In homes and offices, sound insulation against air-borne and impact sound is required and at times necessary to ensure comfort.
The noise in a room or hall may originate in 3 ways:
Air borne from a source within the room, e.g. typing office, weaving sheds, engine rooms.
Air borne from external sources.
By impact blows on the structure.
Noise in rooms can be reduced considerably by lining them with high quality sound absorbent material. Twiga Insul, which combats reverberation most effectively is ideal for the purpose.
Structural cross connections or ties between the two partitions should either be avoided, or the minimum number required should be used to cut mechanical linkage to a minimum.
(I) Partitions
When constructing double partitions using Twiga Insul, care should be taken to isolate the two leaves from each other at the edges by means of absorbing material (say fiber felt). In short, the leaves must be fully "floating".
The following are some of the recommended application methods.
Erect a staggered vertical framework of wooden battens (No cross supports).
Interweave Glasswool bypassing it in front of one batten and behind the next for the length of the partition.
Fix lining board only to the battens faced with insulation. Painting, optional.
Note
If a wooden frame has already been erected with cross battens in both vertical and horizontal positions, then strips of absorbing felt should be applied both horizontally and vertically on the battens before fixing the lining board to break the mechanical linkage.
The perforations in the lining board should preferably be on the side of noise source.
Method of application
(II) Wall
Fix horizontal and/or vertical battens (Aluminium or GI Channels) to the walls at suitable centers.
Friction fill Glass Tissue faced glasswool of specified thickness and density between the grid.
Cover insulation with perforated lining board.
With Air Space
To further increase low frequency sound absorption, use horizontal counter battening to provide an air space behind the insulation.
(III) Ceilings
An arrangement of GI Channels/Aluminium Channel system at suitable centers is used either suspended or fixed directly to the ceiling.
HVAC
A. Duct Acoustic Lining
Insulation material for Duct Acoustic Lining shall be resin bonded Twiga Insul with one side factory laminated either black glass woven cloth or black glass tissue. The Thermal conductivity of Twiga Insul for air-conditioning application shall not exceed 0.034 W/m K at 25° C mean temperature and average Noise Reduction Coefficient (NRC=0.80, frequency range from 100Hz to 8000Hz). The density of Insul shall be either 32 Kg/m3 or 48 kg/m3 and the thickness shall not be less than 25 mm.
The installation guideline for glass wool in Duct Acoustic Lining:
The inside duct surface should be cleaned with suitable solvents and rendered free from all physical and chemical impurities.
Fix 22 gauge G.I. channels & angle frame work 25 mm wide x depth equal to thickness of Insul at 600 mm centre, screwed to the sheet metal by means of brass metal screws.
Cut the panels of Insul & fix in framed work using two coats of cold applied bitumen.
CPRX or any other equivalent approved product.
The innermost surface of Insul shall be covered with factory laminated either black glass woven cloth or black glass tissue.
Finally cover the Insul with 0.5 mm thick perforated aluminium sheet having 20% perforation with joints overlapped and screwed to the frame by means of brass metal screws, to produce an even surface.
B. AHU Room Insulation
Plant rooms and AHU room walls and ceiling shall be provided with acoustic treatment to filter out the noise in such plant rooms and shall be provided with acoustic lining with TWIGA Insul -3000/50 suitably factory laminated with Twiga Black Glass Tissue.
Insulation should conform to non-combustibility or incombustibility (BS 476 part 4, IS 8183), A1 fire rating (EN 13501), with limited/zero spread of flames and fire propagation to meet Class 0/Class 1 ( BS 476 part 6 & 7).
Installation guideline
The surface shall be cleaned and frame work of 22 gauge GI fabricated channels 25 mm x 50 mm screwed back to back at 60 cm centers shall be provided vertically and horizontally so that 60 x 60 cm squares are formed.
The gaps between frames shall be lined with a glass wool acoustic insulation with BGT as specified.
The entire surface shall then be covered with 24 gauge perforated aluminium sheet, 60 cm or 120 cm wide having at least 15 percent perforations, fixed with sheet metal screws.
Over-lapping of sheets shall be covered with aluminium beading. The acoustic lining of walls shall be terminated approximately 15 cm above the finished floor to prevent damage to insulation due to accidental water-logging in plant/AHU rooms.
Multiplex, Theatre, Auditorium, Studio and other Sound Spaces
Twiga Insul is selected by nine out of ten sound spaces for its superior acoustic and thermal insulation properties. Twiga Insul is available in a wide range of densities, thicknesses, lengths, and aesthetics.
Recommended Products –
Insul having density of 16 kg/m3 to 32 kg/m3 rolls / 40 kg/m3 to 64 kg/m3 boards can be used with either black glass tissue, white fiber glass tissue or black glass cloth facings and for ceiling, Insul Boards / Tiles with a density of 100 kg/m3 can be used to improve acoustic apart from being fire safe and easy to install.
Acoustic Enclosures
Twiga Insul is preferred for this application due to its following properties –
Resistance to vibration and jolting.
Non corrosive.
Durable/Long life.
Vermin proof.
Noise in rooms can be reduced considerably by lining them with high quality sound absorbent material. Twiga Insul which combats reverberation most effectively is ideal for the purpose.
Structural cross connections or ties between the two partitions should either be avoided, or the minimum number required should be used in order to cut mechanical linkage to a minimum.
(I) Partitions
When constructing double partitions using Twiga Insul, care should be taken to isolate the two leaves from each other at the edges by means of an absorbing material (say fiber felt). In short, the leaves must be fully “floating”.
The following are some of the recommended application methods.
Erect a staggered vertical framework of wooden battens (no cross supports) Interweave Glass Wool bypassing it in front of one batten and behind the next for the length of the partition.
Fix lining board only to the battens faced with insulation.
Painting, optional.
Note
If a wooden frame has already been erected with cross battens in both vertical and horizontal positions, then strips of absorbing felt should be applied both horizontally and vertically on the battens before fixing the lining board to break the mechanical linkage.
The perforations in the lining board should preferably be on the side of noise source.
Method of application:
(II) Wall
Fix horizontal and/or vertical battens (Aluminium or GI Channels) to the walls at suitable centers.
Friction fill glass Tissue faced Glass Wool of specified thickness and density between the grid.
Cover insulation with perforated lining board.
With Air Space
To further increase low frequency sound absorption use horizontal counter battening to provide an air space behind the insulation.
(III) Ceilings
An arrangement of GI Channels/Aluminium Channel system at suitable centers is used either suspended or fixed directly to the ceiling.
