26 Bookman Road Northbridge on Thursday 4th October. The structural inspection was carried out by Gary Sollitt of Wood and Grieve Engineers. The inspection was carried out with the current owner of the property, Ms Judith Pugh and partly with a builder appointed by the owner for the proposed works. The brief for the inspection has been issued by the City of Vincent in conjunction with the Heritage Council, as stated in Section 1.2 of this report The property is located in a Heritage Listed Precinct which has significant historical value to the local and state heritage for the area. In the area of Brookman Street a number of properties have undergone authentic and sympathetic reinstatements to the original intent for the buildings. Observations along Brookman Street of this reinstatement is varied in success, with some properties achieving a very high standard for the reconstruction of the property which reflects the original precinct to some poor interpretations to the original intent. This particular property has had significant internal alterations as well as very little external maintenance to façades. The geology in the area which is historically very soft ground, the property was noted to have suffered from suspected differential settlement.

West Facing Elevation (Front elevation) 2.2

The front of the property has significant diagonal and horizontal cracking noted around the main entrance doorway and the adjacent bedroom window. The cracks generally follow the mortar bed lines and were noted to be 7-10mm in width. The cracking in this area was noted internally in the bedroom. This portion of the front wall was noted to have bowed outwards externally by some 30-50mm. This bow is located directly behind the current service box for electric into the property. The property is semi-detached by a party wall located on the north boundary. A masonry blade wall is visible from the front veranda which was noted to have deteriorated and rotated away from the building. Cracking was noted in the mortar beds and the in filled arch. The cracks were noted to be in excess of 20mm. The wall was visibly twisted as well as rotated away from vertical. Above the bedroom window externally a steel strap was noted, which is typical additional lintel support for this type and age of property. The lintel was noted to have deteriorated with visible rust. The strap was also noted to have become dislodged which relates to the bow of the front elevation of the wall. The front veranda slab of the property was noted to have significantly rotated away from the building and sunk; this in turn had exposed the shallow limestone footings which were visibly noted to be in a poor condition. The exposure of the footings will allow water ingress into the reactive soil supporting the foundations, this in turn will cause the sol to swell and cause localised subsidence to the building. The front elevation was visually inspected and noted to have the main bedroom window have been replaced with aluminium framing which is a non-representative window for the original construction. Cracking was noted horizontally directly above the window some 6 brick courses above. This crack was noted to be 7-10mm in width and would appear to be located in a mortar bed. Vertical cracking was noted directly below the window from the underside of the window sill to the top of the foundations. This crack is suspected to continue to the base of the foundations but could not be inspected fully at the time of inspection. The front concrete path was noted to again rotate away from the building with significant settlement which has exposed the shallow foundations. The exposure of the footings will allow water ingress into the reactive soil supporting the foundations, this in turn will cause the sol to swell and cause localised subsidence to the building. The timber works forming the facia and soffit for the property were noted to be in a poor condition with paint peeling and surface decay noted to the majority of the timber. These elements are believed not to be original.


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OBSERVATIONS 4

The concrete window sills were noted to have cracked and split to both the front windows. The cracks were noted to be some 10mm in width and have rotated away from the building. The front entrance to the property has significant cracking noted around the opening with the concrete door lintel rotated away from vertical and to one side of the opening. Cracking was noted all around the door frame in a random paten. Window frame to both front windows has detonated with some localised rot noted. Gaps all-around the window sill were noted which will allow water ingress into the cavity. This will expedite the deterioration of the inner fabric of the property.

South Facing Elevation 2.3

The south facing façade was noted to have been rendered. The cementitious render was noted to vary from 5-15mm in thickness. The render appears very brittle and stiff for the wall behind. Some local areas of brick work and render have been historical repaired. Diagonal cracking was noted from the front corner of the building to the mid length of the property at roof level. The crack was noted to be approximately 45 degrees. This crack is also reflected internally within the building. The wall was noted visibly bowed outwards with additional diagonal, vertical and horizontal cracking radiating from the most pronounced bow in the wall. The cementitious render was noted to be thinner in this location which leads to the conclusion the bow is historic, and has been masked by the render. Along the south facing elevation cracking was noted around the windows and penetrations through the wall the wall was noted to be damp as the wall is not exposed to direct sunlight due to the close proximity of the adjacent property and orientation. All windows on the south facing elevation have been replaced with aluminium framing which is a non-representative window for the original construction. The access path was noted to have rotated away from the building exposing the shallow foundations. Localised areas of fretting masonry were noted along this elevation and in some areas mortar was noted to be missing. This local area the masonry could be removed by hand and found the masonry was very damp. Towards the rear of the dwelling the property has been extended by the current owners, which does not reflect the original building design or heritage. The property had been recently reroofed with a corrugated tin replacement roof as well as the gutters, fascia, downpipe, bargeboards and soffits have been replaced The two chimney stacks were visually inspected from the ground and were noted to be in a fair to good condition. Concern is expressed on the flashing around the chimney stacks. Reportedly water ingress into the property around the chimney stacks has occurred historically. The steel straps noted to support the arched brick lintels were noted to be in a poor condition.

Internal 2.4

The main floor within the property, which would have originally been a suspended timber floor, was noted to have been replaced historically as a concrete ground bearing slab. The floor finish to the majority of the property was tiled. The floor undulates along the entrance hall and across the front of the property. The undulation is noted to be some 50mm across the property. The front bedroom was noted to have cracking around the front elevation windows which are replicated around the external wall and entrance door. These cracks were noted to be 5-7mm in width. The ceiling was noted to have historical water staining to the majority of the exposed finish. The chimney breast in the bedroom was noted to have corresponding cracking identified externally within the room. The internal cracks have been historically repaired but have reappeared. The chimney breast had cracking around the masonry with significant historical water ingress staining on the ceiling. The floor undulates from the entrance from the hall downwards towards the external wall on the south elevation. The majority of the internal walls have been historically replaced or removed by previous owners. Which also include the historical removal/replacement of all internal ceilings, skirting boards, door jambs and architraves.


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OBSERVATIONS 5

The further you explore the property the historical significance and value of the buildings diminished substantially. The structural alterations and extensions to the property have been constructed using modern materials built to a fair standard. The level of cracking and detonation also diminishing the further away from the front elevation you explore. At the rear a crack was noted between the adjoining property in the party wall. The crack was noted to be in excess of 30mm in width and runs the full height of the wall. The shared chimney breast which is located in the main living room is not utilised by the current occupier, however when the adjacent property owner uses the fire this property is filled with smoke from the adjacent fire. This is reported caused by the inadequate fire wall or separation between the properties.


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CONCLUSION 6

3. Conclusion The originality and uniqueness of this property has been compromised by historical alterations and adaptions of the property. Generally the building has had little maintenance over the years, with some poor repairs carried out. The property has been altered significantly internally as well as extended which is not reflected in the precinct intent. From inspecting the street scene along Bookman’s Road, this property is a poor example of the type of property in this area. The property has been significantly changed, altered over time and has very little significant historical value compared to other property in the area. We believe to repair and renovate the front facade of this property is uneconomic and impractical as the condition of significant elements of the front facade have deteriorated and are beyond economic repair. The render and paint on the façades is suspected to have been applied to cover up significant movement of the property which has had very little if any maintenance over the years. Some local areas of the masonry can be classed as dangerous and the owner needs to take some action to protect the property during this interim period until a decision is given by the local shire. Some areas and details of the building can be deconstructed and reused in the proposed development but these only relate to the chimney stacks, key detail to the timber facia and eaves details noted The property visually has been altered historically significantly with the replacement of all the windows aluminium framing which is a non-representative window for the original construction, the painting of the front elevation and cementitious render opted on the front and south facing elevation. Also the majority of the internal walls have been historically replaced or removed by previous owners. Which also include the historical removal/replacement of all internal ceilings, skirting boards, door jambs and architraves Due to the extensive alterations to the internal layout the inner space of the property has little Heritage significance left intact. The façade of the building is the only original element to this building which reflects the original character of the property but this is in poor condition with the historical facade treatments which are not compatible with the original construction and will cause significant damage in removal. With the area being a Heritage Precinct with some fully restored houses to the original façades the street scene in the area is generally a high quality, however this particular property is a poor example of the type of property and construction used in the area. After review of the Peter Airey reports we conclude the recommendations put forward in these reports are fair and reasonable based on our visual observations and knowledge of the historical soil conditions of the area. The area historically has suffered from issues with differential settlement. The original brief directed the inspection in the following way: A detailed outline and accompanying rationale of the elements of the building which can be practically retained

conserved and restored; - From the visual observation from site the current condition of the structural form of the property, the historical

adaptations as well as the related condition of the heritage significance of the property there is little of the original building that can be practically retained, conserved or restored.

- The front elevation brick work will be significantly damaged and compromised with any removal of the facade treatment

to expose the original masonry to the already distressed walls. - The internal layout has been significantly compromised and altered over a number of years which has devalued the

heritage Keep these alterations are constructed poorly using modern building materials. - The roof has been re clad which again has used modem day corrugated sheeting which again is not original and has

devalued the Heritage significance of the property. - The areas that can be reused are focused on small features and elements of the property such as the chimney capping

which from the visual inspection is in good condition.


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CONCLUSION 7

- The timber feature eaves details are suspected not to be original but with some restoration can be reused in the property.

- As well as the alteration and compromise to the internal layout, the historical removal of all internal architectural and

decorative mouldings, architraves, skirting boards and flooring should be noted as there is nothing authentic of this sort that can be retained, conserved or restored

A detailed outline and accompanying rationale of the elements of the building which would require reconstruction; - From our observation and the current condition of the property the entire front facade would need to be reconstructed

as well as a portion of the south facing external elevation. The remainder of the internal fabric of the building holds little heritage value and is not currently reflective of the original property.

- The removal of the façades for reconstruction will affect the remainder of the property and will seriously affect the

structural integrity of the building fabric as well as the adjoining property. An appropriate methodology to undertake structural and/or non-structural remediation to the property that is

cognisant of the cultural significance of the property, whilst also addressing the structural condition and integrity of the building;

- As stated in the first point the property itself has a low cultural and heritage significance in the current condition. The

damage and settlement observed in the building cannot be practically repaired without compromising the structural integrity of the majority of the building and being disproportionate in cost to the value of the property.

A list of options and recommendations to assist a suitable qualified architect to prepare plans for a Planning

Application to be submitted to the City of Vincent for the property; and - We would recommend a suitable heritage experienced Architect is engaged to either document the facade to replicate

and reinstate the original intent of the building or is employed as a consultant with a watching brief to assist and direct the owners into achieving the replica building.

- Alternatively if agreed between all parties that there is sufficient documentation of the facades in the precinct available

then a heritage experienced architect may not be essential instead a proven heritage experienced builder could be employed, pending review of experience of this type or work.

- The Heritage Council can also assist in this process. We believe the City of Vincent has documentation to assist any

owner in the area to reconstruct the original intent of these important dwellings with detailed documentation highlighting the set out of the key features of the front facades.


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APPENDIX 1 – PLANS

Appendix 1 – Plans


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Appendix 2 – Inspection Photographs


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1 – Horizontal cracking noted above the main front bedroom window (West elevation)

2 – Vertical cracking noted with horizontal settlement to the front façade (West elevation)


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3 – Timber soffit and eaves are in a poor condition

4 – Significant movement noted in masonry walls to the front façade (West elevation)


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5 – Significant movement noted in masonry walls to the front façade (West elevation)

6 – Lintel visible dislodged from above the doorway


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7 – Significant movement noted in masonry walls to the front façade ( West elevation)

8 – Significant movement noted to party wall( North elevation)


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9 – Significant movement noted to party wall ( North elevation)

10 – Significant diagonal cracking through the wall on the south west corner


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11 – Mortar damage and brick fretting to south elevation

12 – Mortar damage and brick fretting to south elevation


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13 – Poor historical repair to south elevation with new movement noted

14 – Diagonal and horizontal cracking noted to south elevation


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15 – Footing movement and cracking noted around air vent on south elevation

16 – Rear extension with no heritage significance in fair condition


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17 – Cracking noted on south elevation around window and air brick

18 – Vegetation noted on wall which suggests moisture ingress to the building from water discharge from downpipe


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19 – Suspected footing movement and settlement to south elevation

20 – Suspected footing movement and settlement to south elevation


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21 – South elevation visibly bows outwards

22 – South elevation visibly bows outwards


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23 – Chimney in fair to good condition

24 – Damp ingress and diagonal cracking to chimney breast


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25 – Diagonal cracking noted to south elevation, cracking noted internally

26 – Cracking noted to internal wall


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30 – Cracking to internal wall above doorway, suspected no lintel


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31 – Cracking noted to internal south elevation

32 – Significant cracking noted to south wall, crack is noted through party wall (North elevation)


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33 – Significant cracking noted to south wall, crack is noted through party wall (North elevation)

34 – Concrete floor has visible settled.


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35 – Chimney breast in good to fair condition

36 – New roof cladding noted to dwelling boundary