Page 125 - GRIHA Manual Volume IV - Introduction to National Rating System
P. 125
116 Griha Manual: Volume 4
The NBC 2005 also lists down the air-borne sound insulation of walls, partitions, and floor
constructions. Some of them are listed below.
Table 2 Sound insulation potential of certain wall or partition and loor constructions
Sound insulation Building component Speciications
dB
26–33 Wall/partition Plywood or wood ibre board 12 mm thick nailed on both sides of 50 mm x 50
mm timber framing members spaced at 400 mm centres.
26–33 Wall/partition Chipboard hollow panels 50 mm thick tongued and grooved edges, hardboard
faced. Joints covered with wood trim.
33–37 Wall/partition Lightweight masonry blockwork. Plaster or dry lining on at least one side.
Overall mass per unit area not less than 50 kg/m .
2
37–43 Wall/partition Lightweight masonry blockwork, plaster or dry lining on at least one side.
Overall mass per unit area not less than 75 kg/m .
2
43–50 Wall/partition Masonry wall, joints well illed. Either plaster or dry lining on both sides. Overall
mass per unit greater than 150 kg/m .
2
Solid Autoclaved Aerated concrete block 215 mm thick plaster or dry lined inish
43–50 Wall/partition on both sides, blockwork joints well illed. Overall mass per unit area should be
greater than 160 kg/m 2
50–54 Wall/partition Either in-situ ore pre-cast concrete wall panel not less than 175 mm thick.
Overall mass per unit should be equal to or more than 415 kg/m
2
2
50–54 Wall/partition Brick wall nominal 230 mm thickness, weight more than 380 kg/m . All joints
should be illed and well inished.
Autoclaved aerated concrete block cavity wall consisting of two leaves, 100 mm
50–54 Wall/partition blocks not less than 75 mm apart. Overall mass per unit area should be more
than 150 kg/m . 2
Cavity lightweight concrete aggregate block (with block of maximum density of
54–60 Wall/partition 1600 kg/m ) with 75 mm cavity and overall mass per unit area greater than 300
3
kg/m . 2
54–60 Wall/partition Solid masonry with an overall mass per unit area of not less than 700 kg/m . 2
49–54 Floor A concrete loor having mass per unit area more than 365 kg/m . 2
49–54 Floor A solid loor consisting of hollow concrete planks; together with a loating loor.
The slab should have a mass per unit area of 300 kg/m or more.
2
Source National Building Code (2005), Part 8, Section 4
Additionally, noise levels at construction sites can be controlled by using proper construction
planning and scheduling techniques. Locating noisy air-compressors and other equipment away
from the site boundary, along with creating temporary barriers to physically block the noise, can
contribute to reducing noise pollution.
The NBC 2005 also lists down the air-borne sound insulation of walls, partitions, and floor
constructions. Some of them are listed below.
Table 2 Sound insulation potential of certain wall or partition and loor constructions
Sound insulation Building component Speciications
dB
26–33 Wall/partition Plywood or wood ibre board 12 mm thick nailed on both sides of 50 mm x 50
mm timber framing members spaced at 400 mm centres.
26–33 Wall/partition Chipboard hollow panels 50 mm thick tongued and grooved edges, hardboard
faced. Joints covered with wood trim.
33–37 Wall/partition Lightweight masonry blockwork. Plaster or dry lining on at least one side.
Overall mass per unit area not less than 50 kg/m .
2
37–43 Wall/partition Lightweight masonry blockwork, plaster or dry lining on at least one side.
Overall mass per unit area not less than 75 kg/m .
2
43–50 Wall/partition Masonry wall, joints well illed. Either plaster or dry lining on both sides. Overall
mass per unit greater than 150 kg/m .
2
Solid Autoclaved Aerated concrete block 215 mm thick plaster or dry lined inish
43–50 Wall/partition on both sides, blockwork joints well illed. Overall mass per unit area should be
greater than 160 kg/m 2
50–54 Wall/partition Either in-situ ore pre-cast concrete wall panel not less than 175 mm thick.
Overall mass per unit should be equal to or more than 415 kg/m
2
2
50–54 Wall/partition Brick wall nominal 230 mm thickness, weight more than 380 kg/m . All joints
should be illed and well inished.
Autoclaved aerated concrete block cavity wall consisting of two leaves, 100 mm
50–54 Wall/partition blocks not less than 75 mm apart. Overall mass per unit area should be more
than 150 kg/m . 2
Cavity lightweight concrete aggregate block (with block of maximum density of
54–60 Wall/partition 1600 kg/m ) with 75 mm cavity and overall mass per unit area greater than 300
3
kg/m . 2
54–60 Wall/partition Solid masonry with an overall mass per unit area of not less than 700 kg/m . 2
49–54 Floor A concrete loor having mass per unit area more than 365 kg/m . 2
49–54 Floor A solid loor consisting of hollow concrete planks; together with a loating loor.
The slab should have a mass per unit area of 300 kg/m or more.
2
Source National Building Code (2005), Part 8, Section 4
Additionally, noise levels at construction sites can be controlled by using proper construction
planning and scheduling techniques. Locating noisy air-compressors and other equipment away
from the site boundary, along with creating temporary barriers to physically block the noise, can
contribute to reducing noise pollution.
