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  • LUSH FIRE & PLANNING 3 Paterson Road

    Pinjarra WA 6208 ABN 74 232 678 543

    Bushfire Attack Level (BAL) Assessment Report Exbury Lane Wentworth West

    Report Details

    Job No Report Version Assessment Date Report Date

    19-031 A 20 May 2019 24 May 2019

    Property Details

    Street No Lot No’s Plan Street Name

    10, 14, 24 &

    26

    92, 94, 99 & 100

    411219 Exbury Lane

    Locality Success State WA Postcode 6164

    Local Government Area Cockburn

    Description of the building or works

    Residential Lots

    Accredited Practitioner Details

    Name Bushfire Planning and Design (BPAD) Accreditation Number

    G Lush Level 2 Bushfire Planning Practitioner BPAD27682

    Name Geoffrey Lush

    Authorised Practitioner Stamp

    Company Details 3 Paterson Rd Pinjarra WA 6208 0418954873 geoffrey@lushfire.com.au

    Reliance on the assessment and determination of the Bushfire Attack Level contained in this report should not extend beyond a period of 12 months from the date of issue of the report. If this report was issued more than 12 months ago, it is recommended that the validity of the determination be confirmed with the Accredited Practitioner and where required an updated report issued.

  • Exbury Lane Wentworth West

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    Background

    This report is prepared for Richard Noble & Company to support the development of Lots 92, 94, 99 and 100 Exbury Lane, Wentworth West Estate Success. The property details are as follows:

    No Lot Plan Volume Folio Registered Proprietor Area (m2)

    10 92 411219 2924 152 Gold Estates Holdings Pty Ltd 224

    14 94 411219 2924 154 Gold Estates Holdings Pty Ltd 224

    24 99 411219 2924 159 Gold Estates Holdings Pty Ltd 209

    26 100 411219 2924 160 Gold Estates Holdings Pty Ltd 204

    All of the subject land is defined as being bushfire prone and this triggers the application of Australian Standard AS3959 Construction of Buildings in Bushfire Prone Areas under the Building Code of Australia. A building permit application for any new dwelling in a bushfire prone area requires that a Bushfire Attack Level (BAL) Assessment be undertaken to determine the relevant construction requirements under AS3959 Construction of Buildings in Bushfire Prone Areas. It is noted that the Estate is subject to:

    ➢ A previous Bushfire Management Plan (BMP) was prepared in June 2015 by TME Town Planning Management Engineering Pty Ltd (Ref 12072) to support the subdivision application; and

    ➢ An approved Local Development Plan - Wentworth West Stage 3.

    The subject land has an R40 Residential Density Coding. The Local Development Plan requires:

    • Outdoor living areas are encouraged in the setback area adjacent to the POS for lots 88 - 101; and

    • Dwellings on lots 88 - 101 must be orientated to address the POS with major openings from a habitable room.

    The rear boundary setback is to be determined in accordance with Table 2b: Boundary setbacks - Walls with major openings of the Residential Design Codes (R-Codes). For a wall height of 3.5m or less and a wall length of 9m or less the setback requirement is 1.5m. For the purpose of this BAL Assessment the 1.5m setback has been used to define the development area within the lots.

    Explanatory Notes

    The Bushfire Attack Level (BAL) Assessment measures the severity of a buildings potential exposure ember attack, radiant heat and direct flame contact in a bushfire event. Each BAL rating corresponds to different construction requirements and provisions. The Bushfire Attack Level (BAL) Assessment measures the severity of a buildings potential exposure ember attack, radiant heat and direct flame contact in a bushfire event. The BAL rating is determined through the identification and assessment of the following parameters:

    • Fire Danger Index (FDI) rating; assumed to be FDI – 80 for Western Australia;

    • All classified vegetation within 150m of the subject building;

    • Separation distance between the building and the classified vegetation source/s; and

    • Slope of the land under the classified vegetation. AS3959:2018 has six (6) levels of BAL, based on the radiant heat flux exposure to the building, and also identifies the relevant sections for building construction as detailed in Table 1.

  • Exbury Lane Wentworth West

    3

    Table 1 BAL Ratings

    Bushfire Attack

    Level (BAL)

    Classified vegetation within 100m of the site and heat flux exposure

    thresholds

    Description of predicted bushfire attack and levels of exposure

    BAL-LOW See clause 2.2.3.2 There is insufficient risk to warrant any specific construction requirements.

    BAL-12.5 ≤ 12.5kW/m2 Ember attack

    BAL-19 > 12.5kW/m2 to ≤ 19kW/m2 Increasing levels of ember attack and burning debris ignited by wind borne embers together with increasing heat flux.

    BAL-29 > 19kW/m2 to ≤ 29kW/m2 Increasing levels of ember attack and burning debris ignited by wind borne embers together with increasing heat flux.

    BAL-40 > 29kW/m2 to ≤ 40kW/m2 Increasing levels of ember attack and burning debris ignited by wind borne embers together with increasing heat flux with the increased likelihood of exposure to flames.

    BAL-FZ > 40kW/m2 Direct exposure to flames from fire front in addition to heat flux and ember attack.

    The applicable BAL construction measures do not guarantee that a building will survive a bushfire event on every occasion. This is substantially due to the degree of vegetation management, the unpredictable nature and behaviour of fire and extreme weather conditions.

    Site Assessment

    The assessment of this site / development was undertaken on 20 May 2019 by a BPAD Accredited Practitioner for the purpose of determining the Bushfire Attack Level in accordance with AS 3959 - 2018 Simplified Procedure (Method 1). All vegetation within 150m of the site / proposed development was classified in accordance with:

    • Clause 2.2.3 of Australian Standard AS3959 Construction of Buildings in Bushfire Prone Areas;

    • The Visual Guide for Bushfire Risk Assessment in Western Australia; and

    • Applicable Fire Protection Australia BPAD Practice Notes.

  • Exbury Lane Wentworth West

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    Site Assessment

  • Exbury Lane Wentworth West

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  • Exbury Lane Wentworth West

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    Photograph Locations

  • Exbury Lane Wentworth West

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    Photo No 1 Plot No 1

    Vegetation Classification

    Class A Forest - Low open forest A-

    04

    Description

    Melaleuca vegetation to 10m height in the swamp area. It is technically closed as the foliage coverage is 90% but this does not comply with Class 18. Very heavy fuel loads. Vegetation is situated on the northern and north eastern side of the fire service access route.

    Photo No 2 Plot No 1

    Vegetation Classification

    Class A Forest - Low open forest A-

    04

    Description

    Melaleuca vegetation to 10m height in the swamp area. It is technically closed as the foliage coverage is 90% but this does not comply with Class 18. Very heavy fuel loads. Vegetation is situated on the northern and north eastern side of the fire service access route.

    Photo No 3 Plot No 2

    Vegetation Classification

    Class B Woodland - Low woodland

    B-07

    Description

    Banksia woodland to 5m with mixed understorey and foliage cover of less than 30%. Moderate to heavy fuel loads. Mixed scrub understorey, overall woodland classification as height exceeds 4m and is expected to increase over time.

    Photo size 9cm width

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    Photo No 4 Plot No 2

    Vegetation Classification

    Class B Woodland - Low woodland

    B-07

    Description

    Banksia woodland to 5m with mixed understorey and foliage cover of less than 30%. Moderate to heavy fuel loads. Mixed scrub understorey, overall woodland classification as height exceeds 4m and is expected to increase over time.

    Photo No 5 Plot No 3

    Vegetation Classification

    Class C Shrubland - Low shrubland

    C-12

    Description

    Revegetation between the fire service access route and POS area. Consists of grass trees with other ground covers. Moderate to heavy fuel loads.

    Photo No 6 Plot No 3

    Vegetation Classification

    Class C Shrubland - Low shrubland

    C-12

    Description

    Revegetation between the fire service access route and POS area. Consists of grass trees with other ground covers. Moderate to heavy fuel loads.

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    Photo No 7 Plot No 3

    Vegetation Classification

    Class C Shrubland - Low shrubland

    C-12

    Description

    Revegetation between the fire service access route and POS area. Consists of grass trees with other ground covers. Moderate to heavy fuel loads.

    Photo No 8 Plot No 4

    Vegetation Classification

    Class D Scrub - Closed scrub D-13

    Description

    Vegetation between the f

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