Part A1 Interpretation

Where a definition in the NCC has been considered to be self-explanatory, it has not been included in this guide.

Accessible

Used in provisions regarding access for people with a disability. See Part , , and .

Accessway

A path of travel suitable for use by people with a disability. It is an abbreviation from AS 1428.1 which defines the term continuous accessible path of travel (accessway) as an uninterrupted path of travel providing access to all accessible facilities.

Accredited Testing Laboratory
An Accredited Testing Laboratory is an organisation authorised to give an opinion on the use of a material, product, construction or design.

Testing authorities are accredited by the National Association of Testing Authorities (NATA). NATA publishes a directory explaining which authorities are accredited to carry out what tests. International organisations are also recognised by NATA; a directory also details these organisations.

Paragraph (c) of the definition prescribes that valid test reports from organisations which were recognised as being Accredited Testing Laboratories under legislation at the time the test was undertaken may still be accepted.

Aged care building

The definition describes a residential building for the accommodation of the aged. These buildings are the homes of the residents. To be an aged care building the residents must be provided with personal care services and 24 hour assistance to evacuate. The definition applies to Class 9c buildings. If a building does not satisfy the definition, then for NCC purposes it is not an aged care building and cannot be constructed as one. Such a building would potentially be an ordinary Class 3 or 9a building and would need to comply with the relevant provisions.

The NCC contains a number of specific provisions for Class 9c buildings.

Air-conditioning

This definition relates to the context in which it is used and does not necessarily cover special cases such as when air is only humidified, filtered or otherwise treated. The intent is to cover a system, including its components, that provides a controlled internal environment in a building where the primary purpose for controlling the environment is maintaining occupant comfort. It should be noted that the occupants may not always be comfortable, but the conditions are sufficiently tolerable for occupants to minimise their use of services for heating and cooling. It does not cover a system that primarily and directly serves equipment such as that used for cold rooms or hot rooms, where the temperature is above or below normal comfort levels. Examples would include such rooms in a butcher's shop, laboratories, fruit storage rooms, or the like.

The definition also does not apply to a system that is provided to maintain conditions for the effective operation of equipment or processes, such as equipment used in a Class 8 electricity network substation or an air-conditioning system specifically designed to serve computers in a data centre. These exemptions recognise that these installations have specific air quality, heat load and temperature limits critical to the operation of sensitive equipment and processes.

The term is used in the Deemed-to-Satisfy Provisions through the defined term 'conditioned space' to require energy efficiency features including envelope treatment.

Although the definition is termed air-conditioning, the conditioning may be achieved without treating the air forced into and through the space. The air in the space may be conditioned by hot or cool surfaces. This includes residential heating systems, such as gas and combustion appliances, that are not always considered to be air-conditioning in the traditional sense. The conditioning may also be achieved by evaporative coolers.

Alpine area

Areas generally subject to snow, or places where snow can add a significant load to buildings, or cause difficulties with egress. See Figure G4.1.

Alternative Solution

Has the same meaning as Performance Solution. See part A0.

Ancillary element

An ancillary element is a building component, material or article that is not integral to the construction of another building element. Its function is secondary in nature and should not form part of the building element or feature to which it is supplementing. An ancillary element does not add significantly to the building’s fire load or is unlikely to significantly contribute to the spread of fire because of its size, construction, location and so on.

Annual energy consumption

This is the amount of energy calculated to be consumed under certain specific conditions in consideration of operating profiles, internal loads and plant efficiencies. It is used in that compares the calculated energy consumption with that of a complying reference building. It should not be considered a prediction of the actual energy consumption of an actual building as there could be major differences in the conditions such as the internal loads of the building and the hours of operation. It differs from annual energy load because it is affected by the type of heating or cooling appliance used, for example, heating by a reverse cycle air-conditioner uses less than half the energy that a gas fired heater would use to meet the same annual energy load.

Appropriately qualified person

An appropriately qualified person is a person recognised by an authority having jurisdiction as qualified to provide evidence under A2.2 that a material, product, form of construction or design complies with a Performance Requirement or Deemed-to-Satisfy Provision. The person does not necessarily need to be licenced or registered unless required by the State or Territory regulatory system.

Assembly building

Describes buildings classifiable as Class 9b buildings.

Assessment Method

See Part .

Atrium and atrium well

An atrium can pose unique fire and smoke hazards. As such, the NCC lists Deemed-to-Satisfy Provisions for their construction.

An atrium is created by the connection of 2 or more storeys by an opening in the floor. It also includes the space not fire-separated from the rest of the building. The atrium well is that part extending through the openings in the floors. See Figure A1.1(AT).

Average recurrence interval

Refers to a set number of years when a rainstorm of a 5 minute rainfall duration intensity can statistically be expected to occur. If a 10-year period is set, the expected rainstorm would be less intense than if a 50-year period is set. Statistically, a heavier storm is more likely to occur every 50 years than every 10 years.

This term is used in the design of stormwater drainage systems. See and . Also refer to AS/NZS 3500, or Australian Rainfall and Run-off, published by the Institution of Engineers (Australia).

Average specific extinction area

A test in accordance with AS/NZS 3837 determines the average specific extinction area of a material. A lower value indicates better performance.

Backstage

There are special provisions for backstage areas because of the high fire load posed by scenery and props.

Building Solution

The term Building Solution has been replaced with the terms Deemed-to-Satisfy Solution and Performance Solution. The defined term has been retained as some jurisdictions may still reference the term in their legislation.

Carpark

A carpark can be a whole, or part, of a building. It is any building not associated with a Class 1 building and contains more than three vehicle spaces on one storey. It is not a “private garage”.

Cavity wall

Used only in Verification Method and defines wall construction which includes a drained cavity. The required cavity can consist of clear unobstructed space or cavity battens. However, where cavity battens are used the 'compliance' component of the Verification Method must be considered to ensure water does not pool on battens or other cavity surfaces.

The Verification Method does not restrict the use of horizontal battens, provided the battens have the ability to facilitate the removal of water which may enter the cavity.

The intention of the Verification Method is to provide a means of verifying compliance with for new and innovative products. Therefore, prescriptive requirements such as what constitutes a vented cavity or required cavity depth has not been provided.

A cavity wall is illustrated in Figure A1.1(CW).

Certificate of Accreditation

A Certificate of Accreditation is issued by a State or Territory accreditation authority and is evidence that a building material, method of construction or design (subject to any specified conditions or limitations) is accepted within that State or Territory as complying with the NCC.

Certificate of Conformity

A Certificate of Conformity issued under the ABCB's voluntary CodeMark Australia scheme is evidence that a building material, method of construction or design (subject to any specified conditions or limitations) is accepted within all States and Territories as complying with the NCC. A Certificate of Conformity issued under the previous CodeMark scheme can still be used as supporting evidence while the certificate remains valid

Certification body

A certification body is a person or organisation authorised to give an opinion on the use of a material, product, form of construction or design.

Certification bodies, commonly referred to as Conformity Assessment Bodies (CABs), are accredited by the Joint Accreditation System of Australia and New Zealand (JAS-ANZ).

CABs issue certificates under an industry-operated scheme. This differs to the CodeMark Australia or CodeMark Certification Scheme.

Climate zone

Energy efficiency measures vary from location to location depending upon the local climate. For simplicity, locations with approximately similar climates have been combined into eight climate zones and they are shown in both map format and tabular format for major cities. Where greater clarity is needed, an enlargeable version of the map on the ABCB web page shows how the climate zone boundary aligns, in most cases, with a local government boundary.

These climate zones were based on a list of six zones that were developed by the Bureau of Meteorology (BOM), with the addition of a third temperate zone and the inclusion of the existing NCC Alpine areas. The basis of each climate zone is shown in the following table:

Where appropriate, the map was then adjusted for ease of administration, by aligning the climate zone boundaries with local government areas where local knowledge identified the impact of topographical features such as an escarpment or significant micro-climate variation, and where the type of construction required in another zone was felt to be more appropriate for a particular location. There were some further minor adjustments made to the zones following thermal modelling tests of a typical building around the country.

The zones are considered sufficiently accurate for Deemed-to-Satisfy Provisions. More extensive climate data is available when using energy analysis software.

Combustible

A test done in accordance with AS 1530.1 will determine if a material is combustible. If materials used in an assembly contain combustible components, then the assembly is combustible. See also C1.9.

Common wall

A common wall can be on one allotment or straddle a boundary. However, it must be common to adjoining buildings. Some jurisdictions consider a “party wall” a common wall. See your building regulatory body. Where the expressions “internal wall” and “external wall” are used, they are specifically defined to exclude a “common wall”.

Conditioned space

The definition of a conditioned space is included to limit the application of the provisions where a commercial or industrial building has only a small amount of air-conditioning or where a non-habitable room has only a small local heater, such as in a bathroom.

It also clarifies that a conditioned space is one likely to be air-conditioned rather than one that is air-conditioned. For example, one would expect offices and shops to be fully air-conditioned at some time during their life for reasons of productivity, customer comfort or for the protection of products, even though they may not be air-conditioned initially. In some cases, chilled and heated water may be reticulated through duct risers as part of the building design to enable conditioning to be provided as part of a later fit-out.

A conditioned space may include a ceiling or underfloor space that is open to the conditioned space such as a space separated by only a perforated or grille ceiling or floor where the space is a supply air or return air plenum.

While, for the sake of the Deemed-to-Satisfy Provisions, it may be assumed that all Class 3 and Class 5 buildings and most Class 6 buildings will be fully air-conditioned at some time during their life, this may not be the case with all Class 6 buildings and some Class 7, 8 and 9b buildings that do not have a conditioned space or are only partially conditioned. Buildings that typically are not conditioned could be a carpark, market, large purpose-built hardware store, garden centre or foundry. Those buildings, or parts of buildings, that may be partially conditioned could include a check-out counter in a purpose-built hardware store and workstations in a factory or aircraft hanger or even a church.

A capacity of 15 W/m² (4.3 MJ/hour) for either heating or cooling has been set as the minimum threshold for the definition of air-conditioning. The criterion of 15 W/m² is between 10% and 20% of the capacity of a typical heating or cooling system providing comfort temperatures to the full area of a building. Typically, the cooling needed for a building in climate zone 7 would be of the order of 100 W/m² to 120 W/m² and in climate zone 5, the heating would be of the order of 50 W/m². With a heat pump air-conditioner, the input power rates for climate zone 7 for cooling would be 30 W/m² and for climate zone 5 for heating, 20 W/m². Warmer climate zones have higher cooling needs and colder climate zones have higher heating needs. Typically, evaporative coolers would be under the 15 W/m² threshold.

Note that the definition of a conditioned space refers to the temperature in the space being controlled by air-conditioning. The definition of air-conditioning excludes services that cool or heat cold rooms and hot rooms. Therefore the NCC energy efficiency provisions do not apply to these process related rooms.

A room that is not conditioned in its own right, such as one providing a return air path or exhaust air path for conditioned air from an adjoining space, should be considered as a conditioned space. This means that the walls, floor and ceiling between it and an adjoining conditioned room are not part of the envelope and so do not require insulating. Likewise, in certain circumstances some internal spaces could be indirectly conditioned by air pressurisation occurring in adjoining areas. Expert advice may be needed to determine which spaces are indirectly conditioned.

Construction activity actions

This definition is used in Part B and only refers to construction activities that may have an effect on the final building design such as stacking of materials or floor to floor propping.

Critical radiant flux

A test in accordance with AS ISO 9239.1 determines the critical radiant flux of a material. A higher value indicates better performance.

Curtain wall

A curtain wall is a facade fixed to the exterior of the building and may not be supported within frames at each storey. See Panel Wall.

Deemed-to-Satisfy Provisions

The Deemed-to-Satisfy Provisions make up the bulk of the NCC. The Deemed-to-Satisfy Provisions are deemed to satisfy the Performance Requirements. See Part .

Deemed-to-Satisfy Solution

Means a solution which uses the Deemed-to-Satisfy Provisions to demonstrate compliance with the Performance Requirements. See Part .

Defined flood level

See Figure A1.1(FLO).

Designated bushfire prone area

Bushfire prone areas may be designated by a power under legislation. See your building regulatory body.

Early childhood centre

On 1 January 2012, the National Quality Framework was established under an applied law system comprising the Education and Care Services National Law Act 2010 and Education and Care Services National Regulations 2011 and will apply to most long day care, family day care, outside school hours care and preschools (or kindergartens).

A national applied law system is a way of establishing national laws whereby a host jurisdiction (in this case Victoria) passes a law (the Education and Care Service National Law Act 2010) and other jurisdictions adopt that law or pass corresponding legislation.

As a consequence a number of Parts in the NCC were aligned with the National Quality Framework.

The early childhood centre defined term refers to the term 'centre-based'. Under the definitions contained in Chapter 1 of the Education and Care Services National Regulations 2011, a centre-based service means an education and care service other than a family day care service.

Effective height

Is a measure of the height of a building. It is used to determine when various provisions are required to be implemented and when certain concessions cannot apply.

Effective height is the vertical distance between:

• the floor level of the topmost storey in the building (excluding a storey which only contains equipment as listed); and
• the floor level of the lowest storey which is included in a determination of rise in storeys (see ).

Electric passenger lift

An electric passenger lift may also be a combined electric passenger and goods lift.

Electricity network substation

Electricity network substations are buildings containing high and low voltage equipment that provide essential electricity to a district or part of a city. They may be stand-alone buildings or located within multi-classified buildings. These installations provide an essential public service to the community on which other essential services such as water supply depend. Consequently they are licenced entities which differentiate them from a customer substation that supplies electricity only to the dedicated building in which it is contained.

Electrohydraulic passenger lift

An electrohydraulic passenger lift may also be a combined electrohydraulic passenger and goods lift.

Envelope

In the NCC, this term is not limited to the building’s outer shell, but also includes those continuous elements that separate a conditioned space from a non-conditioned space. For example, the floor between a plant room and an office space or the wall between a carpark and a shopping centre may be part of the envelope, rather than the outer shell. A non-conditioned space may be included within the envelope under certain circumstances.

Equivalent

A Performance Solution may achieve compliance with the Performance Requirements by achieving equivalence with the Deemed-to-Satisfy Provisions.

Evacuation route

The path a person uses to evacuate a building. It starts at the most remote part of a building and finishes at a “safe place”. This can be in the building, or a road or open space. It is not always the point of exit from a building.

An evacuation route includes the evacuation path within a sole-occupancy unit of a Class 2 or Class 3 building or Class 4 part of a building, as well as an exit from such a unit. This term is different from a path of travel to an exit, which begins at the door to such sole-occupancy units.

Evacuation time

Is the calculated time from when an emergency begins until the last occupant reaches a “safe place”.

It includes the time taken for any alarm to detect a fire and give warning. Added to this is the time taken for occupants to start to evacuate the building.

This “time” will depend on a number of factors, some of which may be influenced by an "emergency management system", including:

• the type of alarm or warning given;
• whether the occupant initially recognises the alarm or warning;
• whether the occupant decides to investigate or ignore the alarm;
• whether the occupant decides to warn other people in the building;
• the time taken for all occupants to move through the building until reaching a “safe place”.

Exit

An exit can be any of the building elements listed. It must lead to a road or open space or a horizontal exit leading to another fire compartment.

An exit starts at the beginning of the first relevant building element listed in the definition.

The exit finishes when a person reaches, as the specific circumstances require:

• a road or open space;
• in the case of a horizontal exit, another fire compartment, which in turn leads to a road or open space; or
• in the case of a non-fire-isolated stairway or ramp, the level providing direct egress to a road or open space.

Expert Judgement

Expert judgement may be used to assess a Performance Solution or Deemed-to-Satisfy Solution against the relevant Performance Requirements, or against the Deemed-to-Satisfy Provisions if use is being made of an equivalence Assessment Method.

External wall

An external wall is on the outside of a building and usually requires weatherproofing ().

It is possible for a wall to be partially an external wall and partially an internal wall. (See Figure A1.1(EW)). Where the expressions “internal wall” and “external wall” are used, they exclude a “common wall”.

Fabric

This includes all of the non-service elements of a building such as the roof, walls, glazing and floor, that impact upon the building’s thermal performance. The fabric may impact upon a building’s thermal performance through its insulating ability, or through its thermal inertia or thermal capacitance, which is the ability to slow energy flow and so delay or reduce the transfer of heat.

Fan motor power

The fan motor power is the amount of electrical input power to the motor of a fan motor, transmission (if present) and impeller excluding the control gear. This means that it is the power a motor of a fan needed in order to drive the fan and to also overcome any motor, drive or impeller losses. However, it does not include any losses from control devices such as a Variable Speed Drive (VSD). See Figure A1.1(FMP) for an example of the measurement of fan motor power in three common fan configurations.

Farming

This definition sets out activities which, for the purposes of the NCC, constitute farming and is mainly used to determine whether a building can be considered a farm building or a farm shed.

This definition relates to the context in which it is used and should be read in conjunction with farm building, farm shed, and farm vehicle definitions for appropriate application of the NCC Deemed-to-Satisfy Provisions.

Farm building

Buildings used for farming-type purposes are often very diverse in nature, occupancy and use. There are a number of conditions in this definition to outline the specific instances where a Class 7 or Class 8 building can be considered a farm building for the purposes of the NCC. This is to ensure that the Deemed-to-Satisfy Provisions for farm buildings are appropriate for a particular building in question.

The definition sets out three main criteria that a building must meet for it to be considered a farm building. These criteria can be described as:

• the use and location of the building;
• the maximum number of occupants and occupant density in the building; and
• a maximum floor area of the building.

It is recommended that this definition be read in conjunction with the definition of ‘farming’.

Refer to for specific requirements for farm buildings.

Farm shed

Buildings used for farming-type purposes are often very diverse in nature, occupancy and use and farm sheds can be generally considered as very basic buildings used for farming that are unlikely to contain people most of the time. Farm sheds could be used to protect stock from the elements, store hay or produce, or house farm vehicles when not in use. They also may not be fully enclosed.

There are a number of conditions in this definition to outline the specific instances where a Class 7 or Class 8 building can be considered a farm shed for the purposes of the NCC. This is to ensure that the Deemed-to-Satisfy Provisions for farm sheds are appropriate for the particular building in question.

The definition sets out five criteria that a building must meet for it to be considered a farm shed. These criteria can be described as:

• single storey;
• occupied infrequently and for relatively short periods of time;
• use and location of the building;
• maximum number of occupants in the building; and
• a range of allowable floor areas.

It is recommended that this definition be read in conjunction with the definition of ‘farming’.

Refer to for specific requirements for farm sheds.

Farm vehicle

This definition outlines that where a vehicle is used in relation to farming (see definition of farming) it can be considered a farm vehicle for the purposes of the NCC.

Along with other criteria, the definitions of farm building and farm shed include buildings used to store one or more farm vehicles.

Refer to for specific requirements for farm buildings and farm sheds.

Fire brigade

This term only refers to statutory authorities established under an Act of Parliament having as one of its functions the protection of life and property from fire and other emergencies. It may be a professional brigade with full-time firefighters, or a volunteer brigade. Many companies employ their own private fire services. The standard of these private fire services varies greatly. They are excluded from the definition of a fire brigade.

Fire compartment

A fire compartment contains walls, floors and the like creating a compartment (or “box”) of any shape used to limit the spread of fire to another compartment or part of a building.

If there are no distinct fire barriers erected, then the whole building forms a fire compartment.

If a Performance Solution is used, the building elements used to form a fire compartment must have appropriate fire separation from the remainder of the building as determined by fire engineering principles. Note that FRLs are only used in the Deemed-to-Satisfy Provisions.

If the Deemed-to-Satisfy Provisions of Part are used, the building element used to form a fire compartment must have the fire-resistance level (FRL) of a fire wall required by .

Sole-occupancy units are not generally regarded as fire compartments except for for fire hose reels.

Fire hazard properties

A material's fire hazard properties is an indication of its susceptibility to the effects of flame or heat, particularly during the early stages of a fire.

Fire-isolated passageway

A fire-isolated passageway protects people within a passageway from fire while evacuating. The whole passageway must be fire-protected from a fire outside the passage, including the floor, walls, ceiling, roof, any doors or other openings. The Deemed-to-Satisfy Provisions for fire-isolated passageways are in . The provisions relating to the protection of openings are in .

Fire-isolated ramp

See fire-isolated passageway.

Fire-isolated stairway

See fire-isolated passageway.

Fire-protected timber

Used for the concessions under , fire-protected timber must comply with and may be used in certain situations where a building element is required to be non-combustible.

Fire-protective covering

While not fire rated, these elements have been found to provide nominal protection from the spread of fire of at least 20–30 minutes.

The NCC lists materials deemed to be fire-protective coverings. The fixing in each case must accord with normal trade practice. There must be no gaps at the joints in the sheets, and the joints must be sealed in the usual manner. Standard grade 10 mm or 13 mm plasterboard is not acceptable as a fire-protective covering.

Fire-resistance level (FRL)

Used only in the Deemed-to-Satisfy Provisions, the FRL of a building element is determined by conducting the Standard Fire Test on a prototype in accordance with AS 1530.4.

Fire-resisting

Applies to fire-resisting building elements, including structural members and non-loadbearing components, such as cladding, doors, windows and the like.

Fire safety system

These systems may be active systems, passive systems, or any combination of the two.

Fire-source feature

Used in Deemed-to-Satisfy Provisions to describe a possible fire source external to the building from which a fire could spread to the building. See Figure A1.1(FSF).

A fire-source feature includes the far side of the road, and the side or rear boundary of an allotment. It also includes the far side of lakes, rivers and the like where the construction of buildings is unlikely. These represent the worst-case scenario for the spread of fire from another building. Even if a building on an adjacent allotment is set back from a boundary, the NCC assumes it could be demolished and another building constructed on the boundary.

Note that the term “fire-source feature” does not necessarily apply to a building—it relates to a potential source of fire. That potential may be realised in the future construction of a building. For this reason, the fire-source feature is not simply a line on the ground, nor a point at the top of a building; it is a continuous plane rising above that line or point.

In this sense:

• a line drawn out horizontally from a building to a fire-source feature will hit that feature; and
• form a 90º angle with a line drawn down from the point at which it hits the fire-source feature to the ground, or the top of the adjoining building.

However, some Deemed-to-Satisfy Provisions of the NCC limit the height above a building at which the fire-source feature remains active (see ).

The reason for the exclusion of Class 10 buildings on the same allotment is that they are generally small and have a low fire load.

Fire wall

Fire walls separate fire compartments. To avoid the spread of fire to another part of the building, a fire wall must extend from the fire-rated floor of a storey to the underside of the fire-rated floor above, or to a non-combustible roof covering.

A “fire-resisting” wall is not necessarily a “fire wall”. A fire wall can sometimes be an external wall. See and Figure C2.7(3) of this Guide.

Flammability Index

A test performed in accordance with AS 1530.2 will determine the flammability index of a material.

Flashover

Flashover The term “flashover” is used in of Specification C1.10 dealing with tests for the fire hazard properties of building materials and components. The definition defines the term by specifying the heat release rate in the test. See .

Flight

A flight is the part of a stairway that has a continuous slope created by the nosing line of the stair treads. Quarter landings are not considered part of a flight. However, winders are considered part of a flight. See Figure A1.1(FLI).

Flood hazard level

See Figure A1.1(FLO).

Floor area

When applied to a building or storey, the floor area includes all the space capable of being used. It includes any roofed area, canopy, verandah or covered walkway, etc.

Floor area is used in a number of different contexts in the NCC. It is therefore necessary to define each of these contexts:

• In relation to a building—the sum of the areas of all storeys.
• In relation to a storey—the floor area of the storey includes any enclosing walls. Where there is no enclosing wall in a part of a storey, those areas which may be used for storage, or other purposes, by occupants must be included as appropriate. It therefore includes any roofed area, including a canopy, verandah or covered way if it contributes to the functioning of the building. Internal walls, columns, shafts, stairways, ramps or the like are not deducted. See Figure A1.1(FA)(1).
• In relation to a room—the bounding walls determine the limits of the floor area. Internal walls, columns, stairways, ramps or the like are not deducted. See Figure A1.1(FA)(2).
• In relation to a fire compartment—the fire compartment may not be bounded by walls in all places. If this is the case and a roofed area contributes to the fire load, it should be considered as part of the floor area. See Figure A1.1(FA)(3).
• In relation to an atrium—see Figure A1.1(FA)(4).

Freeboard

See Figure A1.1(FLO).

Functional Statement

Is a term not used within Volume One, however Functional Statements are used in this Guide as an aid to the interpretation of the NCC and not for determining compliance. Functional Statements are statements which describe how buildings and building elements achieve the Objectives.

Glazing

The glazing definition needs to be read in conjunction with the definition of a window and roof light. It can include a glazed door. For the purposes of , the glazing provides an aperture by which light and energy can flow into or from the conditioned space. Glazing includes the glass and any frame system.

Group number

sets out the requirements for Group 1, Group 2, Group 3 and Group 4 materials. A test in accordance with either AS ISO 9239.1 or AS/NZS 3837 determines the group a material belongs to. The NCC permits the installation of Group 1, Group 2 and Group 3 materials. Group 1 materials are the best performing materials. Group 4 materials are the worst performing materials.

Habitable room

Only applies to Class 2 and Class 3 buildings and Class 4 parts of buildings.

Health-care building

The definition of a health-care building means a building whose occupants or patients undergoing medical treatment, need physical assistance to evacuate the building during an emergency and includes a nursing home or similar facility for people who are sick or have a disability and require full-time care. Therefore, a healthcare building could include a residential aged care building in which occupants are provided with some level of medication, and need assistance to evacuate.

Health-care buildings also include day-care surgeries or procedure units. They are distinguished from a doctor’s or dentist’s surgery, because if an evacuation became necessary in these places, patients would probably not need assistance in evacuating.

In a health-care building, patients may be incapable of movement, and require the assistance of another person to evacuate. They might also require medical supervision for a while after treatment.

Health-care buildings are not to be interpreted to include aged care buildings. It should be noted that the NCC contains differing requirements for Class 9a health-care buildings and Class 9c buildings.

House energy rating software

The definition describes the software accredited under the Nationwide House Energy Rating Scheme (NatHERS). NatHERS is the Australian governments' scheme that facilitates consistent energy ratings from software tools which are used to assess the potential thermal efficiency of dwelling envelopes.

Illuminance

Used only in the Performance Requirements of to describe the amount of natural and artificial light required for a building.

Illumination power density

This term is more wide-reaching than the simpler "lamp power density" term also used for the sole-occupancy units of Class 2 buildings and Class 4 parts. It needs to be calculated taking account of the losses from ballast, current regulators and integral control devices associated with the lighting system including track and flexible lighting systems, and fixed lighting that is part of modular furniture and workstation lights. However, socket outlets for intermittent use such as for floor standing lamps, desk lamps, etc. are not included as it is not possible to control them through the building control process. The calculation of illumination power density does not include losses elsewhere in the system, such as in the distribution cabling throughout the building.

Insulation

Insulation is the third criterion used when specifying an FRL.

A building element fails the insulation criterion if the average temperature of the unexposed face of the test specimen rises by more than 140 K (i.e. 140 degrees Kelvin) above the initial temperature. It also fails if the temperature of the unexposed face of the test specimen rises by more than 180 K above the initial temperature.

Integrity

Integrity is the second criterion used when specifying an FRL. See example under “insulation” definition.

The test under AS 1530.4 considers that a building element has failed the integrity criterion when either the element collapses, or the element develops cracks, fissures or other openings through which flames or hot gases can pass.

Internal wall

All walls that are not external walls are internal walls.

Lamp power density

This term was developed in order to simplify the statement of requirements and to simplify checking for sole-occupancy units of Class 2 buildings and Class 4 parts. It relates only to the lamp and does not include the power lost by any ballast, current regulator or control device. However, socket outlets for intermittent use such as for floor standing lamps, desk lamps, etc. are not included as it is not possible to control them through the building control process. The maximum power of a lamp is usually marked on the fitting as the maximum allowable Wattage.

Latent heat gain

This term refers to the heat used to vaporize a liquid without causing a change in temperature, such as heat used to generate steam from heated water at 100°C. Also included, in the NCC context, is the energy in the moisture from the human body.

Light source efficacy

This term is used to describe the effectiveness of a lighting device, and is expressed as the lighting output level in Lux for each unit of electric power consumed, including the power consumed by the lamp. It does not include the power lost by any ballast, current regulator or control gear.

Lightweight construction

The NCC lists building materials of “lightweight construction”. These materials need protection to preserve their integrity from fire and other damage. This is because they are more susceptible to damage than other forms of fire protection. For example, masonry thicker than 70 mm and materials like concrete, which typically do not contain soft materials, are not deemed to be lightweight construction. See and .

Luminance contrast

This term is used in provisions for access for people with a disability. Luminance contrast is the measurement of the amount of light reflected from one surface or component, compared to the amount of light reflected from the background or surrounding surfaces. The majority of people who are blind or vision impaired have some vision. The provision of sufficient luminance contrast between components or surfaces and their backgrounds assists in their identification and use.

Massive timber

This term refers to chemically bonded composite timber elements, such as cross laminated timber (CLT), laminated veneer lumber (LVL) and glulam, which are at least 75 mm thick as measured in each direction. contains requirements for when massive timber is used as fire-protected timber.

Mezzanine

A “mezzanine” must be part of a room. If an intermediate floor is enclosed by a wall it is no longer within another room, and is therefore no longer a mezzanine. Such rooms are sometimes called “mezzanines” by the layperson. This does not mean they are classified as such by the NCC. See Figure A1.1(ME).

Non-illuminated exit sign

This definition allows exemptions to specific Deemed-to-Satisfy Provisions of for farm buildings, so that exit signs which are not illuminated can instead be provided in certain scenarios.

Objective

Is a term not used within Volume One, however Objectives are used in this Guide as an aid to the interpretation of the NCC and not for determining compliance. An Objective means a statement which is considered to reflect community expectations.

Open-deck carpark

The Deemed-to-Satisfy Provisions contain a number of concessions for open-deck carparks. The concessions are based on the amount of natural ventilation available. Ventilation is needed for the dissipation of car fumes and also for heat and smoke during a fire. An open-deck carpark may be a whole, or part, of a building.

Open space

Egress from a building must be to a road or open space. An open space must be open to the sky and connect directly to a public road. See .

The NCC uses the term "road" and "public road" as the case requires. A "road" can be a private or public road. The appropriateness of a type of road for the purposes of the NCC is dependant on rights of access to the road. A "public road", as the name suggests, is a road available for use by the public and is usually controlled and maintained by or on behalf of a government body. As a consequence, a public road is considered to be a more permanent feature when compared to other types of road such as a private road.

Open spectator stand

Traditionally called a “grandstand”. The Deemed-to-Satisfy Provisions contain a number of concessions for open spectator stands. Concessions are based on the amount of natural ventilation, at the front of these stands, during a fire. They may be a whole, or part, of a building.

Other property

Used to describe nearby buildings and land requiring protection for structural, fire or drainage reasons. The purpose of including a road as part of “other property” is that in certain parts of the NCC, a road, or the people using it, may need protection.

Outside air economy cycle

This term describes a mode of operation of an air-conditioning system in which the quantity of outside air is increased beyond that needed by the mechanical ventilation requirements of in order to provide free cooling. Free cooling can be initiated when cooling is required by the air-conditioning system and the outside air temperature is below the set-point temperature of the conditioned space.

Panel wall

The difference between a panel wall and a curtain wall is that a panel wall is supported at each storey, and a curtain wall is not.

Patient-care area

Includes “ward areas” and “treatment areas”.

Performance Requirement

See Part .

Performance Solution

See Part .

Personal care service

Personal care services include any combination of the listed services. The definition is used in defining an aged care building. (See comments on the definition of aged care building).

Piping

This term may have a different meaning in other parts of the NCC or in NCC referenced documents, for example, in relation to sprinklers. This definition of piping is only applicable to where it is used mainly for thermal insulation provisions.

Pressure vessel

This term refers to enclosed vessels subjected to internal or external pressure. Gas cylinders are an example of a pressure vessel, however gas cylinders installed in small appliances are not intended to be captured. The term also does not apply to boilers, storage tanks intended for storing liquids where the pressure at the top of the tank is not more than 1.4 kPa above or 0.06 kPa below atmospheric pressure, domestic hot water heaters and pressure vessels associated with fire suppression systems.

Primary building element

Those materials and constructions subject to attack by termites causing structural problems. This includes stairs and ramps. Excluded are building elements which provide bracing to a wall, but this is not designed as part of their function. An example would be plasterboard not required for bracing or an external cladding.

Private bushfire shelter

The term is used to describe a Class 10c building. The provisions for Class 10c private bushfire shelters are contained in the Housing Provisions (Volume Two) of the NCC.

Private garage

To be classified as a private garage (and therefore a Class 10a building or part), a structure can only contain a maximum of three vehicle spaces, unless the garage is associated with a Class 1 building.

A building designed to accommodate three-or-less vehicle spaces carries a comparatively low fire load, even if used commercially. Thus, there is not much difference between the fire risk from a domestic private garage and one used commercially.

If a garage is not associated with a Class 1 building, and contains more than three vehicle spaces, it is a carpark and therefore a Class 7 building or part.

Product Technical Statement

A Product Technical Statement is a form of documentary evidence that states that a building material, product, form of construction or design (subject to any specified conditions or limitations) complies with relevant requirements of the NCC.

Professional engineer

Includes a professional engineer eligible for registration with the Institution of Engineers (Australia) under classification NPER3. Some States and Territories define “professional engineer” differently. Such definitions override the NCC definition.

Public corridor

Not all corridors and hallways are public corridors. A public corridor must be enclosed and provide egress from more than one sole-occupancy unit. Examples include passages leading from hotel suites, lift lobbies and foyers in high-rise buildings. Public corridors can be required to provide egress to a required exit.

Pump power

The pump power is the amount of power that a pump needs and includes the inefficiency of the pump and the power consumed by any drive train. This means that it is the power a pump motor needs to provide either directly or by an output shaft. It does not include any motor losses, which are usually covered by Minimum Energy Performance Standards (MEPS), nor does it include any control gear such as Variable Speed Drive (VSD). Figure A1.1(PP) describes pump power.

R-Value

The R-Value of a component relates to the component material itself, and does not include any surface coatings, air gaps or surface resistances. Except for ductwork, piping, heat exchanger and tank insulation, R-Values are rarely used independently, but can be used to express a component’s contribution to an insulating system, in which case, the thermal resistance expression for the system would become Total R-Value.

Reference building

A reference building is used to determine the maximum annual energy consumption allowed. This is done by applying the Deemed-to-Satisfy Provisions, along with certain stated criteria, to a proposed design. The annual energy consumption calculated is then used to assess the energy efficiency of the Performance Solution.

Reflective insulation

This term is used in AS/NZS 4859.1 and covers a range of insulating products that have one or more reflective surfaces. Reflective insulation is one example of sarking-type material.

Renewable energy

The definition of renewable energy clarifies what are the sources of operational energy that do not result in significant greenhouse gas emissions. Examples given include solar, wind, hydro-electric, wave action and geothermal. For the purpose of the defined term, an on-site renewable energy source does not include GreenPower.

Required

When used in the Performance Requirements, the term means required to meet the Performance Requirement. When used in the Deemed-to-Satisfy Provisions, it means required to meet those provisions.

Residential aged-care building

Applies only to buildings housing residents with mental or physical impairments caused by the ageing process. Such impairments require that patients need assistance in their daily lives.

People are employed to assist and care for these residents. Hence, the building requirements aim to provide a more amenable environment for the residents.

The definition applies to Class 3 and Class 9a buildings. The NCC contains a number of concessions for Class 3 residential aged-care buildings. See and .

Resident use area

Only applies to Class 9c buildings.

Resistance to the incipient spread of fire

Refers to the ability of a ceiling to prevent the spread of fire and thermally insulate the space between the ceiling and the roof, or floor above. “Resistance to the incipient spread of fire” is superior to “fire-resistance” because it requires a higher standard of heat insulation. Refer to <std.xref>AS 1530.4</std.xref>.

Rise in storeys

describes how to calculate the rise in storeys.

Roof light

The definition provides a distinction between a window and a roof light based on its angle to the horizontal.

Safe place

A safe place provides a final refuge from a fire, such as a road or open space at the end of an exit. It can also be a temporary “haven” or “refuge” to protect people while they are evacuating during a fire. The term is only used in the Performance Requirements. Safe places can be inside or outside a building, and must provide a person with protection from a fire and then allow them to safely escape to a road or open space.

Sanitary compartment

The term refers to a room or space which contains a closet pan or urinal. This can include rooms such as a water closet, a bathroom, a shower room or the like which also contains a closet pan or a urinal. The term additionally refers to a 'space' which may contain a closet pan or urinal. An example would be a bank of toilets where each individual cubicle is considered a sanitary compartment. Figure A1.1(SC) provides differing configurations of sanitary compartments.

Sarking-type material

A sarking-type material is a flexible membrane that may be used for waterproofing, vapour proofing or thermal reflectance and includes reflective insulation. Commonly used terms include sarking, reflective foil, building wrap and breathable membrane.

Self-closing

Applies to doors which are smoke or fire doors and the like. In each case it is important that the doors be fitted with a device that immediately closes them after manual opening, and keeps them closed to stop the spread of fire and/or smoke during a fire situation.

Sensible heat gain

This term refers to the heat added to air to cause its temperature to rise. This can be heat from people, other than latent heat, and the heat from lights or appliances, other than the latent heat from steam generating devices.

Service

There are many services in a building, but for NCC purposes, only certain building services are regulated, and this excludes process services. Those services regulated are stated in the definition and specified in the Deemed-to-Satisfy Provisions.

Service station

An outlet which sells petrol and has an area for servicing motor vehicles. The whole service station can be classified as a Class 6 building. The definition also applies to a car dealership which contains an area for the servicing of vehicles.

Shaft

The definition includes the top and bottom as well as the walls.

Smoke-and-heat vent

Can be automatically opened as necessary, or permanently fixed open. See Parts and .

Smoke-Developed Index

A test in accordance with AS/NZS 1530.3 determines the Smoke-Developed Index of a material. The index is based on a logarithmic scale of 0 to 10. A lower index number indicates better performance.

Smoke development rate

A test in accordance with AS ISO 9239.1 determines the smoke development rate of a material. A lower value indicates better performance.

Smoke growth rate index

A test in accordance with AS ISO 9705 determines the smoke growth rate index (SMOGRA_RC) of a material. A lower value indicates better performance.

Sole-occupancy unit

A sole-occupancy unit is an area within a building for the exclusive use of the owner or occupier. It is irrelevant if the area is occupied by an individual, a number of people, or by a company. Exclusivity of use is the key factor in determining whether an area or room is a sole-occupancy unit.

Spread-of-Flame Index

A test in accordance with AS/NZS 1530.3 determines the Spread-of-Flame Index of a material. The index is based on a logarithmic scale of 0 to 10. A lower index number indicates better performance.

Standard Fire Test

AS 1530.4 contains details of the Standard Fire Test. The test is used to determine the FRL of a building element. The results are recorded in order as: structural adequacy, integrity and insulation.

Storey

illustrates that a storey extends from the floor level of the subject area to the floor level above, or, if the storey is at the top of the building, to the ceiling or roof. It is not unusual for people to simply regard the ceiling or the bottom of the storey above as the top of a storey.

The listed exceptions for a storey are normally small areas with a low fire load and low occupation.

Structural adequacy

Structural adequacy is the first criterion used when specifying an FRL. It is used only in relation to the FRL of a building element. See the example under ‘insulation’ definition.

Swimming pool

Applies to swimming and wading pools, and spas (excluding units such as spa baths emptied after each use). For provisions see . These provisions do not apply to all swimming pools.

Total R-Value

The definition of the Total R-Value of a thermal insulating system covers the various materials themselves and any surface coatings, air gaps or surface film resistances. As a minimum, a system must consist of a material plus two surface films, usually an outer film exposed to a wind velocity and an inner film exposed to a lower velocity. A brick veneer wall, for example, has at least five components, i.e. the outer air film, the brickwork, an air gap across the cavity, plaster lining and an inner air film. Bulk insulation in the frame cavity may be another component, while reflective insulation provides a reflective surface as well as one more air gap.

Total System Solar Heat Gain Coefficient (SHGC)

The definition of Total System Solar Heat Gain Coefficient (SHGC) has been developed to reflect the specific context in which this term is used in the NCC, and is calculated using the Technical Protocol and Procedures Manual for the Energy Rating of the Fenestration Products by the Australian Fenestration Rating Council (AFRC).

Total System U-Value

U-Value is a measure of the rate of heat transfer through a material and is the reciprocal of R-Value. Total System U-Value is the reciprocal of the sum of the R-Values of individual elements. Although it applies to all materials, U-Values are generally stated for transparent and translucent materials while R-Values are generally stated for opaque materials. Transmittance is referred to for transparent and translucent materials while overall heat transfer coefficient is the general term. Total System U-Value is used in the NCC for roof lights and glazing and is calculated using the Technical Protocol and Procedures Manual for the Energy Rating of the Fenestration Products by the Australian Fenestration Rating Council (AFRC).

Treatment area

Part of a “patient-care area”. In a treatment area, a patient undergoes treatment (e.g. an operation), which may result in the patient being unable to evacuate without assistance in an emergency such as a fire.

Unique wall

Used only in Verification Method and is intended to capture walls which are neither cavity walls or use direct fixed cladding. This includes, but is not limited to, single skin walls which provide not only the outer weather protection but also act as the internal wall and may provide structural components. An example of such walls would be a concrete tilt up panel, single skin masonry or a glass curtain wall.

A unique wall is illustrated in Figure A1.1(UW).

Verification Method

See Part .

Ward area

Part of a “patient-care area”. It includes a hospital or nursing-home ward and the nursing stations associated with such wards. Also, any associated living areas, such as bath and shower rooms, toilets, TV rooms, activity rooms and the like.

Window

A window must be capable of allowing light into a building, even when closed. Any transparent or translucent glass pane, brick or block, or a roof light or the like, is a window.

only applies to the Deemed-to-Satisfy Provisions of the NCC.

means that contractual matters or clauses defining responsibilities of various parties, and matters in Australian Standards or other codes not appropriate for adoption in the NCC are not included when a standard is called up in a Deemed-to-Satisfy Provision.

is only mandatory to Deemed-to-Satisfy Provisions. However, referenced documents are only applicable to the NCC provision that references the document.

A building proponent undertaking a Performance Solution can use any element or edition of any document, if they help satisfy the Performance Requirements. They do not need to use the documents listed in .

lists the specific edition of the Standard or other document adopted, including any amendments considered appropriate for the Deemed-to-Satisfy Provisions. Other editions of (or amendments to) the referenced document are not adopted, and have no standing under the NCC.

When a document listed in refers to a second document, that reference is that reference is to the second document as it existed at the time of publication of the document listed in .

sets out the general rules that any referenced document must adhere to. identifies the applicable edition of the NCC referenced document as well as the relationship of any secondary references.

The following is the precedence, or pecking order, for documents used in the building regulatory system. Any State or Territory Act or regulation which adopts the NCC takes precedence over any NCC provision. The NCC, in turn, takes precedence over any referenced document.

All the provisions that apply to a particular building must be satisfied. Relevant exemptions and limitations are noted within the NCC provisions. See .

State and Territory variations and additions are part of the NCC and are included as an Appendix to NCC Volume One.

When the NCC refers to a building, that reference can be to the whole building or any part of the building. Whether this provision applies depends on the circumstances of that case and the circumstances in which the reference is made.

Generally, a reference to a building is a reference to the whole building, regardless of classification. However, when a provision is applicable to a specific class or classes of building, that reference to a building may be a reference to the whole building or part of the building depending on how the building is classified.

For example, where a building has a single classification, a reference to a building in the NCC is understandably a reference to a whole building. However, where a building has parts of different classification, unless the contrary intention appears (i.e. there is a specific reference to the whole building), a reference to a building in the NCC is a reference to the relevant part of the building. This means that each part of the building must comply with the relevant provisions for its classification.

A number of the Performance Requirements of the NCC use the expression “to the degree necessary”. This expression provides flexibility by allowing appropriate authorities to determine the degree of compliance necessary in a particular case.

For example, an appropriate authority might judge that an item need not be installed, or a particular level of performance be achieved. The expression is often supported by examples in this Guide.

Under and Classes 1a and 1b, 7a and 7b, 9a, 9b and 9c, and 10a, 10b and 10c are separate classifications, and if joined together or in close proximity may require fire separation in certain situations. In the NCC, when the designation 'a', 'b' or 'c' is not applied, the reference is to all buildings of the general class. For example, 'Class 9b' refers only to Class 9b buildings, but 'Class 9' refers to Class 9a, Class 9b and Class 9c buildings.

Explanatory information is provided within Volume One under certain Deemed-to-Satisfy Provisions to identify cross-volume considerations within Parts of NCC Volume Three – the Plumbing Code of Australia (PCA).