When your building has noise control requirements, you will need to integrate sound insulation to ensure you stay within the limits for pollution so that employees, visitors, and passers-by are fully protected. To do this, you’ll need to add soundproofing elements that block the transference of unwanted noise, especially through doors and windows.
However, when you’re looking to manage sound levels, it’s vital that you choose elements that will be able to do the job properly. That’s why you should always invest in doors and windows that have undergone acoustic testing to ensure they can reduce noise to a level that’s in line with legal requirements.
In this guide, we’re going to look at what acoustic testing is, why it’s important, and how it works, so that you can make an informed investment in noise control options for your building.
Acoustic testing is a type of product testing that determines how effective building elements are at controlling unwanted noise. Manufacturers can put their products forward for examination to see how much control their doors and windows offer. The result is an acoustic rating that measures the effectiveness of the product, usually presented as a decibel (dB) value representing the level of noise that can be blocked. This rating can help you to calculate which doors are suitable for your needs.
When acoustic testing is undertaken, it must be carried out to meet the requirements of BS EN ISO 10140, the BSI standard that dictates the laboratory measurement of sound insulation in building elements. The most reliable way to do this is to employ a recognised third party to independently certify the acoustic rating of the product, delivering the most reliable and accurate results possible.
Why is acoustic testing important?
Noise pollution is becoming a much bigger problem than ever before: around 75 million residents of European towns and cities are being exposed to levels that exceed those recommended by the World Health Organisation on a regular basis (Sweco). It can have a range of detrimental effects to health, from increasing stress and anxiety levels to causing hearing damage. Therefore, many governments are making noise control a major focus of building regulations in an effort to reduce exposure in the general populace.
Here in the UK, the Building Regulations 2010 Part E dictate the noise control rules and limits that must be followed when carrying out construction work and projects, including the setting of an acceptable noise level in different types of structure. For products making up the envelope of the building or incorporated as part of internal separators, such as windows or doors, it’s important that information on acoustic performance is available so that these regulations can be safely followed. With accurate ratings, it makes it much easier for the appropriate product to be selected.
When acoustic takes place, it must follow the one set out in BS EN ISO 10140 to ensure that the building element is tested fairly and in-line with industry standards. The assessment is made in a purpose-built acoustic suite containing a filler wall that the product is installed within. This wall has a high sound reduction rating, ensuring that noise will only travel through the product being tested. The spaces on either side of the divide are known as the source room and the receiving room.
The process sees pink noise — a type of controlled sound — generated between 90–100 dB in the receiving room of the suite, where a reading of the sound pressure is carried out. A reading is then taken in the receiving room to see how many decibels the level has fallen by. This is repeated in various positions around the suite, with background noise and reverberation intervals monitored and accounted for in the calculation of the acoustic rating.
There are a number of factors that can affect performance during acoustic testing, and they need to be closely checked before commencement to ensure results are accurate. Some of these include:
Correct installation of the building element: It’s important to make sure this the product is installed in the filler wall properly so there are no gaps that could cause noise leakage.
Seal choice and continuity: Before undertaking testing, seals around the product should be checked to see if they’re the right type and there are no breaks. This is because choosing the right type of seal will ensure peak performance, while a gap in the seal will severely reduce the ability for noise control.
Weak corners: The corners of building elements are usually the weakest point and the most likely to compromise acoustic performance. These areas need to be checked for gaps or breaks in the material to ensure accurate testing.
Uneven thresholds: The threshold of the filler wall gap should also be reviewed to make sure it’s fit for purpose with no gaps and a flush fit with the bottom of the door.
Door or window furniture: If the building element being tested is a door or window, any furniture — such as a handle, letterbox, or lock — should be checked to make sure it has been correctly installed without any gaps.
Can acoustic testing be carried out on-site?
In addition to lab-based testing of individual building elements, acoustic testing can also be carried out on-site to gauge the overall sound insulation of a structure. Measurements taken in the field must adhere to BS EN ISO 16283, which ensures all tests are carried out according to regulations.
This type of examination is typically undertaken in new builds or when there has been extensive renovation or conversion work carried out, as it’s stipulated by law in the Building Regulations 2010 Part E. As part of these rules, these projects must demonstrate that they’re able to successfully insulate airborne and impact sound between separating walls and floors.
The Regulations state that this can be done one of two ways: building to Robust Details (a scheme that can be followed during construction that uses design details that have been previously tested) or by carrying out a pre-completion sound test, where an on-site test is carried out by an organisation that is UKAS or ANC registered. This second option is usually favoured, as it allows for greater flexibility and the potential for cheaper or improved sound isolation.
The process of a pre-completion test doesn’t differ that much from the test carried out in a lab: a controlled noise is made on one side of a separating wall or floor and a measurement is taken on the opposing side to see how much insulation is offered. Airborne sound is tested using pink noise, while impact sound is examined using a tapping machine that simulates footsteps. The results are then adjusted to account for reverberation time and background noise. If the structure meets the criteria set out by the Regulations, a passing certificate is awarded.
This guide should have given you a good overview of the acoustic testing process and why it plays a key role in the engineering of quality noise insulation products.
At Bradbury Group, we have extensive knowledge and experience in designing and manufacturing acoustic doors, all of which are independently tested to BS EN ISO 10140 standards by Lorient in their state-of-the-art sound suite. Our M2MAC range of acoustic doorsets comprises of M2M+AC and M2M2AC, available with an ISO 10140 rating from Rw28 to Rw42, depending on specification. These doors are also available with an added CERTIFIRE fire rating or LPCB accredited SR2 security rating. Feel free to get in touch with our team if you would like to find out more.