Ductwork has the side-effect of carrying noise around buildings – from fans or other mechanical systems. Ducts also carry voices from neighbouring rooms. Air-borne noise from inside the ducts emerges into the building through grilles or other system outlets. This distracting ambient noise not only makes it difficult to concentrate, it can also be a health hazard .This type of noise propagation can be effectively treated by lining the inside of the ductwork with a suitable sound-absorbing material.
To protect the inner lining from fibre fallout due to abrasion by high velocity air inside the duct , the insulation should be covered with fibreglass tissue and perforated sheets. These being porous it is impregnable by sound waves and does not affects acoustic property of the system.
Suggested Material for Duct Inner Sound Insulation:
- Fiberglass wool.
- Open Cell Nitrile Rubber Foam