NCC 2022 Volume One - Building Code of Australia Class 2 to 9 buildings
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36
Specification 36 Material properties
Specification 36 Material properties
S36C1
Scope
2019: Spec J1.2: 1
S36C1
Scope
2019: Spec J1.2: 1
This Specification lists the thermal properties of some common construction materials.
2019: Spec J1.2: 1
State variations
S36C1 Scope
To clarify that Specification 36 covers the relevant properties attributed to common construction materials, air films and airspaces, and reflective surfaces.
S36C1 Scope
To clarify that Specification 36 covers the relevant properties attributed to common construction materials, air films and airspaces, and reflective surfaces.
S36C2
Construction Deemed-to-Satisfy
2019: Spec J1.2: 2
S36C2
Construction Deemed-to-Satisfy
2019: Spec J1.2: 2
- For materials which incorporate cores or hollows in regular patterns (such as cored brickwork, hollow blockwork and cored floor or wall panels), the tabulated material densities and thermal conductivities are based on the gross density (mass divided by external dimensions).
- The R-Value of a material is determined by dividing the thickness of the material in metres by the thermal conductivity in Wm-1K-1.
| Description | Density (kg/m3) | Thermal conductivity (Wm-1K-1) |
|---|---|---|
| Steel | 7850 | 47.5 |
| Timber – kiln dried hardwood (across the grain) | 677 | 0.16 |
| Timber – Radiata pine (across the grain) | 506 | 0.12 |
| Description | Density (kg/m3) | Thermal conductivity (Wm-1K-1) |
|---|---|---|
| Aluminium sheeting | 2680 | 210 |
| Concrete or terra cotta tiles | 1922 | 0.81 |
| Steel sheeting | 7850 | 47.5 |
| Description | Density (kg/m3) | Thermal conductivity (Wm-1K-1) |
|---|---|---|
| Aluminium sheeting | 2680 | 210 |
| Autoclaved aerated concrete | 350 | 0.10 |
| 510 | 0.15 | |
| 900 | 0.27 | |
| Cement render (1 part cement to 4 parts sand) | 1570 | 0.53 |
| Clay brick: 2.75 kg | 1430 | 0.55 |
| Clay brick: 3.25 kg | 1690 | 0.65 |
| Clay brick: 3.75 kg | 1950 | 0.78 |
| Concrete block: 190 mm dense or 90 mm dense solid | 1100/2200 | 1.1 |
| Concrete block: 140 mm dense or 190 mm lightweight | 1250/910 | 0.85 |
| Concrete block: 90 mm dense hollow or 90 mm lightweight solid | 1650 / 1800 | 0.75 |
| Concrete block: 140 mm lightweight | 1050 | 0.67 |
| Concrete block: 90 mm lightweight | 1360 | 0.55 |
| Fibre-cement | 1360 | 0.25 |
| Gypsum plasterboard | 880 | 0.17 |
| Pine weatherboards | 506 | 0.10 |
| Plywood | 530 | 0.14 |
| Solid concrete | 2400 | 1.44 |
| Steel sheeting | 7850 | 47.5 |
| Prestressed hollow core concrete panel | 1680 | 0.80 |
| Description | Density (kg/m3) | Thermal conductivity (Wm-1K-1) |
|---|---|---|
| Carpet underlay | - | 0.04 |
| Carpet | - | 0.05 |
| Prestressed hollow core concrete planks | 1680 | 0.80 |
| Particleboard | 640 | 0.12 |
| Plywood | 530 | 0.14 |
| Timber – kiln dried hardwood (across the grain) | 677 | 0.16 |
| Timber – Radiata pine (across the grain) | 506 | 0.10 |
| Solid concrete | 2400 | 1.44 |
| Vinyl floor tiles | 2050 | 0.79 |
| Description | Density (kg/m3) | Thermal conductivity (Wm-1K-1) |
|---|---|---|
| Clay soil (10% moisture content) | 1300 | 0.6 |
| PMMA (polymethylmethacrylate) | 1180 | 1.0 |
| Polycarbonates | 1200 | 0.2 |
| Sand (6% moisture content) | 1800 | 1.64 |
| Soda lime glass | 2500 | 1.0 |
| Position of air film | Direction of heat flow | R-Value |
|---|---|---|
| On a surface with a pitch of not more than 5° | Up | 0.11 |
| Down | 0.16 | |
| On a surface with a pitch of more than 5° but not more than 30° | Up | 0.11 |
| Down | 0.15 | |
| On a surface with a pitch of more than 30° but not more than 45° | Up | 0.11 |
| Down | 0.13 | |
| On a wall | Horizontal | 0.12 |
| Position of air film | Direction of heat flow | R-Value |
|---|---|---|
| Any | Any | 0.03 |
| Position of airspace | Direction of heat flow | R-Value |
|---|---|---|
| In a roof with a pitch not more than 5° or cathedral ceiling with a 20 mm to 50 mm thick roof airspace | Up | 0.15 |
| Down | 0.15 | |
| In a roof with a pitch not more than 5° or cathedral ceiling with a more than 50 mm to 300 mm thick roof airspace | Up | 0.15 |
| Down | 0.17 | |
| In a roof airspace greater than 300 mm thick or with a horizontal ceiling and a roof pitch more than 5° | Up | 0.18 |
| Down | 0.28 | |
| In a wall | Horizontal | 0.16 |
Table Notes
- Linear interpolation may be used to calculate the R-Value of the airspace in a roof with an intermediate pitch.
- A non-ventilated airspace in a roof is one with continuous cover, such as metal or sarked tiles, and no specific provision for ventilation.
-
R-Values are calculated using AS/NZS 4859.2 based on the following:
- summer temperatures of 24°C internally and 36°C externally for heat transfer down; and
- winter temperatures of 18°C internally and 12°C externally for heat transfer up; and
- average of summer and winter results for horizontal heat transfer (e.g. in walls).
- A non-ventilated airspace in a wall is one where there is no express provision for airflow through it and openings to the external environment do not exceed more than 500 mm2 per metre of length in the horizontal direction.
- A non-ventilated airspace in a wall for the purposes of Note (4) includes a wall with drainage openings or weepholes that are open vertical joints in the outer leaf of a cavity masonry wall, which are not regarded as ventilation openings.
| Position of airspace | Direction of heat flow | R-Value |
|---|---|---|
| In a wall with an inner reflective surface of 0.05 emittance and a 20 mm to 100 mm airspace to the wall lining | Horizontal | 0.61 |
| In a wall with a central reflective membrane with an inner surface emittance of 0.05 and a 20 mm to 100 mm airspace from the membrane to the wall lining, and an outer anti-glare emittance of 0.08 and a 20 mm to 100 mm airspace to the wall cladding | Horizontal | 1.1 |
| In a wall with an outer anti-glare reflective surface of 0.08 emittance and a 20 mm to 100 mm airspace to the wall cladding | Horizontal | 0.53 |
Table Notes
- A non-ventilated airspace in a wall is one where there is no express provision for airflow through it and openings to the external environment do not exceed 500 mm2 per metre of length in the horizontal direction.
- A non-ventilated airspace in a wall for the purposes of Note (1) includes a wall with drainage openings or weepholes that are open vertical joints in the outer leaf of a cavity masonry wall, which are not regarded as ventilation openings.
-
R-Values are calculated using AS/NZS 4859.2 based on the following:
- summer temperatures of 24°C internally and 36°C externally for heat transfer down; and
- winter temperatures of 18°C internally and 12°C externally for heat transfer up; and
- average of summer and winter results for horizontal heat transfer (e.g. in walls); and
- emittances are normal emittances of bounding surfaces in accordance with AS 4200.1.
| Position of airspace | Direction of heat flow | R-Value |
|---|---|---|
| In a roof airspace greater than 300 mm thick or with a horizontal ceiling and a pitch more than 5° | Up | Nil |
| Down | 0.46 |
| Direction of heat flow | R-Value of reflective airspace | |
|---|---|---|
| Ventilated roof space | Non-ventilated roof space | |
| Up | 0.34 | 0.56 |
| Down | 1.36 | 1.09 |
Table Notes
- A non-ventilated airspace in a roof is one with continuous cover, such as metal or sarked tiles, and no specific provision for ventilation.
- A reflective surface is a surface with normal emittance of 0.05 or less, in accordance with AS 4200.1.
| Emittance of airspace bounding surfaces | Thickness of roof space | Direction of heat flow | R-Value of reflective airspace |
|---|---|---|---|
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | ≤ 300 mm | Up | 0.43 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 20 mm | Down | 0.60 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 60 mm | Down | 1.16 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 100 mm to ≤ 300 mm | Down | 1.30 |
Table Notes
- A non-ventilated airspace in a roof is one with continuous cover, such as metal, and no specific provision for ventilation.
- Linear interpolation may be used to calculate the R-Value of an airspace of intermediate thickness.
-
R-Values are calculated using AS/NZS 4859.2 based on the following:
- summer temperatures of 24°C internally and 36°C externally for heat transfer down; and
- winter temperatures of 18°C internally and 12°C externally for heat transfer up; and
- emittances are normal emittances of bounding surfaces in accordance with AS 4200.1.
| Emittance of airspace bounding surfaces | Thickness of roof space | Direction of heat flow | R-Value of reflective airspace | ||
|---|---|---|---|---|---|
| 15° to not more than 25° pitch | more than 25° to not more than 35° pitch | more than 35° to not more than 45° pitch | |||
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | ≤ 300 mm | Up | 0.43 | 0.43 | 0.43 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 20 mm | Down | 0.59 | 0.59 | 0.59 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 60 mm | Down | 0.91 | 0.82 | 0.75 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 100 mm to ≤ 300 mm | Down | 0.96 | 0.85 | 0.76 |
Table Notes
- A non-ventilated airspace in a roof is one with continuous cover, such as metal or sarked tiles, and no specific provision for ventilation.
- Linear interpolation may be used to calculate the R-Value of the airspace in a roof with an intermediate pitch.
-
R-Values are calculated using AS/NZS 4859.2 based on the following:
- summer temperatures of 24°C internally and 36°C externally for heat transfer down; and
- winter temperatures of 18°C internally and 12°C externally for heat transfer up; and
- emittances are normal emittances of bounding surfaces in accordance with AS 4200.1.
Explanatory information
Section F of NCC Volume One may require ventilation of roof space in climate zones 6, 7 and 8 to manage risks associated with condensation.
2019: Spec J1.2: 2
State variations
S36C2 Construction Deemed-to-Satisfy
To detail the relevant properties attributed to common construction materials, air films and airspaces, and reflective surfaces.
The values provided in Tables S36C2a to S36C2e are material density values and thermal conductivity (k) values for common construction materials. Tables S36C2f to S36C2m list the R-Values of airspaces and air films, and expected added R-Values provided by a reflective surface. All except the material density can be used in determining the Total R-Value of a roof, wall or floor system.
The term surface density suggests mass per unit volume but in this context is the mass of the full thickness of 1 square metre of wall surface area.
S36C2(4) explains the meaning of a ventilated roof space.
S36C2 Construction Deemed-to-Satisfy
To detail the relevant properties attributed to common construction materials, air films and airspaces, and reflective surfaces.
The values provided in Tables S36C2a to S36C2e are material density values and thermal conductivity (k) values for common construction materials. Tables S36C2f to S36C2m list the R-Values of airspaces and air films, and expected added R-Values provided by a reflective surface. All except the material density can be used in determining the Total R-Value of a roof, wall or floor system.
The term surface density suggests mass per unit volume but in this context is the mass of the full thickness of 1 square metre of wall surface area.
S36C2(4) explains the meaning of a ventilated roof space.
| Description | Density (kg/m3) | Thermal conductivity (Wm-1K-1) |
|---|---|---|
| Steel | 7850 | 47.5 |
| Timber – kiln dried hardwood (across the grain) | 677 | 0.16 |
| Timber – Radiata pine (across the grain) | 506 | 0.12 |
| Description | Density (kg/m3) | Thermal conductivity (Wm-1K-1) |
|---|---|---|
| Aluminium sheeting | 2680 | 210 |
| Concrete or terra cotta tiles | 1922 | 0.81 |
| Steel sheeting | 7850 | 47.5 |
| Description | Density (kg/m3) | Thermal conductivity (Wm-1K-1) |
|---|---|---|
| Aluminium sheeting | 2680 | 210 |
| Autoclaved aerated concrete | 350 | 0.10 |
| 510 | 0.15 | |
| 900 | 0.27 | |
| Cement render (1 part cement to 4 parts sand) | 1570 | 0.53 |
| Clay brick: 2.75 kg | 1430 | 0.55 |
| Clay brick: 3.25 kg | 1690 | 0.65 |
| Clay brick: 3.75 kg | 1950 | 0.78 |
| Concrete block: 190 mm dense or 90 mm dense solid | 1100/2200 | 1.1 |
| Concrete block: 140 mm dense or 190 mm lightweight | 1250/910 | 0.85 |
| Concrete block: 90 mm dense hollow or 90 mm lightweight solid | 1650 / 1800 | 0.75 |
| Concrete block: 140 mm lightweight | 1050 | 0.67 |
| Concrete block: 90 mm lightweight | 1360 | 0.55 |
| Fibre-cement | 1360 | 0.25 |
| Gypsum plasterboard | 880 | 0.17 |
| Pine weatherboards | 506 | 0.10 |
| Plywood | 530 | 0.14 |
| Solid concrete | 2400 | 1.44 |
| Steel sheeting | 7850 | 47.5 |
| Prestressed hollow core concrete panel | 1680 | 0.80 |
| Description | Density (kg/m3) | Thermal conductivity (Wm-1K-1) |
|---|---|---|
| Carpet underlay | - | 0.04 |
| Carpet | - | 0.05 |
| Prestressed hollow core concrete planks | 1680 | 0.80 |
| Particleboard | 640 | 0.12 |
| Plywood | 530 | 0.14 |
| Timber – kiln dried hardwood (across the grain) | 677 | 0.16 |
| Timber – Radiata pine (across the grain) | 506 | 0.10 |
| Solid concrete | 2400 | 1.44 |
| Vinyl floor tiles | 2050 | 0.79 |
| Description | Density (kg/m3) | Thermal conductivity (Wm-1K-1) |
|---|---|---|
| Clay soil (10% moisture content) | 1300 | 0.6 |
| PMMA (polymethylmethacrylate) | 1180 | 1.0 |
| Polycarbonates | 1200 | 0.2 |
| Sand (6% moisture content) | 1800 | 1.64 |
| Soda lime glass | 2500 | 1.0 |
| Position of air film | Direction of heat flow | R-Value |
|---|---|---|
| On a surface with a pitch of not more than 5° | Up | 0.11 |
| Down | 0.16 | |
| On a surface with a pitch of more than 5° but not more than 30° | Up | 0.11 |
| Down | 0.15 | |
| On a surface with a pitch of more than 30° but not more than 45° | Up | 0.11 |
| Down | 0.13 | |
| On a wall | Horizontal | 0.12 |
| Position of air film | Direction of heat flow | R-Value |
|---|---|---|
| Any | Any | 0.03 |
| Position of airspace | Direction of heat flow | R-Value |
|---|---|---|
| In a roof with a pitch not more than 5° or cathedral ceiling with a 20 mm to 50 mm thick roof airspace | Up | 0.15 |
| Down | 0.15 | |
| In a roof with a pitch not more than 5° or cathedral ceiling with a more than 50 mm to 300 mm thick roof airspace | Up | 0.15 |
| Down | 0.17 | |
| In a roof airspace greater than 300 mm thick or with a horizontal ceiling and a roof pitch more than 5° | Up | 0.18 |
| Down | 0.28 | |
| In a wall | Horizontal | 0.16 |
Table Notes
- Linear interpolation may be used to calculate the R-Value of the airspace in a roof with an intermediate pitch.
- A non-ventilated airspace in a roof is one with continuous cover, such as metal or sarked tiles, and no specific provision for ventilation.
-
R-Values are calculated using AS/NZS 4859.2 based on the following:
- summer temperatures of 24°C internally and 36°C externally for heat transfer down; and
- winter temperatures of 18°C internally and 12°C externally for heat transfer up; and
- average of summer and winter results for horizontal heat transfer (e.g. in walls).
- A non-ventilated airspace in a wall is one where there is no express provision for airflow through it and openings to the external environment do not exceed more than 500 mm2 per metre of length in the horizontal direction.
- A non-ventilated airspace in a wall for the purposes of Note (4) includes a wall with drainage openings or weepholes that are open vertical joints in the outer leaf of a cavity masonry wall, which are not regarded as ventilation openings.
| Position of airspace | Direction of heat flow | R-Value |
|---|---|---|
| In a wall with an inner reflective surface of 0.05 emittance and a 20 mm to 100 mm airspace to the wall lining | Horizontal | 0.61 |
| In a wall with a central reflective membrane with an inner surface emittance of 0.05 and a 20 mm to 100 mm airspace from the membrane to the wall lining, and an outer anti-glare emittance of 0.08 and a 20 mm to 100 mm airspace to the wall cladding | Horizontal | 1.1 |
| In a wall with an outer anti-glare reflective surface of 0.08 emittance and a 20 mm to 100 mm airspace to the wall cladding | Horizontal | 0.53 |
Table Notes
- A non-ventilated airspace in a wall is one where there is no express provision for airflow through it and openings to the external environment do not exceed 500 mm2 per metre of length in the horizontal direction.
- A non-ventilated airspace in a wall for the purposes of Note (1) includes a wall with drainage openings or weepholes that are open vertical joints in the outer leaf of a cavity masonry wall, which are not regarded as ventilation openings.
-
R-Values are calculated using AS/NZS 4859.2 based on the following:
- summer temperatures of 24°C internally and 36°C externally for heat transfer down; and
- winter temperatures of 18°C internally and 12°C externally for heat transfer up; and
- average of summer and winter results for horizontal heat transfer (e.g. in walls); and
- emittances are normal emittances of bounding surfaces in accordance with AS 4200.1.
| Position of airspace | Direction of heat flow | R-Value |
|---|---|---|
| In a roof airspace greater than 300 mm thick or with a horizontal ceiling and a pitch more than 5° | Up | Nil |
| Down | 0.46 |
| Direction of heat flow | R-Value of reflective airspace | |
|---|---|---|
| Ventilated roof space | Non-ventilated roof space | |
| Up | 0.34 | 0.56 |
| Down | 1.36 | 1.09 |
Table Notes
- A non-ventilated airspace in a roof is one with continuous cover, such as metal or sarked tiles, and no specific provision for ventilation.
- A reflective surface is a surface with normal emittance of 0.05 or less, in accordance with AS 4200.1.
| Emittance of airspace bounding surfaces | Thickness of roof space | Direction of heat flow | R-Value of reflective airspace |
|---|---|---|---|
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | ≤ 300 mm | Up | 0.43 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 20 mm | Down | 0.60 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 60 mm | Down | 1.16 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 100 mm to ≤ 300 mm | Down | 1.30 |
Table Notes
- A non-ventilated airspace in a roof is one with continuous cover, such as metal, and no specific provision for ventilation.
- Linear interpolation may be used to calculate the R-Value of an airspace of intermediate thickness.
-
R-Values are calculated using AS/NZS 4859.2 based on the following:
- summer temperatures of 24°C internally and 36°C externally for heat transfer down; and
- winter temperatures of 18°C internally and 12°C externally for heat transfer up; and
- emittances are normal emittances of bounding surfaces in accordance with AS 4200.1.
| Emittance of airspace bounding surfaces | Thickness of roof space | Direction of heat flow | R-Value of reflective airspace | ||
|---|---|---|---|---|---|
| 15° to not more than 25° pitch | more than 25° to not more than 35° pitch | more than 35° to not more than 45° pitch | |||
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | ≤ 300 mm | Up | 0.43 | 0.43 | 0.43 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 20 mm | Down | 0.59 | 0.59 | 0.59 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 60 mm | Down | 0.91 | 0.82 | 0.75 |
| Surface 1 emittance 0.9, Surface 2 emittance 0.05 | 100 mm to ≤ 300 mm | Down | 0.96 | 0.85 | 0.76 |
Table Notes
- A non-ventilated airspace in a roof is one with continuous cover, such as metal or sarked tiles, and no specific provision for ventilation.
- Linear interpolation may be used to calculate the R-Value of the airspace in a roof with an intermediate pitch.
-
R-Values are calculated using AS/NZS 4859.2 based on the following:
- summer temperatures of 24°C internally and 36°C externally for heat transfer down; and
- winter temperatures of 18°C internally and 12°C externally for heat transfer up; and
- emittances are normal emittances of bounding surfaces in accordance with AS 4200.1.