NCC 2019 Volume One
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Section F Health and amenity
Part F5 Sound transmission and insulation
NT FP5.1 Sound transmission through floors
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.
Application:
Application:
NT FP5.1 only applies to a Class 2 or 3 building or a Class 9c building.
NT FP5.2 Sound transmission through walls
Walls separating—
(a)
(b)
a sole-occupancy unit from a plant room, lift shaft, stairway, public corridor, public lobby or the like,
must provide insulation against the transmission of airborne and impact generated sound sufficient to prevent illness or loss of amenity to the occupants.
Application:
Application:
NT FP5.2 only applies to a Class 2 or 3 building.
NT FP5.3 Sound transmission through floor and wall penetrations
The required sound insulation of floors or walls must not be compromised by the incorporation or penetration of a pipe or other service element.
Application:
Application:
NT FP5.3 only applies to a Class 2 or 3 building or a Class 9c building.
NT FP5.4 Sound transmission through walls in residential care buildings
Walls separating—
(a)
(b)
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 sufficient to prevent illness or loss of amenity to the occupants; and
(c)
a sole-occupancy unit from a kitchen or laundry,
must provide insulation against the transmission of impact generated sound sufficient to prevent illness or loss of amenity to the occupants.
Application:
Application:
NT FP5.4 only applies to a Class 9c building.
Deemed-to-Satisfy Provisions
NT F5.0 Deemed-to-Satisfy Provisions
(a)
Where a Deemed-to-Satisfy Solution is proposed, Performance RequirementsNT FP5.1 to NT FP5.4 are satisfied by complying with NT F5.1 to NT F5.8.
(b)
Where a Performance Solution is proposed, the relevant Performance Requirements must be determined in accordance with A2.2(3) and A2.4(3) as applicable.
NT F5.1 Application of Part
The Deemed-to-Satisfy Provision of this Part apply to Class 2 and 3 buildings and Class 9c aged care buildings.
NT F5.2 Weighted sound reduction index: Interpretation
A form of construction required to have a certain weighted sound reduction index (Rw) must—
(a)
have the required value determined under AS/NZS ISO 717.1; or
(b)
comply with NT Specification F5.2.
NT F5.3 Sound insulation of floors between units
A floor separating sole-occupancy units must have an Rw not less than 45.
NT F5.4 Sound insulation of walls between units
A wall must have an Rw not less than 45 if it separates—
(a)
(b)
a sole-occupancy unit not within a Class 9c building from a plant room, lift shaft, stairway, public corridor, hallway or the like.
(c)
a sole-occupancy unit in a Class 9c building from a kitchen, bathroom, sanitary compartment (not being an associated ensuite), laundry, plant room or utilities room.
NT F5.5 Walls between a bathroom, sanitary compartment, laundry or kitchen and a habitable room in adjoining unit
(a)
Except for a Class 9c building, a wall 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 must—
(i)
have an Rw of not less than 50; and
(ii)
provide a satisfactory level of insulation against impact sound; and
(iii)
not incorporate a duct which reduces the Rw of the wall to less than 50.
(b)
A wall satisfies (a)(i) and (a)(ii) if it is—
(i)
in accordance with NT Table F5.5; or
(ii)
for other than masonry, in 2 or more separate leaves without rigid mechanical connection except at their periphery; or
(iii)
identical with a prototype that is no less resistant to the transmission of impact sound when tested in accordance with NT Specification F5.5 than a wall listed in NT Table F5.5.
NT Table F5.5 Construction of walls to reduce impact sound
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Construction of walls to reduce impact sound |
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Cavity brickwork— Two leaves of 90 mm brick masonry with— (i) all joints filled solid with mortar; and (ii) an air space not less than 40 mm between the leaves; and (iii) the leaves connected only by ties in accordance with AS 3700. |
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Single leaf brickwork— 110 mm thick brick masonry with— (i) each face rendered 13 mm thick; and (ii) 50 mm x 12 mm thick timber battens at not more than 610 mm centres fixed to each face but not recessed into the render; and (iii) one layer of 12 mm thick softboard nailed to the battens; and (iv) 6 mm thick medium density hardboard adhesive-fixed to the softboard. |
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Concrete blockwork— 190 mm thick concrete block masonry with— (i) each face of the blocks fitted with 50 mm x 50 mm timber battens, spaced at not more than 610 mm centres, screw-fixed into resilient plugs with rubber inserts; and (ii) the space between the battens completely filled with mineral or glass wool blanket or batts not less than 50 mm thick; and (iii) the outer face of the battens finished with plasterboard not less than 10 mm thick or other material with a mass per unit area not less than 7.3 kg/m2. |
NT F5.6 Soil and waste pipes to be separated
If a soil or waste pipe, including a pipe that is embedded in or passes through a floor, serves or passes through more than one sole-occupancy unit—
(a)
the pipe must be separated from the rooms of any sole-occupancy unit by construction with an Rw not less than—
(i)
45 if the adjacent room is a habitable room (other than a kitchen); or
(ii)
30 if the adjacent room is a kitchen or any other room; and
(b)
a door or panel providing access to the pipe must not open into any habitable room (other than a kitchen); and
(c)
an access door or panel in any other part must be firmly fixed so as to overlap the frame or rebate of the frame by not less than 10 mm, be fitted with a sealing gasket along all edges and constructed of—
(i)
wood, particleboard or blockboard not less than 38 mm thick; or
(ii)
compressed fibre reinforced cement sheeting not less than 9 mm thick; or
(iii)
other suitable material with a mass per unit area not less than 24.4 kg/m2.
NT F5.7 Isolation of pumps
A flexible coupling must be used at the point of connection between the service pipes in a building and any circulating or other pump.
NT F5.8 Walls between a bedroom and kitchen or laundry in a Class 9c building
In addition to NT F5.4, a wall separating a sole-occupancy unit in a Class 9c building from a kitchen or laundry must—
(a)
for other than masonry, be two or more separate leaves without rigid mechanical connection except at their periphery; or
(b)
be identical with a prototype that is no less resistant to the transmission of impact sound when tested in accordance with NT Specification F5.5 than a wall listed in Table 2 of NT Specification F5.2.
NT Specification F5.2 Sound insulation for building elements
1. Scope
This Specification lists the weighted sound reduction index (Rw) for some common forms of construction.
2. Construction deemed-to-satisfy
The forms of construction listed in Table 2 are considered to have the Rw stated in that Table if installed as follows:
(a)
Masonry—Units must be laid with all joints filled solid, including those between the masonry and any adjoining construction.
(b)
Concrete slabs—Joints between concrete slabs and any adjoining construction must be filled solid.
(c)
Plasterboard—
(i)
if one layer is required under this Specification, it must be screw-fixed to the studs with joints staggered on opposite faces; and
(ii)
(iii)
joints between sheets or between sheets and any adjoining construction must be taped and filled solid; and
(iv)
fire-protective grade plasterboard must be the special grade manufactured for use in fire-resisting construction.
(d)
Steel studs and perimeter members—
(i)
the section of steel must be not less than 0.6 mm thick; and
(ii)
studs must be not less than 63 mm in depth unless another depth is listed in Table 2; and
(iii)
studs must be fixed to steel top and bottom plates of sufficient depth to permit secure fixing of the plasterboard; and
(iv)
all steel members at the perimeter of the wall must be securely fixed to the adjoining structure and bedded in resilient compound or the joints must be caulked so that there are no voids between the steel members and the wall.
Table 2 R
wApplicable to construction
Construction
R w
(not less than)
WALLS
Clay brickwork—
(a) 230 mm thick in one or more leaves and with a mass per unit area of not less than 290 kg/m2
45
(b) 110 mm thick rendered 13 mm thick on both sides with a mass per unit area of the unrendered wall being not less than 190 kg/m2
45
(c) 110 mm thick, of semi-dry-pressed bricks and rendered 13 mm on one side, the mass per unit area of the unrendered wall being not less than 215 kg/m2
45
(d) 110 mm thick, of extruded brick and rendered 13 mm on one side, the mass per unit area of the unrendered wall being not less than 180 kg/m2
45
Concrete brickwork — 110 mm thick with a mass per unit area of not less than 195 kg/m2
45
Concrete blockwork—
(a) 190 mm thick with a mass per unit area of not less than 215 kg/m2
45
(b) (i) 140 mm thick, the wall thickness of the blocks being not less than 44 mm and with—
45
50 mm x 50 mm timber battens spaced at not more than 610 mm centres screw-fixed on one face of the blocks into resilient plugs with rubber inserts between battens and the wall;
(ii) the face of the battens clad with 13 mm thick standard plasterboard; and
(iii) a mass per unit area of the whole system of not less than 220 kg/m2
Concrete—
(a) In-situ concrete — 125 mm thick and with a density of not less than 2200 kg/m3
45
(b) In-situ concrete — 100 mm thick and with a density of not less than 2500 kg/m3
45
(c) Precast concrete — 100 mm thick and without joints
45
Steel stud walling—
(a) with 2 layers of 16 mm thick fire-protective grade plasterboard fixed to each face
45
(b) with—
45
(i) 1 layer of 13 mm thick fire-protective grade plasterboard fixed to one face, and before fixing, 50 mm thick mineral or glass wool blanket or batts stapled to the back of each sheet so that the sheet is completely covered; and
(ii) 2 layers of 13 mm thick fire-protective grade plasterboard fixed to the other face
(c) with—
45
(i) 1 layer of 16 mm fire-protective grade plasterboard fixed to one face; and
(ii) 50 mm thick mineral or glass wool blanket or batts wedged firmly between the studs; and
(iii) 2 layers of fire-protective grade plasterboard fixed to the other face, the inner layer being 16 mm thick and the outer layer being 13 mm
(d) with 2 layers of 13 mm plasterboard on both sides of 75 mm studs
45
FLOORS—
Concrete—
(a) In-situ concrete slab — 125 mm thick and with a density of not less than 2200 kg/m3
45
(b) In-situ concrete slab — 100 mm thick and with a density of not less than 2500 kg/m3
45
(c) Pre-cast concrete slab — 100 mm thick and without joints
45
Timber — comprising—
(a) timber joists not less than 175 mm x 50 mm; and
45
(b) 75 mm thick mineral or glass wool blanket or batts cut to fit tightly between joists and laid on 10 mm thick plasterboard fixed to underside of joists; and
(c) 25 mm thick mineral or glass wool blanket or batts laid over entire floor, including tops of joists before flooring is laid; and
(d) tongued-and-grooved boards not less than 19 mm thick, secured to 75 mm x 50 mm battens; and
(e) the assembled flooring laid over the joists, but not fixed to them, with the battens lying between the joists
DUCTS OR OTHER CONSTRUCTION SEPARATING SOIL AND WASTE PIPES FROM UNITS
Masonry — not less than 90 mm thick
30
Plasterboard — 2 layers of plasterboard—
(a) each 10 mm thick, fixed to timber studs not less than 75 mm x 50 mm and spaced at not more than 400 mm centres.
30
(b) each 13 mm thick, one on each side of steel studs not less than 50 mm deep and spaced at not more than 400 mm centres
30
3. Method
(a)
The wall constructions to be compared must be tested in accordance with AS 1191.
(b)
A horizontal steel platform 510 mm x 460 mm x 10 mm thick must be placed with one long edge in continuous and direct contact with the wall to be tested on the side of the wall on which the impact sound is to be generated.
(c)
A tapping machine complying with ISO 140/6—1998 (E) must be mounted centrally on the steel platform.
(d)
The sound transmission through the wall must be determined in accordance with AS 1191 except that the tapping machine as mounted on the steel platform must be used as the source of sound.
(e)
The impact sound pressure levels measured in the receiving room must be converted into normalised levels using a reference equivalent absorption area of 10 m2.
NT Specification F5.5 Impact sound — Test of equivalence
1. Scope
This Specification describes a method of test to determine the comparative resistance of walls to the transmission of impact sound.
2. Construction to be tested
(a)
The test is conducted on a specimen of prototype wall construction and on a specimen of one or other of the constructions specified in NT Table F5.5.
(b)
The testing of a construction specified in NT Table F5.5 need not be repeated for subsequent comparisons provided complete records of the results, the test equipment and the technique of testing are kept so that identical equipment can be employed and an identical technique can be adopted in the testing of specimens of prototype wall construction.
3. Method
(a)
The wall constructions to be compared must be tested in accordance with AS 1191.
(b)
A horizontal steel platform 510 mm x 460 mm x 10 mm thick must be placed with one long edge in continuous and direct contact with the wall to be tested on the side of the wall on which the impact sound is to be generated.
(c)
A tapping machine complying with ISO 140/6—1998 (E) must be mounted centrally on the steel platform.
(d)
The sound transmission through the wall must be determined in accordance with AS 1191 except that the tapping machine as mounted on the steel platform must be used as the source of sound.
(e)
The impact sound pressure levels measured in the receiving room must be converted into normalised levels using a reference equivalent absorption area of 10 m2.