SMARTER soundproofing will be required now that noise control is no longer a subjectively defined 'frill' in the building process, but rather a quantified set of demands laid down by the Building Code of Australia (BCA) 2004, in force from May 2004.
This is the claim of Australia's Pyrotek Soundguard , who advise that the new demands apply not only to all new buildings (including boarding houses, hostels, guest houses, hotels, motels, apartments, flats, aged care buildings, townhouses, terrace and other "attached" houses), but also to new building work in existing buildings and "change of use" of existing buildings.
"The scope of BCA demands has also been extended, now including the level of airborne noise tolerated through separating walls and floors of adjoining dwellings, minimum impact sound insulation and a sound insulation requirement for ducting, water supply and stormwater pipework," says Soundguard's Philip Cadwallen.
"The performance provisions of the new BCA are quite tightly specified and must either by field-tested for compliance or subjected to 'Deemed-to-Satisfy' approaches, which include sighting results of laboratory testing proving that the wall/floor systems used actually do achieve the laid-down performance."
According to Cadwallen, Soundguard routinely provides such results to satisfy this requirement for the three main soundproofing materials - Wavebar, Silentstep and Soundlag 4525C- needed to cover all three of the above-mentioned specified categories of demand.
"Wavebar is so well known in construction and architectural circles that it is widely used as the generic term for flexible barium-loaded acoustic insulation, wherein the barium layer acts as a heavily-damped membrane absorbing more sound energy, particularly at the hard-to-stop lower frequencies.
"As proof of its performance, Wavebar was used as the noise barrier in the cladding of the forced and induction fans of Wallerang, Liddell, Loy Yang and Torrens Island where it cut noise down to 81.5 dBA compared with other measures which couldn't even get near the 85 dBA maximum required. Its use in the Newcastle Entertainment Centre led to the development of Wavebar Quadzero, meeting a demand for a product scoring zero on all four fire retardancy indexes," says Cadwallen.
"Silentstep for floors, on the other hand, uses high quality Airstep rubber underlay combined with a highly flexible loaded vinyl to achieve an Rw of 28 and is effective against both impact and airborne noises. Its use in a Sydney hotel cut the noise in a room alongside where DJs play loud music by up to 85 per cent as determined by an acoustic engineer engaged by hotel management.
"Last of the trio, Soundlag 4525C, was developed by qualified acoustic engineers, working from National Acoustic Laboratories tests, into a system designed to meet Rw45. Our soundproofing development team achieve this by sandwiching 28 mm of convoluted hydrolysis-resistant acoustic foam with a flexible loaded vinyl and a tough protective layer of reinforced foil that has a Four Zero fire rating.
"There are literally hundreds of different materials and systems available in the Soundguard range. But these are the trio destined to play the major role in meeting the new requirements of a tougher BCA, especially when coupled with sound advice from Soundguard direct or, 24/7, via our interactive product auto-selector at www.soundguard.com.au," Cadwallen concludes.
The new BCA provisions have been adopted by all States and Territories except, for the present, Queensland, WA and NT.