NCC Tutor lesson - Using the fire safety provisions in NCC Volume Two

Slide 1:

Welcome to Using the fire safety provisions in NCC Volume Two

Slide 2:

The focus of this presentation is on the specific fire safety provisions in the NCC Volume Two.

Slide 3:

This is what you will learn about in this presentation. Where fire safety is covered in 
NCC Volume Two, Fire safety related Performance Requirements, Fire safety DTS Provisions in Section H of Volume Two and the ABCB Housing Provisions Standard (Housing Provisions), Assessment Methods and Verification Methods, Other useful resources.

Slide 4:

Fire safety in NCC Volume Two: Governing and Performance Requirements

The 2 Performance Requirements in Part H3 of NCC Volume Two reflect the key concerns for fire safety in Volume Two of the NCC. Reducing the risk of a fire spreading between buildings or structures. Warning occupants in the event of a fire so that they can evacuate safely. Protecting the building itself is not actually a primary aim of the NCC fire safety provisions. The building can burn down as long as the occupants can evacuate safely and the fire does not spread to other buildings.

The DTS Provisions in Part H3 also reflect these key concerns, with particular DTS Provisions that relate to the different factors that can affect the spread of fire from or to a building, and one that relates to warnings.

The 4 relevant Performance Requirements in Part H7 relate to heating appliances installed in a building that can increase the risk of fire.

Buildings in alpine areas, with key concerns being ensuring that exits are not blocked in snow conditions and ensuring that there is space for emergency vehicles.

Buildings in bushfire prone areas, that must meet additional standards to reflect the risk of bushfires.

The construction of private bushfire shelters.

The DTS Provisions in Part H3 provide a means for complying with 3 of these 4 Performance Requirements.

There are no relevant DTS Provisions for H7P6 Private bushfire shelters, but there is a Verification Method in Part H7 that can be used. Verification Methods are discussed later in the presentation.

They should remember that they don’t have to use the DTS Provisions but can develop a Performance Solution instead. Or they can use a combination of a DTS Solution and a Performance Solution.

Slide 5:

Fire safety in NCC Volume Two: DTS pathways for compliance 

In Section H of Volume Two, some DTS Provisions contain more than one pathway for compliance. Usually, the first of these pathways will be by reference to a relevant Australian Standard (or other similar referenced document). The second will be by referencing a Part or Section of the ABCB Housing Provisions Standard – aka the Housing Provisions. 

The fire safety related DTS Provisions in Volume Two are found in Part H3 Fire Safety and Part H7 Ancillary provisions and additional construction requirements. You will find they contain references to the Housing Provisions. 

The Housing Provisions contains the majority of the DTS Provisions for Volume Two, including those relevant to fire safety. If a DTS Provision in Volume Two does not reference the Housing Provisions, then the Housing Provisions cannot be used for that provision. 

The Housing Provisions contains DTS Provisions considered to be acceptable forms of construction that meet the requirements for complying with Parts H1 to H8 of Volume Two. That is, they comply with the Performance Requirements listed in Parts H1 to H8 of Volume Two. 

The Housing Provisions must be applied in line with each of the following. Section A Governing Requirements of Volume Two; Any conditions on the Housing Provisions set out in the DTS Provisions of Volume Two where referenced; and the scope clause at the start of each Section of the Housing Provisions. 

Slide 6:

Fire safety Performance Requirements in Part H3 of NCC Volume Two

H3P1 Spread of fire. SAH3P1, Variation applies in South Australia only. “A brush fence means a fence or gate that is primarily constructed of Boombrush (Melaleuca Uncinata)

A Class 1 Building. This applies only to a Class 1 Building not to Class 10 Buildings; may need to consider siting materials and construction methods to reduce the risk that fire will spread to or from a building or boundary.

Associated Class 10 Building. Protect the Class 1 building from fire from another Class 1 building on the same block. For example, a granny flat or sleepout. This does not apply to an associated Class 10 building, such as a garage, carport shed or fence on the same property

The allotment boundary. Is the legal edge of the property, may or may not have a fence or other clear delineation, this applies even if there are currently no buildings on the neighbouring property or properties.

This is Figure H3P1. A Class 10a building Applied to Class 10a building on the property. For example, a private garage, shed or carport, must not increase fire risk to nearby Class 2 – 9 buildings.

H3P2 Automatic warning for occupants. A Class 1 Building Applies only to a Class 1 Building, not to Class 10 buildings or structures.

Automatic warning, “automatic means designed to operate when activated by heat, smoke or fire sensing device”. Typically, a smoke alarm, but this is not the only way of meeting this requirement.

Slide 7:

What are the DTS Provisions in Part H3 Fire safety?

Part H3 Fire safety contains DTS Provisions for complying with the fire safety related Performance Requirements. That is H3P1 Spread of fire and H3P2 Automatic warning for occupants.

Most of the DTS Provisions in Part H3 reference the DTS Provisions the Housing Provisions. 

Many of the provisions relate to the separation distances between buildings and structures and construction standards for situations in which these distances are not met, i.e. when the distance between buildings is less than the specified minimum distance.

There are also provisions relating to separating walls between sole occupancy units (SOUs), to ensure that they resist the spread of fire.

Part 9.2 Fire separation of external walls talks about “encroachments” - An encroachment is something that advances “beyond the usual or proper limits”. In this case, it means parts of the building that extends within the required separation distances. Some building elements, such as gutters and eaves can extend within these limits, as long as they are built to the required fire safety standard.

“appurtenant” structures - An appurtenance is defined as “something accessory to another and more important thing” (Macquarie Dictionary). So, a structure that is appurtenant to a building, is related to it in some way. In this Part, the term often refers to a garage that is associated with a house. A house might need to be protected from the spread of fire from an appurtenant structure such as a garage associated with the house, or from a non-appurtenant structure, such as a shed on a neighbouring property boundary.

Part 9.5 Smoke alarms and evacuation lighting talks about requirements for smoke alarms in Class 1a and Class 1b buildings. Requirements for emergency lighting in Class 1b buildings.

When people are sleeping their sense of smell does not operate effectively, and they may not detect smoke. Part 9.5 also provides helpful explanatory information relating to smoke alarms. 

When deciding on the position of smoke alarms it is important to remember that they are intended to detect smoke before it reaches the sleeping occupants of the building. This is to ensure that occupants wake up and to allow time for the occupants to evacuate the building. Generally, this requires the smoke alarm to be located in a corridor between sleeping areas and living areas.

In a Class 1b (i.e. a boarding house or short term accommodation), a lighting system must also be installed (and be activated by the smoke alarms) to assist occupants to evacuate in the event of a fire.  This is because the occupants are less likely to be familiar with the layout of the building and won’t necessarily be able to locate the exits easily in the case of a fire.

Figure 9.5.2b (Housing Provisions) illustrates an example of how smoke alarms should be located in a Class 1a building, where bedrooms are located in separate areas.

Figure 9.5.3 (Housing Provisions) illustrates an example of how smoke alarms should be located in a Class 1b building, where bedrooms are located in the same area.

Figure 9.4.2 (Housing Provisions) illustrates an example of separating wall and floor construction for a Class 1a and Class 10a building, and requirements for fire protection. 

Slide 8:

Interpreting Part 9 Fire safety in the Housing Provisions

Question 1: According to Part 9.2 of the Housing Provisions, what distances are relevant when you are trying to determine whether an external wall of a Class 1 building requires fire-resisting construction? 

Answer 1: Part 9.2.1 External walls of Class 1 buildings Must comply with the provisions of Part 9.2.3 (Fire-resisting construction) if the wall is less than (a) 900 mm from an allotment boundary, other than the boundary adjoining a road or other public space, or (b) 1.8 m from another building on the same allotment other than a Class 10 building associated with the Class 1 building or a detached part of the same Class 1 building.

Question 2: According to Part 9.2 of the Housing Provisions, what options do you have for the materials used in an external wall that must have a fire-resisting construction?

Answer 2: Part 9.2.3 Construction of external walls, Clause (2). An external wall that must be fire-resisting can be of materials with an FRL of not less than 60/60/60 when tested from the outside, OR masonry-veneer construction in which the external masonry veneer is not less than 90 mm thick, OR masonry construction not less than 90 mm thick

Question 3: According to Part 9.3 of the Housing Provisions, what requirements apply to combustible roof lights that are installed in a roof or part of a roof that is required to have a non-combustible covering?

Answer 3:

Part 9.3.3 Roof lights. The roof lights must have an aggregate area not more than 20% of the roof or part of the roof, and be not less than 900 mm from the vertical projection of a separating wall extending to the underside of the roof covering

Question 4: According to Part 9.5 of the Housing Provisions, what Australian Standards apply to smoke alarms installed in Class 1 and Class 10 buildings, in different circumstances?

Answer 4: Part 9.5.1 Smoke alarm requirements. Smoke alarms must comply with AS 3786 Smoke alarms using scattered light, transmitted light or ionization, OR AS 1670.1 Fire detection, warning, control and intercom systems – System design, installation and commissioning – Fire, when the smoke alarm is installed in a private garage where the use of the area is likely to result in spurious signals (provided that smoke alarms that comply with AS 3786 are installed elsewhere in the Class 1 building).

Slide 9:

Where would you place smoke alarms…In the Class 1a building shown on the right, to comply with the Part 9.5 of the Housing Provisions? Interconnected smoke alarms would be required in both hallways that lead to bedrooms

Slide 10:

Fire Safety Performance Requirements in Part H7 of NCC Volume Two

H7P3 Heating Appliances. This variation applies in Tasmania only. Heating appliance and its associated components. This applies to the appliance itself and all associated components. For example, ductwork, piping, brackets, stands and electrical components.

H7P4  Buildings in alpine areas. An Alpine area is area where snow loads are significant. Areas that receive significant snowfall which is likely to accumulate in the ground. Located in NSW, Victoria and Tasmania. External Trafficable structures could include roads or laneways, bridges or walkways, driveways, balconies or decks with exits or stairways from the building.

Obstruct a means of egress means snow or ice falling from the roof of a building can restrict people’s ability to enter or exit the building, causing a problem for evacuation during an emergency. Snow or ice from a building cannot fall onto other properties or roadways or public spaces, obstruct access from that building or any other building.

H7P5  Buildings in bushfire-prone areas. Tas H7P5 is an NCC variation applied in Tasmania. Adds a requirement to provide access for emergency vehicles and water supply for fire fighting. The designated bushfire-prone area is land that is subject to, or likely subject to, bushfires. NSW variation for this defined term can be found in Schedule 5. Bushfire-prone areas are legally designated by state and Territory governments. 

H7P6 – Private bushfire shelters. A tenable environment. The shelter must provide an environment free of flame, heat, smoke and toxic gases for the number of people who might be expected to use it for as long as necessary. How long depends on consideration of the factors listed.

Applications. H7P6 only applied to Class 10c buildings, private bushfire shelters. That is, bushfire shelters associated with private residential buildings, such as Class 1 buildings.

Notes. No DTS Provisions included in Volume 2 or the Housing Provisions to meet this Performance Requirement. Refer to the ABCB Performance Standard for Private Bushfire Shelters.

Slide 11:

Verification Methods in Part H3 Fire safety in Volume Two

Which of the Verification Methods in Part H3 could you use in each of the following circumstances?

Question 1: To verify compliance with requirements to avoid the spread of fire between buildings on adjoining allotments? Answer 1: H3V3 Avoidance of the spread of fire between buildings on adjoining allotments [H3P1(2)]

Question 2: To verify compliance with requirements to avoid the spread of fire between buildings on the same allotment? Answer 2: H3V1 Avoidance of the spread of fire between buildings on one allotment [H3P1(1)(a)]

Question 3:      To verify compliance with requirements to avoid the spread of fire from an allotment boundary? Answer 3: H3V2  Avoidance of spread of fire from allotment boundary [H3P1(1)(b)]

Slide 12:

What are the DTS Provisions in Part 12 Ancillary provisions of the Housing Provisions?

Part 12 Ancillary provisions of the Housing Provisions contains DTS Provisions for complying with the relevant DTS Requirements of Part H7, Volume Two. 

They cover 2 of 4 of the fire safety related Performance Requirements in H7, that is H7P3 Heating appliances, and H7P4 Buildings in alpine areas.

Slide 13:

Assessment Methods for fire safety in NCC Volume Two

Whether you choose to use a DTS Solution or a Performance Solution or a combination of them, you may need to provide some evidence that the proposed solution complies with the Performance Requirements.

The NCC recognises 4 valid ways of assessing possible compliance solutions, which are shown on the slide.

All 4 methods can be used to demonstrate compliance with all or part of the Performance Requirements when you are using a Performance Solution. 

Evidence of suitability and Expert Judgement can be used when you are using a DTS Solution.

The various fire safety related Sections and Parts of NCC Volume Two include a number of relevant Verification Methods, each of which can be used in certain circumstances.

Slide 14:

Example 1: Ensuring fire safety

Location: Urban Australia

The key considerations in this case would relate to determining where the boundaries of the block are and which ones present a fire risk.

The requirements that apply to buildings or structures of different classes on the same and neighbouring blocks. E.g. the granny flat versus a garage. Note that no setback distances are given, but you can still discuss the impact of different setback distances, e.g. less and more than 900 mm from the boundary. 

The open fireplace and chimney in the right hand building, that will require additional construction to ensure fire safety.

Slide 15:

Example 2: Ensuring fire safety. Location: Thredbo, NSW. The key considerations in this case would relate to the building is a Class 1b building.

Location in an alpine area means the provisions in H7P4 apply.

Possibly located in a bushfire prone area. If so, then H7P5 also applies. (Also need to check NSW Government designation of bushfire-prone areas.)

The open fireplace in the lounge area which would require different construction to reduce the risk of the spread of flames, smoke etc. the provisions of H7P3 apply. DTS Provisions would include fire resistant construction underneath the fireplace/stove, and a flue above it, which would require appropriate construction to prevent the escape of flames, embers, heat, smoke or gases.

Placement of smoke alarms, especially in the corridor which leads to 4 of the bedrooms. H3P2 applies.

Need for emergency lighting and where this might be placed.

While no neighbouring buildings or roads are shown, you could still discuss the need to keep exit pathways clear and space for emergency vehicles.

Slide 16:

Other useful resources:

Standards are mandatory, when referenced within the NCC. 

For example, if you choose to use the DTS Provisions of H7D4 to comply with requirements for a steel-framed building in a bushfire prone area then compliance with the NASH Standard would be mandatory OR alternatively, AS 3959.

It is possible to use an alternative Performance Solution instead.

Handbooks and videos are non-mandatory resources that provide guidance and help, but nothing in them needs to be complied with in order to comply with the NCC.

Slide 17:

Summary. Volume Two. Performance Requirements. Part H3 Fire safety. Part H7 Ancillary provisions and additional construction requirements

Volume Two. DTS Provisions. Part H3 Fire safety. Part H7 Ancillary provisions and 
additional construction requirements

Housing Provisions. Part 9 Fire safety. Part 12 Ancillary provisions

Slide 18:

Key points

Overall aim is to prevent the spread of fire from or to other buildings/structures.

Warn occupants of a fire to allow for safe evacuation.

The Housing Provisions contains relevant fire safety related DTS Provisions - referenced in NCC Volume Two 

If a DTS Provision in Volume Two does not reference the Housing Provisions, then the Housing Provisions cannot be used for that provision. 

Fire safety requirements can be met using DTS Provisions (including the Housing Provisions) or a compliant Performance Solution

Section A Governing Requirements must also be complied with

Slide 19:

Thank you for your time. That brings our presentation on using the fire safety provisions in NCC Volume Two to a close. If you’d like more information please visit abcb.gov.au