NCC 2022 Volume Two - Building Code of Australia Class 1 and 10 buildings

H4

Part H4 Health and amenity

Part H4 Health and amenity

Introduction to this Part

This Part is intended to address several factors which impact on health and amenity. These factors include, waterproofing of wet areas, room heights, kitchen, laundry and toilet facilities, lighting, ventilation, sound insulation and condensation.

Objectives

The Objective is to safeguard the occupants from illness or injury and protect the building from damage caused by the accumulation of internal moisture arising from the use of wet areas in a building.

The Objective is to safeguard the occupants from injury or loss of amenity caused by inadequate height of a room or space.

The Objective is to—

  1. safeguard occupants from illness caused by infection; and
  2. safeguard occupants from loss of amenity arising from the absence of adequate personal hygiene facilities; and
  3. enable occupants to carry out laundering; and
  4. provide for facilities to enable food preparation; and
  5. enable unconscious occupants of sanitary compartments to be removed from the compartment.

The Objective is to safeguard occupants from injury, illness or loss of amenity due to—

  1. isolation from natural light; and
  2. lack of adequate artificial lighting.

The Objective is to safeguard occupants from illness or loss of amenity due to lack of air freshness.

The Objective is to safeguard occupants from illness or loss of amenity as a result of undue sound being transmitted between adjoining dwellings.

The Objective is to reduce the likelihood of condensation or water vapour build-up causing illness, injury or loss of amenity for building occupants.

Applications

H4O7 only applies to a Class 1 building.

Functional Statements

A building is to be constructed to avoid the likelihood of—

  1. the creation of any unhealthy or dangerous conditions; or
  2. damage to building elements,

caused by dampness or water overflow from bathrooms, laundries and the like.

A building is to be constructed to provide height in a room or space suitable for the intended use.

A building is to be provided with suitable—

  1. space and facilities for personal hygiene; and
  2. space or facilities for laundering; and
  3. space and facilities for the preparation and cooking of food; and
  4. space or other means to permit an unconscious occupant to be removed from a sanitary compartment; and
  5. means for the sanitary disposal of waste water.

Applications

H4F3 only applies to a Class 1 building.

(1) A habitable room within a building is to be provided with openings to admit adequate natural light consistent with its function or use.

(2) A space within a building used by occupants is to be provided with artificial lighting consistent with its function or use which, when activated in the absence of suitable natural light, will enable safe movement.

A space used by occupants within a building is to be provided with adequate ventilation consistent with its function or use.

A building element which separates dwellings is to be constructed to prevent undue sound transmission between those dwellings.

Building elements in areas subject to water vapour or condensation must be constructed to reduce risks to the health of building occupants.

Applications

H4F7 only applies to a Class 1 building.

Performance Requirements

(1) To protect the structure of the building and to maintain the amenity of the occupants, water must be prevented from penetrating—

  1. behind fittings and linings; or
  2. into concealed spaces,

of sanitary facilities, bathrooms, laundries and the like.

SA H4P1 Wet areas2019: P2.4.1

Insert SA subclause H4P1(2) in clause H4P1 as follows:

(2) Floors in bathrooms, or rooms containing a shower or sanitary fixture, must be installed in a manner that will prevent accumulation of water on the surface which could create unhealthy or hazardous conditions.

A room or space must be of a height that does not unduly interfere with its intended function.

(1) Suitable sanitary facilities for personal hygiene must be provided in a convenient location within or associated with a building, appropriate to its function or use.

(2) Laundering facilities or space for laundering facilities and the means for sanitary disposal of waste water must be provided in a convenient location within or associated with a building, appropriate to its function or use.

(3) A food preparation facility must be provided which includes—

  1. a means for food rinsing, utensil washing and the sanitary disposal of associated waste water; and
  2. a means for cooking food; and
  3. a space for food preparation.

(4) A sanitary compartment must be constructed with sufficient space or other means to enable an unconscious occupant to be removed from the compartment.

Applications

H4P3 only applies to a Class 1 building.

Explanatory information

For the purposes of H4P3(2), waste water includes water soiled as a result of clothes washing, mopping floors and other domestic cleaning processes.

(1) A habitable room must be provided with windows, where appropriate to the function or use of that part of the building, so that natural light, when available, provides an average daylight factor of not less than 2%.

(2) Artificial lighting must be installed to provide an illuminance of not less than 20 lux appropriate to the function or use of the building to enable safe movement by occupants.

Applications

H4P4(2) only applies—

  1. to sanitary compartments, bathrooms, shower rooms, airlocks, laundries and the like; and
  2. if natural light of a suitable standard is not available.

Explanatory information

H4P4(1) nominates a minimum average daylight factor for rooms provided with natural light. Note that H4V2 provides a method by which average daylight factor may be calculated.

To comply with H4P4(2), the level of artificial light must enable safe movement by occupants, appropriate to the use of the building. For example, in a movie room a lower level of lighting may be appropriate while a movie is being screened, however at the beginning and end of the movie when occupants are entering and exiting the movie room the minimum lighting level of 20 lux may be appropriate.

(1) A space within a building used by occupants must be provided with means of ventilation with outdoor air which will maintain adequate air quality.

(2) A mechanical air-handling system installed in a building must control—

  1. the circulation of objectionable odours; and
  2. the accumulation of harmful contamination by micro-organisms, pathogens and toxins.

(3) Contaminated air must be disposed of in a manner which does not unduly create a nuisance or hazard to people in the building or other property.

NCC Blurbs

(1) Walls separating dwellings must provide insulation against the transmission of airborne and impact generated sound sufficient to prevent illness or loss of amenity to the occupants.

(2) The required sound insulation of walls must not be compromised by the incorporation or penetration of a pipe or other service element.

NCC Title

Sound insulation

NCC State
NT
NCC Variation Type
Replacement
NCC SPTC Current
Sound insulation

(1) Walls separating dwellings must, to provide insulation against the transmission of airborne sound, have a weighted standardised level difference with spectrum adaptation term (DnT,w+Ctr) not less than 45.

(2) Walls separating a bathroom, sanitary compartment, laundry or kitchen in a dwelling from a habitable room (other than a kitchen) in an adjoining dwelling, must provide insulation against impact generated sound sufficient to prevent illness or loss of amenity to the occupants.

(3) The required sound insulation of walls must not be compromised by the incorporation or penetration of a pipe or other service element.

Risks associated with water vapour and condensation must be managed to minimise their impact on the health of occupants.

Applications

H4P7 only applies to a Class 1 building.

Verification Methods

(1) Compliance with H4P2 is verified where the height of a room or space provides an appropriate activity support level that does not unduly interfere with its intended function.

(2) For a room or space in (1), the activity support level must consider the dimensions of—

  1. doors, ramps, barriers, stairs and windows; and
  2. fixed fittings and domestic services; and
  3. fixed and moveable equipment or furniture; and
  4. occupant circulation spaces.

Explanatory information

The intent of H4P2 is the height of a room or space is sufficient for the intended use of the room or space. ‘Intended use’ recognises that the height required in a room or space is directly related to the room or space's intended function.

H4V1 is a means to verify that the height of a room or space is suitable for the intended use, and therefore meets the requirement of H4P2.

In relation to the intended function of a room or space, the activities that are likely to be undertaken by occupants in the room of space, as well the features of the activities, are relevant considerations when determining a suitable height.

For example, if the intended use of a room is a gymnasium, then gymnastic activities are likely to be undertaken in the room. These activities often involve jumps and flips which require significant space in order to be undertaken safely.

In terms of the occupants, their features and needs are also relevant when determining a suitable height. For example, occupant features and needs would differ between rooms or spaces intended as a child’s play area, and rooms or spaces intended for adult’s indoor cricket.

The method requires consideration of ‘activity traits’, ‘occupant traits’ and ‘activity support level’. Refer to Schedule 1 for more information on these terms.

When determining the activity support level, the method requires consideration of the relevant dimensions of items likely to be located in the room or space, as well as occupant circulation spaces.

Some of these considerations are—

  • stairs and ramps, since the height of the room of the space will change relative to the occupant during incline and decline; and
  • fixed fittings such as lights that may protrude from the ceiling and wash-basins; and
  • domestic services such as air-conditioners, heaters, ceiling fans and heated water systems; and
  • fixed equipment such manufacturing or processing equipment, permanent signage or displays and lifts; and
  • moveable equipment such as whitegoods; and
  • fixed furniture such as built-in wardrobes and permanent seating; and
  • moveable furniture such as wardrobes, desks and beds; and
  • occupant circulation spaces so that occupants can move comfortably and safety around the room or space.

For example, the location and dimensions of a wash-basin is a relevant consideration in determining the activity support level of a bathroom. This is because an occupant will typically need to access the wash-basin whilst standing, which will influence the necessary height of the space.

Another example is the consideration of moveable equipment such as a refrigerator in a kitchen. If the intended use of a space is a kitchen, then it would be unrealistic to determine a sufficient height for the room without considering the height of a typical refrigerator that would be located in the room.

Compliance with H4P4(1) is verified for the provision of natural light in all habitable rooms when the average daylight factor for each window is determined in accordance with the following formula:

Average Daylight Factor=WATθ(1−R2)MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeyqaiaabA hacaqGLbGaaeOCaiaabggacaqGNbGaaeyzaiaabccacaqGebGaaeyy aiaabMhacaqGSbGaaeyAaiaabEgacaqGObGaaeiDaiaabccacaqGgb GaaeyyaiaabogacaqG0bGaae4BaiaabkhacqGH9aqpdaWcaaqaaiaa dEfaaeaacaWGbbaaamaalaaabaGaamivaiabeI7aXbqaaiaacIcaca aIXaGaeyOeI0IaamOuamaaCaaaleqabaGaaGOmaaaakiaacMcaaaaa aa@546B@  
, where—

  1. WMathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4vaaaa@36D0@
    = the net area of the light transmitting area of the window (m2); and
  2. AMathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyqaaaa@36BA@
    = the total area of the internal wall, floor and ceiling surfaces (m2); and
  3. TMathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamivaaaa@36CD@
    = the diffuse light transmittance of the window; and
  4. θMathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeqiUdehaaa@37AA@
    = visible sky angle in degrees, measured in a plane normal to and from the centre of the window; and
  5. RMathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOuaaaa@36CB@
    = the area-weighted average reflectance of area
    AMathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyqaaaa@36BA@
    .

Explanatory information

H4V2 is equivalent to F6V3 in NCC Volume One. Guidance on the use of F6V3 can be found in the Guide to NCC Volume One, and is applicable to the use of H4V2.

For a Class 1 building, compliance with H4P5(1) and H4P5(2)(a) is verified when it is determined that the building under typical conditions in use is provided with sufficient ventilation with outdoor air such that contaminant levels do not exceed the limits specified in Table H4V3.

Table H4V3 Maximum contaminant limits for acceptable indoor air quality
Pollutant Averaging Time Maximum Air Quality Value
Carbon dioxide, CO2 8 hours 850 ppm Note 1
Carbon monoxide, CO 15 minutes 90 ppm
Carbon monoxide, CO 30 minutes 50 ppm
Carbon monoxide, CO 1 hour 25 ppm
Carbon monoxide, CO 8 hours 10 ppm
Formaldehyde, CH2O 30 minutes 0.1 mg/m3
Nitrogen dioxide, NO2 1 year 40 μg/m3 (0.0197 ppm) Note 2
Nitrogen dioxide, NO2 1 hour 200 μg/m3 (0.0987 ppm) Note 2
Ozone, O3 8 hour, daily maximum 100 μg/m3 (0.0473 ppm)
Particulate matter, PM2.5 1 year 10 μg/m3
Particulate matter, PM2.5 24 hour (99th percentile) 25 μg/m3
Particulate matter, PM10 1 year 20 μg/m3
Particulate matter, PM10 24 hour (99th percentile) 50 μg/m3
Total volatile organic compounds 1 hour 500 μg/m3
Table Notes
  1. Based on body odour metric (i.e. 450 ppm above ambient CO2 level of 400 ppm and demand control ventilation provisions in AS 1668.2).
  2. Based on pressure of 101.325 kPa and temperature of 25 degrees (i.e. the conversion is mg/m3 = ppm (molecular weight/24.4)).
NCC Title

Sound insulation

NCC State
NT
NCC Variation Type
Deletion
NCC SPTC Current
Sound insulation

Compliance with H4P6(1) and (3) to insulate against transmission of airborne sound through walls separating dwellings is verified when it is measured in-situ that the wall has a weighted standardised level difference with spectrum adaptation term (DnT,w + Ctr) not less than 45 when determined under AS/NZS ISO 717.1.

(1) Compliance with Performance Requirement H4P7 is verified for a roof or external wall assembly when it is determined that a mould index of greater than 3, as defined by Section 6 of AIRAH DA07, does not occur on—

  1. the interior surface of the water control layer; or
  2. the surfaces of building fabric components interior to the water control layer.

(2) The calculation method for (1) must use—

  1. input assumptions in accordance with AIRAH DA07; and
  2. the intermediate method for calculating indoor design humidity in Section 4.3.2 of AIRAH DA07.

Deemed-to-Satisfy Provisions

(1) Where a Deemed-to-Satisfy Solution is proposed, Performance Requirements H4P1 to H4P7 are satisfied by complying with H4D2 to H4D9.

(2) Where a Performance Solution is proposed, the relevant Performance Requirements must be determined in accordance with A2G2(3) and A2G4(3) as applicable.

Compliance with AS 3740 or Part 10.2 of the ABCB Housing Provisions satisfies Performance Requirement H4P1 for wet areas provided the wet areas are protected in accordance with the appropriate requirements of 10.2.1 to 10.2.6 and 10.2.12 of the ABCB Housing Provisions.

Performance RequirementH4P1 is satisfied for materials and the installation of wet area components and systems if—

  1. building elements in wet areas are water resistant or waterproof in accordance with clauses 10.2.1 to 10.2.6 of the ABCB Housing Provisions; and
  2. they comply with either—
    1. AS 3740 and clause 10.2.12 of the ABCB Housing Provisions; or
    2. 10.2.7 to 10.2.32 of the ABCB Housing Provisions.

Notes: Livable housing design

In a Class 1a dwelling, at least one bathroom and at least one toilet must comply with the ABCB Standard for Livable Housing Design, which may override the requirements of H4D3.

Explanatory information

AS 3740 and the ABCB Housing Provisions contain requirements for shower hobs and shower over bath configurations, however these may only be used in a bathroom that is not subject to the ABCB Standard for Livable Housing Design. Generally, the ABCB Standard for Livable Housing Design only applies to one bathroom per dwelling. Therefore, shower hobs and the like may only be used in any additional bathrooms.

Compliance with Part 10.3 of the ABCB Housing Provisions satisfies Performance Requirement H4P2 for room heights.

Compliance with Part 10.4 of the ABCB Housing Provisions satisfies Performance Requirement H4P3 for facilities.

Explanatory information: Additional requirements

Additional requirements relating to facilities for people with a disability in Class 1b and Class 10a buildings are contained in NCC Volume One. These requirements are based on the Disability (Access to Premises – Buildings) Standards (Premises Standards) which are available from the Australian Government Attorney-General’s Department website at www.ag.gov.au.

Explanatory information: Cross-volume considerations

NCC Volume Three contains a number of plumbing and drainage provisions which are relevant to facilities. These include, but may not be limited to, the following:

Compliance with Part 10.5 of the ABCB Housing Provisions satisfies Performance Requirement H4P4 for lighting.

(1) Except for an exhaust fan from a sanitary compartment, laundry, kitchen or bathroom, Performance Requirement H4P5 is satisfied for a mechanical ventilation system if it is installed in accordance with AS 1668.2.

(2) Compliance with Part 10.6 of the ABCB Housing Provisions satisfies Performance Requirement H4P5 for ventilation.

Compliance with Part 10.7 of the ABCB Housing Provisions satisfies Performance Requirement H4P6 for sound insulation.

NCC Blurbs

Compliance with Part 10.8 of the ABCB Housing Provisions satisfies Performance Requirement H4P7 for condensation management.

Notes

  1. Refer to the guidance in the “Condensation in Buildings Tasmanian Designers’ Guide” – current version available at www.cbos.tas.gov.au. This Guide must be read in conjunction with the NCC.
  2. The strategies listed in the Guide exceed the NCC requirements for condensation management, however are strongly recommended to assist in minimising condensation in cool climates like Tasmania.

Explanatory information

The intent of these requirements is to assist in the mitigation of condensation within a building. The implementation of condensation management measures may not prevent condensation from occurring.

NCC Title

Condensation management

NCC State
TAS
NCC Variation Type
Replacement
NCC SPTC Current
Condensation management

Compliance with Part 10.8 of the ABCB Housing Provisions satisfies Performance Requirement H4P7 for condensation management.

Notes

From 1 May 2023 to 30 September 2023 P2.4.7, V2.4.7 and Part 3.8.7 of NCC 2019 Volume Two Amendment 1 may apply instead of H4P7, H4V5 and H4D9 of NCC 2022 Volume Two. From 1 October 2023 H4P7, H4V5 and H4D9 of NCC 2022 Volume Two applies.

Explanatory information

The intent of these requirements is to assist in the mitigation of condensation within a building. The implementation of condensation management measures may not prevent condensation from occurring.