PROVISION FOR FIRE ENGINEERING (FOR DA SUBMISSION)€¦ · Exit Travel Distances - BCA Clause D1.4...

iinnnnoovvaa sseerrvviicceess F i r e S a f e t y E n g i n e e r i n g

B u i l d i n g S e r v i c e s E n g i n e e r i n g

iinnnnoovvaa sseerrvviicceess Pty Ltd

S y d n e y │ B r i s b a n e Phone: 1300 88 22 62 Mobile: 0409 887 929 Post: PO Box K194, Haymarket NSW 1240; PO Box 4788, Forest Lake QLD 4078 Email: [email protected] Web: www.innovaservices.com.au

20 October 2015 Our Ref: 15258-L01a CDArchitects Level 2, 60 Park Street Sydney NSW 2000 Attn: Mr Ziad Chanine RESIDENTIAL DEVELOPMENT – 4 to 6 LOFTUS CRESCENT, HOMEBUSH PROVISION FOR FIRE ENGINEERING (FOR DA SUBMISSION) We refer to the proposed residential development to be located at 4 to 6 Loftus Crescent Homebush, and provide the following in regards to the proposed use of Alternative Solutions to address identified variations to the Deemed to Satisfy (DTS) provisions of the Building Code of Australia 2015 (BCA). The purpose of this document is to assist in the design development process, and to assist the Consent Authority in the determination of the Development Application. PROJECT DESCRIPTION The proposed works include the construction of a new residential development comprising:

Lower Basement - car parking, ancillary Upper Basement - car parking, ancillary Ground Floor - car park entry, entry lobby, residential units Levels 01 to 04 - residential units

The development will comprise the construction of 2 blocks of residential units (Blocks A and B), over basement car parking levels. The site is bounded by Loftus Crescent to the south, a Laneway partly to the north, and adjoining allotments to the east, west, and also partly to the north. Egress from the basement levels is via 2 dedicated exits, which are fire separated from the basement levels and discharge directly onto ground floor. As the basement levels will be fully sprinkler protected, the exit stairs are not required to be constructed as fire-isolated exits. Egress from the ground floor residential units is direct to an open space via the main entry lobbies. For Block A, egress from the above ground residential levels is via a single fire-isolated exit that discharges into the ground floor entry lobby, in lieu of directly to an open space via a fire-isolated passageway. For Block B, egress from the above ground residential levels is via a single fire-isolated exits that discharges into a covered area on ground floor that is not open for at least 1/3 of its perimeter and does not comprise an unobstructed height of at least 3m. Further, travel to the public road exceeds 6m and requires re-entry through Block A. BCA ASSESSMENT DATA The relevant BCA Assessment Data for the proposed development is summarised in Table 1 below. Table 1: Relevant BCA Assessment Data

BCA Reference BCA Assessment

Building Classification and Use Class 2 (residential sole-occupancy units) Class 7a (car parking)

Rise in Storeys 5

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Innova Services Pty Ltd Page | 2 Project No. 15258

Table 1: Cont’d

BCA Reference BCA Assessment

Number of Levels Contained 7

Minimum Type of Construction Required Type A

Effective Height Less than 25m (≈ 13m)

Maximum Size of Fire Compartments To comply for Type A construction

PROPOSED VARIATIONS TO BCA DTS PROVISIONS Outlined below are the proposed variations to the Deemed to Satisfy (DTS) provisions of the Building Code of Australia 2015 (BCA) associated with the subject development. NOTE: At this stage of the design, the identified variations to the DTS provisions of the BCA are not exhaustive, and other variations may arise through the design and development process. Protection of Openings in External Walls - BCA Clauses C3.2 & C3.4

It is proposed to vary the method of protection afforded to a number of openings within the external walls of the building that will be located less than 3m from the side allotment boundaries. The varied protection measures include:

o No protection. o Protection with radiant heat attenuation screens.

It is also proposed to allow the abovementioned openings to remain openable to satisfy the relevant natural ventilation requirements of the BCA.

Exit Travel Distances - BCA Clause D1.4

It is proposed to have an exit travel distance from within the basement levels to a point of choice from which travel in different directions to 2 exits is available of up to 27m, in lieu of 20m.

It is proposed to have an exit travel distance from the entry door into a residential unit on

levels 01 to 04 to a single exit of greater than 6m (worst case being up to 12m).

Travel via Fire-Isolated Exits - BCA Clause D1.7

For Block A, it is proposed to have the fire-isolated exit serving the residential levels of the building discharge into the ground floor entry lobby, in lieu of directly to an open space via a fire-isolated passageway.

For Block B, it is proposed to have the fire-isolated exit serving the residential levels of the

building discharge into a covered area on ground floor that is not open for at least 1/3 of its perimeter and does not comprise an unobstructed height of at least 3m. Further, travel to the public road exceeds 6m and requires re-entry through Block A.

Fire Hydrants - BCA Clause E1.3

It is proposed to have the fire hydrant booster assembly located external to the building, and within 10m of an external wall of the building comprising unprotected openings.

Fire Sprinkler Systems - BCA Specification E1.5

It is proposed to have the sprinkler control valve for the basement levels located within the fire hydrant pump room that is accessed via a fire-isolated exit, in lieu of having direct access from an open space.



Figure 1: Upper Basement Plan (Lower Basement Similar)

Figure 2: Ground Floor Plan

Exit 2 Exit 1

Sprinkler Valve within Hydrant

Pump Room

27m Travel to Point of Choice

27m Travel to Point of Choice

Opening Subject to Assessment

Fire Hydrant Booster Assembly

Fire-Isolated Exit Discharges into Covered Area

Fire-Isolated Exit Discharges into

Entry Lobby



Figure 3: Level 01 Plan




12m Travel to Single Exit











12m Travel to Single Exit 12m Travel to

Single Exit



ACHIEVING COMPLIANCE WITH THE BCA A Building Solution will comply with the BCA if it satisfies the Performance Requirements of the BCA. Clause A0.5 of the BCA states that compliance with the Performance Requirements can only be achieved by:

(a) complying with the Deemed to Satisfy provisions; or (b) formulating an Alternative Solution which -

(i) complies with the Performance Requirements; or (ii) is shown to be at least equivalent to the Deemed to Satisfy provisions; or

(c) a combination of (a) and (b). Clause A0.9 of the BCA states that the following Assessment Methods, or any combination of them, can be used to determine that a Building Solution complies with the Performance Requirements:

(a) Evidence to support that the use of a material, form of construction or design meets a Performance Requirement or a Deemed to Satisfy Provision as described in A2.2.

(b) Verification methods such as - (i) the Verification Methods in the BCA; or (ii) such other Verification Methods as the appropriate authority accepts for

determining compliance with the Performance Requirements. (c) Comparison with the Deemed to Satisfy provisions. (d) Expert judgment

SUMMARY OF PROPOSED FIRE ENGINEERING STRATEGY General

The proposed Fire Engineered Solution will be completed in accordance with the processes described in the International Fire Engineering Guidelines, and will be prepared by a C10 Accredited Fire Safety Engineer (accredited with the NSW Building Professionals Board). Alternative Solution 1 - Protection of Openings in External Walls

Proposed Method of Analysis

A Quantitative Analysis is proposed to be undertaken to assess the Alternative Solution against the relevant Performance Requirements of the BCA, as permitted under Clauses A0.9(b)(i) & (ii) of the BCA. A radiant heat assessment is proposed to be undertaken to determine the amount of heat radiation emitted from the subject openings to the allotment boundaries, which will be compared to the heat flux limits nominated under Verification Method CV1 of the BCA. A radiant heat assessment is also proposed to be undertaken to demonstrate that the subject openings will be able to withstand potential heat flux received, in the event of fire in a building on an adjacent allotment. The potential heat flux received will be based on Verification Method CV1 of the BCA. Proposed Modelling Tools

Program Radiation within the Firewind package is proposed to be used to calculate both the potential radiant heat flux emitted from, and received by, the subject openings. Firewind1 is a collection of fire engineering programs which has grown out of an earlier FIRECALC CSIRO2 and FIREFORM NIST3. Firewind provides the facility for fast calculation of specific fire engineering problems, where the results of these can then be used as part of an overall engineering solution to a particular design situation. 1 Firewind, Computer Software for the Fire Engineering Professional, Version 3.6, 2003 2 Division of Building, Construction & Engineering, Top Ryde, Sydney 3 USA, National Institute of Standards and Technology



Proposed Acceptance Criteria

The Alternative Solution is to be shown to satisfy BCA Performance Requirement CP2 in terms of avoiding the spread of fire between buildings on adjoining allotments. Demonstrating compliance with BCA Performance Requirement CP2 is proposed to be based on Verification Method CV1 of the BCA, which considers both emitted and received radiation.

Emitted Radiation - The emitted radiation from the subject openings is not to exceed the heat flux limitations given by BCA Verification Method CV1 within the boundaries of the adjoining allotments.

Received Radiation - A limit of 20 kW/m2 of received radiation at the subject openings is

proposed to be considered, which corresponds to the level of heat flux required to ignite “normal” combustible materials found within buildings. NOTE: Clause C3.2 of the BCA does not require openings in external walls to be protected where they are located 3m or more from an allotment boundary. When applying Verification Method CV1, a distance of 3m equates to a maximum radiant heat exposure of 20 kW/m2. Where radiant heat screens are fitted to the openings, a limit of 25 kW/m2 of received radiation at the subject openings is proposed to be considered. This level of radiation represents the limitation in which non-piloted ignition of cotton fabric (e.g. curtains) occurs after prolonged exposure, as referenced in AS 1530.4-20054.

Alternative Solution 2 - Exit Travel Distances (Basement Levels)

Preliminary Fire Safety Strategy

The preliminary fire safety strategy will be based on:

The provision of fast response sprinklers throughout the basement levels in lieu of standard response sprinklers. It is proposed to demonstrate that the provision of fast response sprinklers will improve occupant cue time in the event of fire, and thus offset the additional travel distances to reach the point of choice.

The effectiveness of fire sprinklers to mitigate the development and spread of fire.

The characteristics and use of the basement levels.


Both a Quantitative and Qualitative Analysis is proposed to be undertaken to compare the Alternative Solution against the DTS Provisions of the BCA, as permitted under Clause A0.9(c) of the BCA. The Quantitative Analysis will compare the Required Safe Evacuation Time (RSET) from the basement levels for the Alternative Solution against a DTS Compliant Design. That is, RSETAlt Sol < RSETDTS.

The Qualitative Analysis will consider the characteristics and use of the basement levels, the characteristics of the occupants, and the risk of the path of travel to the point of choice being blocked or obstructed as a result of fire when compared to a DTS Compliant Design. Proposed Acceptance Criteria

The Alternative Solution is to be shown to comply with BCA Performance Requirements DP4 and EP2.2 in terms of ensuring occupants are allowed to evacuate from the basement levels safely and under tenable conditions, at least equivalent to that of a design that complies with the minimum DTS provisions of the BCA.

4 Australian Standard, Methods for fire tests on building materials, components and structures, Part 4: Fire-resistance test of elements of construction.



Alternative Solution 3 - Exit Travel Distances (Residential Levels)



The provision of an automatic smoke detection and alarm system throughout the common areas building to BCA Specification E2.2a (Clause 4) and to the relevant provisions of AS 1670.1. Smoke detectors are to be installed throughout the public corridors on the residential levels of the building and within the ground floor entry lobbies.

The provision of 240V smoke alarms within each residential unit to BCA Specification E2.2a

(Clause 3) and the relevant provisions of AS 3786-1993.

The provision of an additional heat detector within each residential unit located immediately adjacent the unit entry doors (i.e. within 1.5m), and connected back to the AS 1670.1 smoke detection system serving the building. These heat detectors will provide occupants with an earlier warning of fire within a residential unit when compared to the minimum DTS provisions of the BCA.

The provision of an enhanced building occupant warning system throughout the building,

which includes a verbal directive to instruct occupants to evacuate. Such a system exceeds the minimum DTS provisions of the BCA, and is considered to improve occupant pre-movement times in the event of an emergency.

The provision of intumescent combined fire and smoke seals to the entry doors into each

residential unit. The provision of smoke seals significantly reduces the available gap around the perimeter of the doors, through which smoke can flow from the unit of fire origin into the egress path. The required seals will have approvals to both AS 1530.7-2007 (maximum ambient and medium smoke leakage rates for single door assemblies) and AS 1530.4-2005 (for use on fire rated door-sets). Therefore the seals are expected to be capable of mitigating smoke spread into the public corridors during both the initial stages of a fire, and in the event of a fire flashover fire where temperatures can exceed 6000C. Therefore the temperature, visibility and toxicity within the public corridors in the event of fire within a residential unit is expected to be significantly improved when compared to a design that complies with the minimum DTS provisions of the BCA where fire and smoke seals are not provided.

Consideration will be given to the characteristics and use of the public corridors, which are

purely used as circulation areas, comprise of fire rated bounding construction, and are unlikely to be used for the storage of combustible materials. Further, the public corridors on each level will comprise of permanent natural ventilation openings that will permit the natural ventilation of smoke should the effects of fire from within a fire affected unit spread to the public corridors. Therefore the temperature, visibility and toxicity within the public corridors in the event of fire within a residential unit is expected to be significantly improved when compared to a design that complies with the minimum DTS provisions of the BCA where the public corridors are fully enclosed.


A Qualitative Analysis is proposed to be undertaken to compare the Alternative Solution against the DTS Provisions of the BCA, as permitted under Clause A0.9(c) of the BCA. Proposed Acceptance Criteria

The Alternative Solution is to be shown to comply with BCA Performance Requirements DP4 and EP2.2 in terms of ensuring occupants are allowed to evacuate from the residential levels of the building safely and under tenable conditions, at least equivalent to that of a design that complies with the minimum DTS provisions of the BCA.



Alternative Solution 4 - Travel via Fire-Isolated Exits



The provision of an automatic smoke detection and alarm system throughout the common areas of the building to BCA Specification E2.2a (Clause 4) and to the relevant provisions of AS 1670.1. Smoke detectors are to be installed throughout the public corridors on the residential levels of the building, and within the ground floor entry lobby and ancillary use areas.

The provision of an enhanced building occupant warning system throughout the building,

which includes a verbal directive to instruct occupants to evacuate. Such a system exceeds the minimum DTS provisions of the BCA, and is considered to improve occupant pre-movement times in the event of an emergency.

The provision of drop down smoke curtains in front of the lift landing doors within the

basement levels, to mitigate the risk of smoke spread into the entry lobby (Block A) and the covered area (Block B) in the event of fire. Further, the basement car parking levels will be fully sprinkler protected utilising fast response sprinkler heads.

Fire separating the discharge point from the fire-isolated exit from the residential units on ground floor.

The provision of alternative paths of travel from the discharge point from the fire-isolated exits on ground floor.

The characteristics and use of the entry lobby (Block A) and the covered area (Block B) on ground floor, which is purely used as circulation area, comprises of fire rated bounding construction, and is unlikely to be used for the storage of combustible materials.

Proposed Methods of Analysis

A Qualitative Analysis is proposed to be undertaken to compare the Alternative Solution against the DTS Provisions of the BCA, as permitted under Clause A0.9(c) of the BCA. Proposed Acceptance Criteria

The Alternative Solution is to be shown to comply with BCA Performance Requirement DP5 in terms of ensuring that occupants are allowed to evacuate from the building via the fire-isolated exits safely, and protected from the effects of fire. Alternative Solution 5 - Location Fire Hydrant Booster Assembly



The provision of a masonry wall directly behind the booster assembly to shield fire-fighters from flames and radiant heat from within the building. The masonry wall is to extend 2m above the finished ground level of the booster assembly, and is to extend at least 1m horizontally past each side of the booster assembly.

Reference will also be made to the current Draft version of the new AS 2419.1. Clause

7.6.1(c) of this Draft Standard states that where a fire brigade booster assembly is located remote from but more than 3.5m and less than 10m from the building facade, it shall be separated from the building by a construction having a FRL not less than 90/90/90 for a distance not less than 1m each side of the fire brigade booster assembly and from the ground to not less than 2m in height.



Whilst it is acknowledged that the new AS 2419.1 is still in Draft Format, and yet to finalized and / or Gazetted in an official capacity, it does recognize that a masonry wall that will be constructed behind the booster assembly will provide a suitable level of radiant heat protection to afford safe access to the booster assembly in the event of fire within the building.

Figure 7: Extract from the Draft AS 2419.1 Proposed Methods of Analysis

A Qualitative Analysis is proposed to be undertaken to assess the Alternative Solution against the relevant Performance Requirements of the BCA, as permitted under Clause A0.9(b)(ii) of the BCA. Proposed Acceptance Criteria

The Alternative Solution is to be shown to comply with BCA Performance Requirement EP1.3 in terms of ensuring that the location of the fire hydrant booster assembly does not impede fire brigade operations. That is, the attending fire brigades must be capable of safely accessing the booster assembly in the event of fire within the building. Alternative Solution 6 - Access to Sprinkler Valve Room



The provision of fire sprinklers throughout the basement levels, including the use of fast response sprinklers, which is expected to mitigate the development and spread of fire.

Having the sprinkler control valve located within the fire hydrant pump room, which is

accessed directly from a stairway that will be fire-isolated from the basement levels. Comparison to a fire hydrant pump room, which is permitted to be accessed from a fire-

isolated exit in lieu of directly from an open space. The provision of Block Plans and signage to ensure the location of the fire hydrant pump

room / sprinkler valve room is readily identifiable to the attending fire brigades. Proposed Methods of Analysis

A Qualitative Analysis is proposed to be undertaken to assess the Alternative Solution against the relevant Performance Requirements of the BCA, as permitted under Clause A0.9(b)(ii) of the BCA. Proposed Acceptance Criteria

The Alternative Solution is to be shown to comply with BCA Performance Requirement EP1.4 in terms of ensuring that the attending fire brigades are afforded safe and quick access into the fire hydrant pump room / sprinkler valve room.



REQUIRED FIRE SAFETY SYSTEMS The following fire safety systems will be required to be installed throughout the subject development:

Fire hydrants

Fire hose reels

Fire sprinklers (basement levels only)

Portable fire extinguishers

Automatic smoke detection and alarm system

Building occupant warning system

Emergency lighting and exit signs NOTE: The above list may change or vary during the design and development process, and / or as a result of the future Fire Engineering Report. CONCLUSION In consideration of the above, it is concluded that Alternative Solutions can be developed to the DTS provisions of the BCA to ensure the proposed development can achieve compliance with the relevant Performance Requirements of the BCA. Yours Faithfully Innova Services Pty Ltd

Jason Powell Director C10 Accredited Fire Engineer (BPB0801) MIEAust, CPEng

PROVISION FOR FIRE ENGINEERING (FOR DA SUBMISSION)€¦ · Exit Travel Distances - BCA Clause D1.4...

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