The issue of noise
The World Health Organisation describes noise pollution as noise is one of the top environmental hazards to both physical and mental health and well-being in the European Region stating that excessive noise can seriously harm human health and interferes with people’s daily activities at school, at work, at home and during leisure time. It can disturb sleep, cause cardiovascular and psychophysiological effects, reduce performance and provoke annoyance responses and changes in social behaviour. The effect of noise is subjective and can vary for different individuals but for some, a persistent drip of a tap, for example, can have a greater impact than very loud music. Noisy pipework can be irritating for occupants of building especially as it can occur at any time of day or night. Part E of the Building Regulations (2010) aims to minimise this by stating that sanitary noise in new and refurbished residential properties should not exceed 45 dB as a daytime average.
What causes noisy pipework?
Noise in pipe work is created by water and air passing each other, waste water changing direction at branch pipes and in bends, or passing a reduction, water falling through a vertical soil and waste pipe and hitting a solid surface such as the bend at the bottom. It can then travel through water and pipe walls or radiate from soil and waste pipes. It can also travel via pipe support to building constructions.
Example of noise radiation from flanking building constructions
Examples of where noise can occur
Fraunhofer IBP reports
Most soil and waste pipes will have been tested to provide noise data in impartial test laboratories and in many cases, this will be the Fraunhofer IBP Institute in Germany.
A Fraunhofer IBP report will provide noise test results for both structure-borne and airborne sounds and will also test different flow rates in the pipes. The figures normally used are for a noise measurement taken at a flow rate of two litres, which is the amount of water passing through the pipe from a standard toilet flush. A Fraunhofer IBP report also shows the test construction in detail. For instance, it states which pipe supports and wall thicknesses are used, and describes the standards the test conforms to. Soil and waste pipes are installed in the Fraunhofer IBP test environment on a 115mm plastered concrete wall with a density of 220kg/m2, and a floor or reinforced concrete with a density of 440kg/m2. The rooms are empty and closed.
When choosing low noise and soil and waste pipes, it is important to ensure the correct data is being used. Whilst many will just use the lowest value which will be for the structure-borne result, this doesn’t represent the structure-borne sound in any building and may differ depending on the choice of materials. In particular, the following will influence how much noise from the pipe is reduced:
Airborne is a much more reliable figure and so can be used on the installation site. The noise that the pipe emits itself will be the same, regardless of how it is installed. But you can only use airborne sound on the installation site if the pipe runs in a shaft, or is enclosed in some other way. However, if it is not, you can calculate how and with what you can encapsulate it to meet the building rule requirements.
The risk of simply accepting test results is that a test performed at an inspection may result in you being required to replace the pipes or provide additional noise insulation around them – which takes time and money. Using airborne sound from the pipe as a benchmark means that the reduction value for the building materials is deducted if, for instance, the pipe is installed behind plasterboard, a wall or a ceiling. The result is the level of noise the pipe will emit in a room on the installation site.
Fraunhofer IBP test environment
Fraunhofer IBP test environment
Use the sound check tool
Use our free tool to calculate the noise reduction of Wavin AS+ for your building project. Find the Wavin SoundCheck Tool here.
Reducing noise
Noise reduction can be achieved by careful planning and installation as well as a choice of product.
IMPORTANT! Noise and insulation are a complex affair. If in doubt whether the reduction is sufficient, contact our Technical Support Department for advice. You can also talk to a consulting engineer or acoustics expert.
Shaft insulation
Wavin AS+
No need to worry about adhering to noise regulations with Wavin AS+. Our premium low-noise soil and waste pipe system ticks all the boxes of noise reduction, fire safety and cost-effectiveness. Download the Wavin AS+ BIM package and start designing now!
