Thursday 24 January 2013

What is Sound Insulation Testing?

Sound insulation testing is the assessment of the sound insulation performance of party walls and party floors between different dwellings. Testing is required once the property is nearing final completion and determines if the minimum Building Regulation standard for sound insulation has been met.

Developers are responsible for arranging testing to demonstrate compliance to Building Control that the Approved Doc E sound insulation regulations have been met. The procedure is more commonly referred to as pre-completion testing (PCT) or Approved Document E (ADE) sound testing.

What is Approved Doc E?

Approved Document E – ‘Resistance to the passage of sound’ came into force on July 1st 2003 and provides minimum sound insulation Building Regulation requirement for newly built and converted residential dwellings as well as the Code for Sustainable Homes. Properties include houses, flats, student residences, care homes, hotels and schools.

Approved Document E of the Building Regulations is a government-issued document providing guidance for architects, developers, building control bodies, building services engineers, and others involved in the design and conversion of buildings for residential purpose. The document explains the testing requirement and provides advice and details about building procedures and materials that affect test results


What is the benefit of a Sound Test?

In buildings sound can be defined as 'airborne sound' (i.e. sound generated and transferred directly in the air by talking or home entertainment systems) or 'impact sound' (i.e. sound generated by the impact of an object striking the floor and transmitted through it, such as footfall noise).

The objective of Approved Document E is to raise sound resistance standards for both airborne and impact noise between dwellings to provide reasonable living conditions and improve the standards of acoustic insulation in attached properties

Sound insulation testing may also be required in non-residential buildings such as schools, hospitals and workplaces to ensure that noise sensitive areas such as classrooms, wards and meeting rooms are suitably insulated from noisier areas


Do I need a sound test?

All new and converted dwelling houses and flats for residential purpose require sound testing to Approved Document E standard. This also includes a room or suite of rooms which is not a dwelling house or a flat but which is used by one or more persons to live and sleep. For example, rooms in hostels, hotels, boarding houses, halls of residence, and residential homes.

Detached properties do not require sound testing and new constructions that have been built and appropriately registered with the Robust Details scheme do not need to be sound tested. Historic building conversions may not need to be sound tested but often a ‘test and declare’ certificate for sound insulation performance is requested by the Building Control Officer (BCO).

Is my build ready for a Sound Test?



Sound insulation tests are undertaken when the development is “pre-completed”. This means that the test rooms should be at a stage where just final finishing, such as painting and carpets are required. 

Soundguard Acoustics has provided a site checklist below to assist you with this. By ensuring that you meet the requirements of the checklist then the build can be deemed to be at a stage ready for soundinsulation testing. Where items are not in place this will negatively affect the sound insulation performance of the build.
  

  • Windows should be fully installed, glazed & closable
  • Trickle vents and other ventilation systems should be fitted
  • Internal & external doors must be hung, glazed & closable 
  • All wall, floors & ceiling constructions must be completed
  • Skirting boards should all be fitted & cornice where fitted
  • Electrical sockets, TV Aerial sockets & light switches should be fitted
  • Rooms must be clear of building materials, tools & unfurnished
  • No cosmetic floor coverings should be fitted (i.e. laminate, carpet, vinyl, ceramics)
  • No trades should be working in the dwellings during the tests
  • Access to rooms either side of the separating structure is essential
  • Non-tester access to the rooms is prohibited during testing
  • No noisy operations (drilling, cutting or groundwork) to occur nearby during testing
  • Provision of 240v 50Hz mains power is required within the dwellings

How many sound tests do I need?



One set of sound tests needs to be undertaken for every ten flats or houses, provided the construction system is the same. A set means that the test should include two locations where the party element (wall or floor) is tested.

This is equivalent to two individual sound tests when assessing the performance of a wall (airborne performance only) and four individual tests when assessing a floor (two airborne and two impact tests).  All tests must be undertaken between habitable spaces (e.g. bedrooms, living rooms) and not to or from common spaces such as stairwells and corridors.

Approved Document E 2003 states that a minimum of 10% of all party walls and floors is sound tested for every construction group or sub-group. This means that where variations in the construction may occur then further testing may be required.

  • Houses: a set of tests would usually comprise of two airborne sound insulation tests of a pair of separating walls
  • Flats:a set of tests would usually comprise of two airborne sound insulation tests on separating walls; two airborne sound insulation tests of separating floors and two impact sound transmission tests of separating floors 
  • Rooms for Residential Purposes: (student residences, hotel rooms & care homes) a set of tests would usually comprise of one airborne sound insulation test of a separating wall; one airborne sound insulation test of a separating floor and one impact sound transmission test of a separating floor

Where do I find an approved Sound Tester?



Approved Document E states that the sound insulation testing body should be either a member of the Association of Noise Consultants (ANC) and have joined their PCT registration scheme or be registered testers with the United Kingdom Accreditation Service (UKAS). 

Choosing an accredited company under these schemes gives you the peace of mind that your reports will be accepted by all local authorities, building control and national guarantee companies. 

By using an ANC member registered under the PCT registration scheme, such as Soundguard Acoustics Ltd, then you will receive a full report including instruction for your Building Control Officer for accessing the secure online testing certificates for your build. Soundguard Acoustics will also liaise with and release the report directly to your BCO if required.

For sound testing in the Southwest follow these links: SOUTHWEST | DEVON | SOMERSET



What if I use an unregistered company?

Don’t! The quality and validity of the testing and results may be questionable and may not be accepted by the necessary approval bodies. It is likely that your BCO will ask for further or repeated testing by an accredited test company to validate the results. This will result in delay for your project and further payment to the accredited test company.

How is a build Sound Tested?



Airborne sound insulation test (walls & floors):  A controlled noise is generated by an amplifier and loudspeaker across a broad range of frequencies. The generated noise is very loud and can be in excess of 100dB. Initial measurements are taken using a Sound Level Meter within the ‘source room’ followed by further measurements in the ‘receiver room’ on the other side of the wall or floor under investigation. The source room speaker position is then changed and the measurements repeated either side of the partition under test.

Background noise measurements are made using a sound level meter in the receiving room and are used to apply appropriate corrections for external sound such as traffic noise. Similarly the reverberation time (the time taken for sound to decay by 60dB) is measured within the receiving room using the sound source and a sound level meter to determine the corrections that must be applied to account for the characteristics and absorptiveness of the room. 

The difference in the two airborne noise levels (for walls and floors), corrected for background and reverberation characteristics determines the airborne sound insulation performance of the wall, or floor. A greater airborne noise difference between the source room and the receiver room determines a higher airborne sound insulation performance.

Impact sound transmission test (floors only):  This test is different, a calibrated ‘tapping machine’ which comprises of five 'hammers' driven up and down by a cam and electric motor is used to "tap" the floor surface by applying a known force on the floor structure. The machine is placed in several pre-determined positions. The resulting noise is measured in the dwelling below, using a sound level meter.

Background noise measurements are made using a sound level meter in the receiving room and are used to apply appropriate corrections for external sound such as traffic noise. Similarly the reverberation time (the time taken for sound to decay by 60dB) is measured within the receiving room using the sound source and a sound level meter to determine the corrections that must be applied to account for the characteristics and absorptiveness of the room. 

The measured noise levels in the receiving room (for impact floors tests), corrected for background and reverberation characteristics determines the impact sound insulation performance of the floor. For the impact noise the lower the measured level, the better the performance as less sound is being transmitted into the dwelling below.