Preparing for Sound Testing
For APT to undertake accurate sound testing we require that certain guidelines are followed, i.e. keeping site noise levels to be kept to a minimum etc. To record accurate test measurements, relatively quiet conditions are required on-site throughout the testing. Any site operatives working in the testing area will have to leave temporarily and any noisy works in the vicinity of the test areas including external site activity such as groundworks, drilling and banging will need to be halted, otherwise, it may result in a sound test failure.  We always provide a full sound testing checklist within our quotation which identifies what actions need to be undertaken prior to the sound insulation test.

The condition the buildings/dwelling is very important, as they can influence the results of the test. The following stages for sound testing will help preparation and also assess the point at which completed buildings can be tested. Generally before the test the parts of the building/rooms either side of the separating wall or separating floor should be complete.

Particular attention should be paid to the following:

1.    All separating floors and walls and all flanking walls and floors should be complete.

2.    All wall and floor junctions should be complete – to include flanking strips etc.

3.    All wall finishes should be complete, this should include skirting’s being in place. This does not include decorative finishes such as paint.

4.    Floors must be bare and no carpets should be laid – where a concrete floor with bonded resilient cover is to be fitted with wood based flooring. In this case, the test sample resilient floor cover should be tested with a wood based floor covering laid over the test sample area.

5.    Windows should be installed with all glass fitted.

6.    Trickle vents should be in place and closed.

7.    All doors should be fully fitted and closed. This includes internal doors and external doors fully fitted with doors seals.

8.    Services should be complete and any voids around ducts finished.

9.    Electrical sockets should be fitted.

10.   A 240V electricity supply should be available to all the test plots.

11.   There should be no noise during the test other than from the testing equipment.

12.   The test plots and adjacent areas within the building should be quiet for the duration of the test.

13.   No work should be carried out or noise made in the building at the time of the test.

14.   Site workers should not enter the building or be in the parts of the building undergoing a test.

After the sound insulation test a report or certificate should be provided in compliance with Building Regulations Part E.

This normally provides the following information:

1.    The company name and/or testers name and address that carried out the test and the accreditation held by the membership organisation.

2.    The client/applicant name.

3.    Site address.

4.    Plots tested

5.    If it was a wall or floor test.

6.    List of equipment used (including details on calibrated equipment) and testing technique.

7.    Confirmation that the test was in accordance with BS EN ISO 140 Part 4 (airborne) and Part 7 (impact).

8.    Measurement procedure.

9.    The results should be calculated in accordance with BS EN ISO 717-1 and 717-2 1997. Detailed test results giving a declaration of a pass or fail.

10.   Date of test. The test results or certificates will be submitted to the verifier during the completion certificate process.

The test duration depends on the amount of tests required on the project. Taking into account standard site conditions a set of tests on houses -two airborne walls will take one to two hours. A six pack of tests on flats, consisting of two airborne walls, two airborne floor and two impact tests will take between two to three hours. Throughout the sound testing we will require full free uninterrupted access to the units/rooms in all test areas.

We offer an acoustic design service to review the construction detailing. We also offer a sample testing service along with site inspections which provides a ‘one stop acoustic solution’. We visit site during the build process to check for any workmanship issues that may cause problems during the final pre-completion sound testing.

If you would like APT Sound Testing to review your site’s acoustic construction, then please speak to us about our acoustic design service. Call us today on 01525 303905 or alternatively visit the APT Sound Testing website for more information.

What Types of Sound Testing are required for Approved Document E?

Sound insulation testing must be carried out on new build and conversion dwellings. The dwellings will either require Airborne and/or impact sound testing depending on the type of dwelling. For houses airborne wall tests are usually required; however, for flats you usually need to carry out airborne wall, airborne floor and impact sound testing.

Here is a brief explanation on the two types of sound insulation tests:

Airborne Sound Tests – Airborne tests are carried out on party walls and floors/ceilings between dwellings. Airborne sound testing measures levels of sound transmitted through the air. We use a Norsonic loudspeaker that produces white noise on one side of the partition, and measure with a decibel meter on the other side how much sound is lost through the partition.

Examples of airborne noise that you usually expect to find in dwellings are people talking, radios and televisions.

Impact Sound Tests – These are only carried out on separating floor/ceiling divides between dwellings – usually on flats. An impact test measures the levels of noise transmitted directly through a separating construction as a result of impact noise, which emulates footfall noise from above. To produce footfall noise we use a tapping machine, which drops metal hammers onto the floor to create impact noise. We then measure the amount of sound that passes through the partition with a decibel meter in the room below the floor partition.

All testing should be carried our between ‘habitable’ rooms. Habitable rooms can be lounges, bedrooms, studies, living rooms and kitchens. Test findings are fed into an Approved Document E complaint report that will be then sent to the client to pass on to the tasked building control body. This sound test report should always be acceptable to Building Control and will help you to get your development signed off.

We provide a turnkey acoustic solution for consultants, project managers and developers from the design stage of developments, right through to the final precompletion testing, ensuring our clients have peace of mind when it comes to the acoustics on their projects.

APT Sound Testing is UKAS accredited to undertake Sound Insulation Testing under ISO/IEC 17025:2017. As a UKAS accredited laboratory we are required to attain the highest standards at all times.

For further information, please see our frequently asked questions section, or to prepare for your sound testing please download our sound test checklist.

For more information please contact us at info@aptsoundtesting.co.uk or call us on 07775623464. Alternately, for more information please visit our website at www.aptsoundtesting.co.uk

Sound Insulation Testing Information for Clients

Sound insulation testing or pre-completion sound testing must be carried out on new build dwellings as well as on converted dwellings. The dwellings will either require an Airborne sound test or an Airborne and Impact sound test. Airborne tests are carried out on separating walls between habitable rooms of dwellings such as houses or flats. Airborne and Impact sound tests are carried out on the separating partition floors between habitable rooms of flats. All sound insulation testing must comply with Approved Document E of Building Regulations.

All of our sound insulation tests are carried out in accordance with ISO 140-4 and ISO 140-7 and we are a UKAS accredited test laboratory, so you can be safe in the knowledge that all our sound testing is carried out to the highest standards in compliance with ISO 17025/2017.

New build properties need to meet the requirements of DnTw+Ctr ≥45dB (more than) and LnTw  ≤62dB (less than).  Conversion properties need to meet the requirements of DnTw+Ctr ≥43dB (more than) and LnTw ≤64dB (less than).

APT Sound Testing test engineers have over 15 years of experience in sound insulation testing throughout London and the South East. We are experts in acoustic consultancy as well as the testing, having completed hundreds of acoustic design projects jobs throughout the UK. We take pride in offering all of our clients a personal and comprehensive acoustic service which is reflected in our positive google reviews and testimonials.  (See our positive customer testimonials here)

We provide a turnkey acoustic solution for consultants, project managers and developers from the design stage of developments, right through to the final precompletion testing, ensuring our clients have peace of mind when it comes to the acoustics on their projects.

What Is Sound Insulation Testing for Approved Document E?

As we have explained, Sound insulation testing must be carried out on new build dwellings as well as on converted dwellings. The dwellings will either require an Airborne sound test or an Impact sound test depending on the dwelling type.

Here is a brief explanation on the two types of sound tests:

Airborne Sound Tests – Airborne tests are carried out on party walls and floors/ceilings between dwellings. Airborne sound testing measures levels of sound transmitted through the air. We use a Norsonic loudspeaker that produces white noise on one side of the partition, and measure with a decibel meter on the other side how much sound is lost through the partition.

Examples of airborne noise that you usually expect to find in dwellings are people talking, radios and televisions.

Impact Sound Tests – These are only carried out on separating floor/ceiling divides between dwellings – usually on flats. An impact test measures the levels of noise transmitted directly through a separating construction as a result of impact noise, which emulates footfall noise from above. To produce footfall noise we use a tapping machine, which drops metal hammers onto the floor to create impact noise. We then measure the amount of sound that passes through the partition with a decibel meter in the room below the floor partition.

All testing should be carried our between ‘habitable’ rooms. Habitable rooms can be lounges, bedrooms, studies, living rooms and kitchens. Test findings are fed into an Approved Document E complaint report that will be then sent to the client to pass on to the tasked building control body. This sound test report should always be acceptable to Building Control and will help you to get your development signed off.

For further information, please see our frequently asked questions section, or to prepare for your sound testing please download our sound test checklist.

APT Sound Testing is UKAS accredited to undertake Sound Insulation Testing under ISO/IEC 17025:2017. As a UKAS accredited laboratory we are required to attain the highest standards at all times.

It is common knowledge that the assessment criteria used by UKAS are internationally recognised as being the best indicators of accurate, impartial and consistent performance. UKAS accreditation demonstrates an organisation’s competence, impartiality and performance capability against internationally recognised standards.

For more information on our Acoustic Design services and Sound Testing services in London, please give me a call direct on 07775 623464  or email us at info@aptsoundtesting.co.uk

Want to Know More About Sound Testing?

Airborne and Impact Sound is transmitted through most walls and floors by setting the entire structure into vibration. This vibration generates new sound waves of reduced intensity on the other side. The passage of sound into one room of a building from a source located in another room or outside the building is termed ”sound transmission”. 

Sound transmission loss or Sound Reduction Index, R dB, is a measure of the effectiveness of a wall, floor, door or other barrier in restricting the passage of sound. The sound transmission loss varies with frequency and the loss is usually greater at higher frequencies. The unit of measure of sound transmission loss is the decibel (dB). The higher the transmission loss of a wall, the better it functions as a barrier to the passage of unwanted noise across the dividing (acoustic) partitions.

Sound Testing Explained

Approved Document E stipulates that there are two types of sound insulation in buildings: airborne and impact. Airborne sound insulation is used when sound produced directly into the air is insulated and it is determined by using the sound reduction index. Impact sound insulation is used for floating floors and it is determined by the sound pressure level in the adjacent room below.

A sound insulation test of a separating partition will be considered as a pass if the airborne sound insulation is equal to or greater than the DnT,w + Ctr value shown for the appropriate dwelling in the table, for airborne testing in new builds properties a figure of 45dB or greater is required and for Impact testing 62dB and below. For conversion properties a figure of 43dB or greater is required and for Impact testing 64dB and below.

What is DnT,w

DnT,w is an in-situ measured performance parameter which demonstrates the level of resistance to sound transmission between two adjacent spaces, such as flats or houses. The measurement will include both direct sound transmission and flanking sound transmission of the construction. Flanking transmission is the effect of sound travelling through the building and may be particularly evident where beams and joists bridge a common partition or along poorly isolated lightweight wall constructions.

The DnT,w of a separating wall or floor will typically be of the order 5 to 7 dB lower than the manufacturers specified Rw (single figure quantity of sound insulation) for the single element, due principally to the contribution from flanking sound transmission around the element when it is built on site – this should always be accounted for in the initial acoustic design.

What is Ctr

Ctr is the spectrum adaption term. It is a correction attributed to the sound insulation quantity to account for urban traffic noise.

What is L’nT,w

L’nT,w is an in-situ measured performance parameter which demonstrates the level of resistance to impact sound transmission between floors. The impact measurement includes both direct sound transmission and flanking sound transmission.

Weighted Sound Reduction Index Rw

When specifying the acoustic performance of an acoustic partition in a more general manner, it can be useful to describe the sound insulation by a single number. The weighted sound reduction index, Rw , is a rating method given in EN ISO 717-1. This standard fits a standard reference curve to the measured sound reduction index curve.

Within the EN ISO 717-1 standard, a rating method is also given where the Rw value is completed by two C-terms which are applied to two models of the noise spectra for various types of noise. These two terms, Rw + C and Rw + Ctr, also include the frequency range 100 – 3150 Hz but can be extended to 50 – 5000 Hz. As industrial and traffic noise often have high sound levels which are also below 100 Hz, it is recommended that the extended frequency area is used.

The summary value, Rw + C, gives the reduction value in dBA for a spectrum with a level which is equally high in all third-octave bands. This can be used for:

•             Highway road traffic travelling at speeds in excess of 80 km/h

•             Factories emitting mainly medium and high frequency noise

•             Living activities (talking, music, radio, TV)

•             Railway traffic at medium and high speed

•             Jet aircraft at a short distance

The summary value Rw + Ctr also gives the reduction value in dBA, spectrum with low-frequency dominance such as:

•             Disco music

•             Urban road traffic

•             Railway traffic at low speeds

•             Factories emitting mainly low and medium frequency noise

Both the impact and airborne insulation performance of floors and walls should be carefully considered from the start of the project to ensure that the minimum performance requirements for new and converted developments are met inline with Approved Document E

If you would like more information in regards to our sound testing and/or noise survey services, please contact us now at info@aptsoundtesting.co.uk.