NCC 2019 Volume One Amendment 1
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Part F5 Sound transmission and insulation
Floors separating—
a sole-occupancy unit from a plant room, lift shaft, stairway, public corridor, public lobby, or the like, or a part of a different classification, must provide insulation against the transmission of airborne and impact generated sound sufficient to prevent illness or loss of amenity to the occupants.
FP5.1 only applies to a Class 2 or 3 building.
The Objective of this Part is to safeguard occupants from illness or loss of amenity as a result of undue sound being transmitted—
between adjoining sole-occupancy units; and
from common spaces to sole-occupancy units; and
from parts of different classifications to sole-occupancy units.
FO5 only applies to a Class 2 or 3 building or a Class 9c building.
Part F5 addresses sound and its impact on health and amenity, but only within a Class 2, Class 3 and Class 9c buildings. Reasons why it does not cover sound emanating from outside the building include:
A part of a building that separates—
sole-occupancy units; or
a sole-occupancy unit from a part of another classification in the building; or
a sole-occupancy unit from a common space,
is to be constructed to prevent undue sound transmission.
FF5.1 only applies to a Class 2 or 3 building or a Class 9c building.
To achieve FO5 in a Class 2, Class 3 and Class 9c buildings, sound transmission must be minimised through a building element that separates:
Because of its emphasis on building elements which separate sole-occupancy units and sole-occupancy units and common spaces and parts of the building with a different classification, FF5.1 does not cover building elements which separate sole-occupancy units from the outside of a building, and therefore does not cover:
FP5.1 applies to Class 2 and 3 buildings and relates to the floor between sole-occupancy units, sole-occupancy units and specified spaces, and sole-occupancy units and parts of a different classification. It covers both airborne and impact generated sound. FP5.1 covers sound transmission through floors from a number of specified spaces. A list is included with the additional words ‘or the like’. An example of a floor separating sole-occupancy units from parts of a different classification, would be a floor separating ground floor shops from an apartment level above.
Walls separating sole-occupancy units or a sole-occupancy unit from a plant room, lift shaft, stairway, public corridor, public lobby, or the like, or parts of a different classification, must provide insulation against the transmission of—
airborne sound; and
impact generated sound, if the wall is separating a bathroom, sanitary compartment, laundry or kitchen in one sole-occupancy unit from a habitable room (other than a kitchen) in an adjoining unit, sufficient to prevent illness or loss of amenity to the occupants.
FP5.2 only applies to a Class 2 or 3 building.
FP5.2 applies to Class 2 and 3 buildings and relates to the walls between sole-occupancy units, sole-occupancy units and specified spaces, and sole-occupancy units and parts of a different classification. It covers both airborne and impact generated sound. FP5.2(b) covers sound transmission through walls from a number of specified spaces. A list is included with the additional words ‘or the like’. An example of a wall separating sole-occupancy units from parts of a different classification, would be a wall in a building between shops and hotel rooms.
Unlike FP5.1, impact generated sound is only a consideration for walls separating a bathroom, kitchen, sanitary compartment or laundry in one sole-occupancy unit from a habitable room (other than a kitchen) in an adjoining unit.
The required sound insulation of a floor or a wall must not be compromised by—
the incorporation or penetration of a pipe or other service element; or
a door assembly.
FP5.3 only applies to a Class 2 or 3 building.
FP5.3 supports the requirements of FP5.1 and FP5.2 in that the performance of building elements in Class 2 and Class 3 buildings are not to be compromised because of services that penetrate the elements.
Sounds prohibited under FP5.3 include those from a service pipe in the form of:
Floors separating sole-occupancy units must provide insulation against the transmission of airborne and impact generated sound sufficient to prevent illness or loss of amenity to the occupants.
FP5.4 only applies to a Class 9c building.
FP5.4 relates to floors between sole-occupancy units in Class 9c buildings. It covers airborne and impact-generated sounds between units located above one another. It does not cover sound transmission through floors from common spaces, such as a common corridor, laundry or entertainment area.
Walls separating sole-occupancy units, or a sole-occupancy unit from a kitchen, bathroom, sanitary compartment (not being an associated ensuite), laundry, plant room or utilities room, must provide insulation against the transmission of—
airborne sound; and
impact generated sound, if the wall separates a sole-occupancy unit from a kitchen or laundry, sufficient to prevent illness or loss of amenity to the occupants.
FP5.5 only applies to a Class 9c building.
FP5.5 only applies to Class 9c buildings.
For airborne sound, FP5.5 relates to the insulation of walls:
For impact generated sound, FP5.5 relates to the insulation of walls between sole-occupancy units and a kitchen or laundry.
The required sound insulation of a floor or a wall must not be compromised by the incorporation or penetration of a pipe or other service element.
FP5.6 only applies to a Class 9c building.
FP5.6 supports the requirements of FP5.4 and FP5.5 in that the performance of building elements in Class 9c buildings are not to be compromised because of services that penetrate the elements
Sounds prohibited under FP5.6 include those from a service pipe in the form of:
Compliance with FP5.1 and FP5.3 to avoid the transmission of airborne and impact generated sound through floors is verified when it is measured in-situ that the separating floor has—
airborne: a weighted standardised level difference with spectrum adaptation term (DnT,w + Ctr) not less than 45 when determined under AS/NZS ISO 717.1; and
impact: a weighted standardised impact sound pressure level (LnT,w) not more than 62 when determined under AS ISO 717.2.
FV5.1 is a means of verifying whether a floor achieves the requirements of FP5.1 and FP5.3 in minimising the transmission of airborne and impact generated sound through the floor. It only applies to Class 2 and 3 buildings.
It is not compulsory for a designer to use FV5.1. The designer has the choice of using:
If FV5.1 is used to verify compliance, when tested on site the floor must have a weighted standardised level difference with spectrum adaptation term (DnT,w + Ctr) not less than 45, and a weighted standardised impact sound pressure level with spectrum adaptation term (LnT,w) not more than 62.
DnT,w is a measure of airborne sound insulation, similar to Rw. Ctr is a spectrum adjustment factor which adjusts for low frequency sound levels. Ctr has been chosen in recognition of the problems caused by the high bass frequency outputs of modern home theatre systems and music reproduction equipment used by occupants of Class 2 and 3 buildings.
The DnT,w and Ctr must be determined in accordance with AS/NZS ISO 717.1. AS/NZS ISO 717.1 outlines how to use test results to determine the DnT,w and Ctr of a building element. The test results must be obtained by testing the floor in accordance with ISO 140-4. ISO 140-4 is the method for testing the airborne sound insulation of building elements in the field.
LnT,w is a measure of impact sound insulation. The lower the LnT,w, the better the floor’s impact sound insulation rating.
The LnT,w must be determined in accordance with AS ISO 717.2. This document outlines how to use test results to determine the LnT,w and CI of a building element. The test results must be obtained by testing of the floor in accordance with ISO 140-7. ISO 140-7 is the method for testing the impact sound insulation of building elements in the field.
Compliance with FP5.2(a) and FP5.3 to avoid the transmission of airborne sound through walls is verified when it is measured in-situ that—
a wall separating sole-occupancy units 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; or
a wall separating a sole-occupancy unit from a plant room, lift shaft, stairway, public corridor, public lobby, or the like, or parts of a different classification, has a weighted standardised level difference (DnT,w) not less than 45 when determined under AS/NZS ISO 717.1; or
any door assembly located in a wall that separates a sole-occupancy unit from a stairway, public corridor, public lobby, or the like, has a weighted standardised level difference (DnT,w) not less than 25 when determined under AS/NZS ISO 717.1.
FV5.2 is a means for verifying if a wall complies with the requirements of FP5.2(a) and FP5.3 in minimising the transmission of airborne sound through the wall. As with FV5.1 it only applies to Class 2 and 3 buildings.
It is not compulsory for a designer to use FV5.2. The designer has the choice of using:
If FV5.2 is used to verify compliance, when tested on site the wall must have a weighted standardised level difference with spectrum adaptation term (DnT,w + Ctr) not less than 45.
DnT,w is a measure of airborne sound insulation, similar to Rw. Ctr is a spectrum adjustment factor which adjusts for low frequency sound levels. Ctr has been chosen in recognition of the problems caused by the high bass frequency outputs of modern home theatre systems and music reproduction equipment used by occupants of Class 2 and 3 buildings.
The DnT,w and Ctr must be determined in accordance with AS/NZS ISO 717.1. AS/NZS ISO 717.1 outlines how to use test results to determine the DnT,w and Ctr of a building element. The test results must be obtained by testing the wall in accordance with ISO 140-4. ISO 140-4 is the method for testing the airborne sound insulation of building elements in the field.
Unlike FV5.1, the requirements differ depending on the location of the wall. Walls separating sole-occupancy units require a DnT,w + Ctr not less than 45. Walls separating sole-occupancy units and areas such as plant rooms, lift shafts, stairways, public corridors, public lobbies or the like, or parts of a different classification, must have a DnT,w not less than 45. Ctr does not apply in these instances, as the walls separate units from areas that are not likely to produce low frequency noise, which Ctr accounts for.
Door assemblies are permitted in walls between sole-occupancy units and public corridors, stairways or the like, providing the door assembly has a DnT,w not less than 25. Door assemblies are also permitted in walls between sole occupancy units, providing the door assembly has the same level of sound insulation as the wall i.e. DnT,w + Ctr not less than 45.
There is no verification method for determining compliance with FP5.2(b). FP5.2(b) outlines the impact generated sound insulation requirements for walls. Therefore, in this instance the options for compliance are:
Compliance with FP5.4 and FP5.6 to avoid the transmission of airborne and impact generated sound through floors is verified when it is measured in-situ that the separating floor has—
airborne: a weighted standardised level difference (DnT,w) not less than 40 when determined under AS/NZS ISO 717.1; and
impact: a weighted standardised impact sound pressure level (LnT,w) not more than 62 when determined under AS ISO 717.2.
FV5.3 is a means of verifying whether a floor achieves the requirements of FP5.4 and FP5.6 in minimising the transmission of airborne and impact generated sound through the floor. It only applies to Class 9c buildings.
It is not compulsory for a designer to use FV5.3. The designer has the choice of using:
If FV5.3 is used to verify compliance, when tested on site the floor must have a weighted standardised level difference (DnT,w) not less than 40, and a weighted standardised impact sound pressure level (LnT,w) not more than 62.
DnT,w is a measure of airborne sound insulation, similar to Rw.
The DnT,w must be determined in accordance with AS/NZS ISO 717.1. AS/NZS ISO 717.1 outlines how to use test results to determine the DnT,w of a building element. The test results must be obtained by testing the floor in accordance with ISO 140-4. ISO140-4 is the method for testing the airborne sound insulation of building elements in the field.
LnT,w is a measure of impact sound insulation. The lower the LnT,w, the better the floor ’s impact sound insulation rating.
The LnT,w must be determined in accordance with AS ISO 717.2. This document outlines how to use test results to determine the LnT,w of a building element. The test results must be obtained by testing of the floor in accordance with ISO 140-7. ISO 140-7 is the method for testing the impact sound insulation of building elements in the field.
Compliance with FP5.5(a) and FP5.6to avoid the transmission of airborne sound through walls is verified when it is measured in-situ that—
a wall separating sole-occupancy units has a weighted standardised level difference (DnT,w) not less than 40 when determined under AS/NZS ISO 717.1; or
a wall separating a sole-occupancy unit from a kitchen, bathroom, sanitary compartment (not being an associated ensuite), laundry, plant room or utilities room has a weighted standardised level difference (DnT,w) not less than 40 when determined under AS/NZS ISO 717.1.
The LnT,w must be determined in accordance with AS ISO 717.2. This document outlines how to use test results to determine the LnT,w of a building element. The test results must be obtained by testing of the floor in accordance with ISO 140-7. ISO 140-7 is the method for testing the impact sound insulation of building elements in the field.
FV5.4 is a means for verifying if a wall complies with the requirements of FP5.5(a) and FP5.6 in minimising the transmission of airborne sound through the wall. It only applies to Class 9c buildings.
It is not compulsory for a designer to use FV5.4. The designer has the choice of using:
If FV5.4 is used to verify compliance, when tested on site the wall must have a weighted standardised level difference with spectrum adaptation term (DnT,w) not less than 40.