NCC Tutor lesson - Using NCC Volume One

Slide 1:

Welcome to using NCC Volume One.

Slide 2:

The focus of this presentation is on how to use NCC Volume One, to find and interpret information about Performance Requirements and compliance solutions for Class 2-9 buildings, and some Class 1 and Class 10 buildings/structures.

Slide 3:

What you will learn? What NCC Volume One contains? Where to get guidance on using Volume One? How NCC Volume One is organised and where to find information within it? Key Concepts in Volume One. How to interpret the different sections of Volume One.

Slide 4:

What does Volume One of the NCC contain? The focus in NCC Volume One is on requirements for multi-residential, commercial, industrial, and public/institutional buildings. The provisions within NCC Volume One that apply to Class 1 and 10 buildings generally relate to access for people with a disability.

NCC Volume One is sometimes referred to as the ‘BCA Volume One’. NCC Volume Two is often referred to as ‘BCA Volume Two’ or the ‘Housing Provisions’.  NCC Volume Three is often referred to as the ‘Plumbing Code of Australia’ or ‘PCA’.

Slide 5:

Where can we get guidance on Volume One? All of the resources shown on the slide are non-mandatory. In other words, they do not contain any provisions that must be complied with. They contain only explanatory and guidance information. All the mandatory provisions are in NCC Volume One. The Guide to NCC Volume One is integrated with the online NCC Volume One.  The various handbooks are developed, updated, and issued separately from the NCC Volumes.  They are also available on the ABCB website.

Slide 6:

How is Volume One of the NCC organised? Section A contains the Governing Requirements, which are the same in all volumes of the NCC. This includes information on building classifications and referenced documents.

As the Governing Requirements is the same across all volumes of the NCC, it will not be discussed further in this module. It is discussed in the Understanding the NCC module.

Sections B-J contain all the Performance Requirements, Verification Methods and DTS Provisions for Volume One, that is all those applicable to Class 2-9 buildings (and some Class 1b, and Class 10 buildings/structures). This includes Performance Requirements, Verification Methods and DTS Provisions for building structure, health, independence, comfort and wellbeing (amenity), safety, including fire safety, access and safe movement, a building’s energy efficiency, a range of other aspects and special building types.

DTS Provisions for Volume One often include Specifications which provide detailed requirements for using some DTS Provisions. They must be complied with when developing a DTS Solution. 

The structure of Volume One is similar to the structure of Volume Three, with the Performance Requirements, Verification Methods and DTS Provisions grouped across different sections. This is different from Volume Two, where Performance Requirements and Verification Methods are all gathered together in Volume Two, with the DTS Provisions located in a separate ABCB Housing Provisions Standard. 

Volume One contains the same Schedules as the other volumes. Most of the text in the Schedules is identical across the volumes, but the contents of Schedule 4 to 11 State and Territory Appendices varies. 

As the Schedules are more or less the same across all volumes of the NCC, they will not be discussed further in this module. (They are discussed in the Understanding the NCC module). So, this module focuses on understanding and using Sections B-J of Volume One of the NCC.

Slide 7:

Key concept, Rise in Storeys. In NCC Volume One, the rise in storeys of a building generally means the number of storeys above natural ground level, and any storeys within the roof space.

The rise in storeys has an impact on a building’s risk of exposure to radiant heat from a fire in another building, emitting radiant heat to another building. This might cause damage to the other building or cause it to also catch on fire, occupants, who may need to travel down a stairway to safely evacuate the building.

A building’s rise in storeys is referenced in Sections C, D, E and G of NCC Volume One, and can determine which particular provisions might apply to a building. For example, It is central to identifying which rules apply when ensuring that a building can resist fire appropriately.

A number of concessions around fire resistance provisions depend in part on the building’s rise in storeys. This means that some provisions may not apply to a building below a certain rise in storeys, provided other conditions are met. (e.g. C4D8 (Protection of doorways in horizontal exits), C4D11 (Openings in fire-isolated lift shafts)). The number and location of fire exits in Class 9b buildings can depend in part on each building’s rise in storeys. (E.g. D2D3(4)).

The rise in storeys of a building is used to determine the type of construction (along with the building’s classification), which is the next term to be defined.

Slide 8:

Calculating the rise in storeys. What is the rise in storeys of the building shown in this image? The rise in storeys equals  7. Underground floors don’t count in the calculation, since they are completely below natural ground level.

Slide 9:

Calculating the rise in storeys. What difference does a firewall make to the calculation of the rise in storeys for this multi-unit development?

Without the firewall, the rise in storeys is 4 for the entire development. In other words, the 2-storey section must also be built to meet the fire protection provisions that apply to the 4-storey section.

With the firewall, the rise in storeys is 4 for the left section and 2 for the right section. So, the provisions that would apply to each section are potentially different. (This doesn’t mean that the builder would automatically build the 2 sections to different standards.)

Slide 10:

Key concept. Type of construction. The type of construction required for a building depends on a combination of the building classification and the rise in storeys, which they looked at on the last slide.

These 2 factors determine the risk to the building, other buildings and occupants from fire. For example, the building classification points to a building’s likely use, fire load, population and the mobility of its occupants, e.g. whether they are likely to be sleeping or alert.

The height of the building determines the likely evacuation times and difficulty. Thus, these 2 factors are used to determine the minimum type of fire-resisting construction required for Class 2-9 buildings.

The exact requirements for each type of construction are contained in Specification 5 in Volume One. Some other factors will also determine fire resistance construction requirements, such as the size of individual fire compartments or atriums in a building.

There are special rules for some configurations of some building classifications, e.g. buildings with multiple classifications (C2D4), 2 storey Class 2, 3 or 9c buildings (C2D6), Class 4 parts of buildings (C2D7).

Some buildings can have more than one type of construction. The requirements in Table C2D2 are DTS Provisions, and a designer/builder always has the option of developing a Performance Solution to meet the Performance Requirements.

Slide 11:

What type of construction is required for each of these buildings? Class 3 building with 2 storeys is Type B construction. Class 7 building with 4 storeys is Type A construction. Class 9 building with 3 storeys is Type A construction. Class 5 building with one storey is Type C construction.

Slide 12:

Which type of construction is the most fire-resistant? Type A construction, Type B construction, Type C construction. They are all equally resistant to fire. The correct answer is Type A construction. Buildings that comply with Type A construction requirements have the greatest fire resistance.

Slide 13:

Key concept. Fire compartments. The maximum floor area of fire compartments required for a building depends on a combination of the building classification and the type of construction, which they looked at on the last slide. The requirements in Table C3D3 are DTS Provisions, and a designer/builder always has the option of developing a Performance Solution to meet the Performance Requirements.

Alternatively, a designer/builder can choose to use a different type of construction, which would change the requirements for fire compartmentation. For example, a building may only be required to be built using Type C construction. If this would result in a space/s (fire compartments) that are too small to be practical for the purpose of the building, then the building designer could use a more fire-resistant type of construction, i.e. Type B or Type A. This would then allow design and building of larger spaces, while still complying with Performance Requirements. There are special rules for large, isolated buildings of Class 5-9 (C3D4).

Slide 14:

What is the maximum floor area for a fire compartment in these buildings? These answers are Class 8 building, Type B construction, Max floor area = 3 500 m² ,Max volume = 21 000 m³

Class 7 building, Type C construction, Max floor area = 2 000 m² ,Max volume = 12 000 m³

Class 9b building, Type C construction, Max floor area = 3 000 m² ,Max volume = 18 000 m³

Class 9a building, Type A construction, Max floor area =5 000 m² ,Max volume = 30 000 m³

Slide 15:

What do sections B – J contain?  While the different sections provide Performance Requirements, Verification Methods and DTS Provisions for specific design and building areas, they must be applied holistically. That is, you need to consider the impact of a decision in one area on requirements in other areas.

Example of holistic application. Formulating a Performance Solution to increase the prescribed distance of travel to an exit (Section D Access and egress) may affect the coverage requirements for fire fighting equipment (Section E Services and equipment). Section B contains structural provisions that apply to all classes of buildings.

Sections C-J specify provisions that generally apply to particular classes and types of buildings. However, these provisions don’t necessarily apply to all buildings of a particular classification. They are sometimes limited to buildings that meet other criteria as well, such as building height, floor area, number of people the building will accommodate, the layout of the building.

Sections in Volume One are organised in different ways. There are 2 main variants in the organisation. Some sections list all the relevant Performance Requirements first, then list all the Verification Methods, then give all the DTS Provisions, including  Specifications where relevant. Other sections are divided into Parts, which cover a particular topic, and each Part then contains the applicable Performance Requirements, Verification Methods and DTS Provisions. Check each section to make sure you understand how it is organised.

Slide 16:

Example, Section E Services and equipment.

Question 1:  What criterion usually determines when a building of any class needs to have fire sprinklers? Possible Answer 1: One trigger for when a building is required to have fire sprinklers installed is when the building has an effective height of more than 25 m. Effective height means that any part of the building is above this height.  However, subsequent clauses including E1D6 to E1D13 may also have other triggers for fire sprinklers, additional requirements or exclusions.

Question 2:  When does a Class 2 or 3 building – excluding a residential care building – require fire sprinklers? Possible Answer 2:  A Class 2 or 3 building – excluding a residential care building – requires fire sprinklers if any part of the building has a rise in storeys of more than 4, even if the effective height is less than 25 m. If the building has an effective height of more than 25 m, sprinklers are also needed.

Question 3: When does a Class 3 building used as a residential care building require fire sprinklers? Possible Answer 3: A Class 3 building used as a residential care building requires fire sprinklers throughout the building and in any fire compartment that is used for residential care, regardless of the effective height of the building or any other factors. Note there is a variation to this clause for Victoria. 

Slide 17:

Example: Section F Health and amenity 

Question 1:  What is the difference in the minimum required height of a kitchen and another habitable room that is not a kitchen? Possible Answer 1: The minimum height of a kitchen is 2.1 metres while the minimum height of a habitable room that is not a kitchen is 2.4 metres. So, the difference is 0.3 of a metre.

Question 2: What minimum height applies to a habitable attic space with a sloped ceiling? Possible Answer 2:  A habitable attic space must have a minimum height of 2.2m for not less than two-thirds of the floor area of the room or space.

Slide 18:

Match the Section with its subject. Section C equals fire resistance. Section E equals services and equipment. Section I equals special use buildings. Section J equals energy efficiency.

Slide 19:

Interpreting Sections B- J of Volume One. 

Question 1: In Section C Fire resistance, what factors determine the required minimum type of construction? Part C2D2 Type of construction required. Table C2D2 Type of construction required. Type of construction depends on the building classification and rise in storeys.

Question 2: In Section D, where can we find specific reference to access and egress provisions for people with a disability? Performance Requirements = D1P1 Access for people with a disability.  Deemed-to-Satisfy Provisions = Part D4 Access for people with a disability.

Question 3: Section I of Volume One contains DTS Provisions for special-use buildings. Where can we find the Performance Requirements for these buildings? In Sections B-J of Volume One. (Note Section H is in NCC Volume Two).

Question 4: According to Section C Fire resistance, when is a below-ground storey included in the calculation of a building’s rise in storeys? Part C2D3 Calculation of rise in storeys. Guide to NCC Volume One, Part C2D3 Calculation of rise in storeys. When more than 1 metre of that storey is above natural ground level.

Question 5: According to the DTS Provisions in Section E, what smoke hazard management devices must be installed in a Class 2 building that is more than 25 m in effective height? Part E2 Smoke hazard management. E2D5 Buildings more than 25 m in effective height: Class 2 and 3 buildings and Class 4 part of a building. A Class 2 building that is more than 25 m in effective height must be provided with an automatic smoke detection and alarm system that complies with Specification 20.

E2D13 Basements (other than Class 7a buildings), similar requirements for basements as per E2D5. E2D21 Provisions for special hazards.  Additional smoke hazard measures may be required if the building has special characteristics, functions, materials or mix of building classifications that make the building different from other buildings. The relevant authorities will advise on whether this provision will be applied to a building. 

Question 6: According to Part D3 Construction of exits, when/where must barriers be installed to prevent falls? D3D17 Barriers to prevent falls. If the trafficable surface is 1m or more above the surface beneath, continuous barriers must be provided along the side of a roof which building users can access , a stairway or ramp, a floor, corridor, hallway, balcony, deck, veranda, mezzanine, access bridge or the like, any delineated path of access to a building.

Slide 20:

How do we use Volume One? 1. Identify the building’s classification, rise in storeys and required type of construction. 2. Identify the applicable Performance Requirements, Verification Methods and DTS Provisions in Sections B-J. 3. Check definitions and note exceptions, limitations and state/territory variations to any Performance Requirements, Verification Methods or DTS Provisions. 4. Decide on use of a DTS Solution, Performance Solution or a combination of both.

Slide 21:

Match the Section with its subject. Section B equals structure. Section D equals access and egress. Section F equals health and amenity. Section G equals ancillary provisions.

Slide 22:

What type of construction is required? The diagram shows a 3 storey building with different uses intended for each storey, and therefore a different building classification for each storey.

What type of construction must be used for this building, and why? In a building with multiple classifications, the type of construction applicable to the top storey applies to all the storeys below it (this does not apply if the top floor is a Class 4 part of a building).

The top storey is Class 2, therefore this class applies to the whole building for the purposes of determining the required type of construction.

The rise in storeys is 3, so the building therefore must be of at least Type A construction. (Refer to Table C2D2).
Slide 23:

What type of construction is required? The diagram shows the same 3 storey building, but the intention is to build a Class 4 part of a building on the top storey.

What type of construction must be used for this building, and why? For the purposes of determining the type of construction, when the whole of the top storey of a multi-storey building is a Class 4 part of a building, the class of the next highest storey applies to the top storey.

The building therefore must be at least Type B construction. (Refer to Table C2D2).

If the Class 4 part of a building was only a portion of the top storey, then the type of construction would be determined by the class of the other part of the top storey.

Slide 24:

Application of Section B. What building classifications do the structural provisions in Section B apply to? The structural provisions in Section B apply to all Class 2-9 buildings.

Other Sections of Volume One contain provisions that might apply to one or more classes of buildings and may have limitations in their application, based on things like the building height, rise in storeys etc.

Slide 25:

True or false? You must refer to the Guide to Volume One when identifying requirements for 
Class 2-9 buildings.

If you answered False, yes that’s right. The Guide to Volume One contains useful information and explanations, but NOT the mandatory requirements.

Slide 26:

Summary. Section A: Governing Requirements. Exactly the same as other volumes

Sections B-J. Performance Requirements. Verification Methods. Deemed-to-Satisfy Provisions, including Specifications.

Schedules. Exactly the same as other volumes.

Slide 27:

Key points. Section B Structural provisions apply to all building classes. Sections C-J provisions generally apply to particular classes and types of buildings, but may have limitations. Section H is in Volume Two.

Key concepts in Volume One. Rise in storeys. Type of construction. Fire compartments. Different sections are organised in different ways. May have Parts which group Performance Requirements, Verification Methods and DTS Provisions under topic areas

The following documents on the ABCB website provide additional, non-mandatory guidance: Guide to NCC Volume One. Other handbooks on specific topics

Slide 28:

Thank you for your time. That brings our presentation on Using NCC Volume One to a close. If you’d like more information, please visit abcb.gov.au