Acoustics

Last updated on Mon, 11/12/2012 - 16:29

Noise in buildings is considered to be detrimental to health and the quality of life.
Where efforts are made to attenuate the sounds coming from the street, the perception of the sounds emitted within the buildings are worsened. Heat insulation policies aiming at reducing energy consumption will also heighten these perceptions.

When comparing performance of drainage materials, acoustic performance is reckoned to be second only to fire safety.
Cast iron pipe systems have intrinsic acoustic properties. Owing to the development in accessories equipment, they offer outstanding performances.

Pipe systems and equipment noise

Noise emitted by waste water pipe systems is classified under the regulation in the «equipment noises».
Noise originating from pipe systems is due to the sound energy produced by water/air turbulence, but mostly by the mechanical effect of the water-flow on the internal pipe walls.

Acoustic comfort is a differentiation criterion that indicates construction quality. The building project manager and the specifier may define together specific requirements to improve the final construction.

Acoustics and SAINT-GOBAIN PAM cast iron pipe systems

Airborne noise

When a material is dense and thick, the pipe walls prevent air transmission; as is the case with cast iron which offers intrinsic acoustic properties.

Structure-borne noise

When the noise produced in a pipe is not transmitted by the air, the residual noise is transmitted by structural vibrations.
Whilst the mass of the cast iron limits the vibratory level, the junctions and fixing to the building will propagate noise. Objective: Dampen the vibrations at the connections with the solid structure

SAINT-GOBAIN PAM's solutions

Vibrations transmitted to the building structure are dampened by installing “sound absorbers” and by combining:

  • couplings equipped with elastomer sealing gaskets which reduce metal to metal contact and prevent the transmission of vibrations.
  •    if required, rubber lined insulating brackets or acoustic dampeners, and stack supports equipped with elastomer gaskets.

In 2008, SAINT-GOBAIN PAM commissioned a series of comparative tests on airborne and structure-borne noises in installation conditions described by standard EN 14366, at the Fraunhofer Institute for Building Physics in Stuttgart.

As all waste water pipe systems manufacturers apply the standard test protocol, it
allows building project managers to compare their results.

Test results for the PAM pipe systems, in accordance with standard EN 14366. 

  Flow rate l/s Airborne noise Structure borne noise
    2 4 8 2 4 8
SMU Plain steel brackets 47 50 54 26 31 34
Rubber lined brackets 48 51 53 19 24 32
Plain steel brckts + PAM Acoustic 48 50 54 5 11 19
               
ENSIGN Ductile iron brackets 45 48 54 27 32 34
Ductile iron brckts + PAM Acoustic 45 47 54 5 11 19 

Airborne or structure-borne noise: All installations with brackets supplied by SAINT-GOBAIN PAM meet all the common requirements of applicable standards. In the event of special requirements, the PAM Acoustic dampeners used with plain brackets give outstanding results far exceeding usual target performances.

 In addition to the acoustic properties of the pipe systems and their accessories, the results obtained may be affected by a number of factors: nature of the partition walls or slabs sealing. To provide clear guidance, SAINT-GOBAIN PAM has carried out additional tests more in conformity with known sites practices: Open hopper or not, changes in the partitions densities.

 *A complete report is available on request