Acoustic Terminology F – L

Acoustic Terminology F – L 

Our previous blog explained the C-F of acoustic terminology, this blog further covers F – L.

Following on from our previous blogs which gave a brief description of

Flanking strip or edge strip

This is a resilient strip using foamed polyethylene normally 5 mm thick, which is located at the perimeter of a floor to isolate the floor boards from the walls and skirtings.

Flanking transmission

This is airborne or impact transmission between rooms that is transmitted via flanking elements and/or flanking elements in conjunction with the main separating elements. An example of a flanking element is the inner leaf of an external wall that connects to the separating ‘core’ of a wall or floor.

Flexible closer

This is a flexible cavity stop or cavity barrier which seals the air path in cavities linking adjoining dwellings.

Floating floor treatment (FFT)

This is a timber floating floor system which may use battens, cradles or platform base, all of which use a resilient layer to provide isolation from the base floor and adjacent wall elements.

Gypsum based plasterboard

This is a dry lining board applied to walls, ceilings and within floating floor treatments which has gypsum content. It may also have fibre reinforcement within the board.

Impact sound

This is sound which is propagated from a noise source through a direct

medium. An example of this is footfall on a floor.

Impact sound transmission

This is sound which is spread from an impact noise source in direct contact with a building element.

Isolation

This is a strategy to limit the number and type of rigid connections between elements of construction.

 L’nT,w

This is the weighted standardized impact sound pressure level. A single-number quantity (weighted) to characterise the impact sound insulation of floors, in accordance with BS EN ISO 717-2: 1997.

If you have a project that requires our acoustic design service and/or sound insulation testing please contact us at info@aptsoundtesting.co.uk or youhone Darren Direct on 07775623464. You can also visit our website at: www.aptsoundtesting.co.uk

 

Acoustic Design Service for London Projects

Acoustic Design Service for London Projects

We have a vast amount of experience in dealing with acoustic partitions on large and small scale construction developments. using this experience we offer easy to follow acoustic design reports which helps provide our clients with a helpful easy to follow turnkey solution for their acoustic requirements. We can usually provide considerable cost and efficiency benefits for all our clients’ new build and conversion projects.

architect drafting a house blueprint

architect drafting a house blueprint

In our experience by simply constructing a robust separating wall or floor this may not in itself provide sufficient sound insulation to pass Building Regulations Part E, as the junctions of each separating wall and/or floor with other parts of the building are equally as important and require careful consideration to prevent noise flanking etc.  Flanking noise transmission can occur via construction components such as:

The most common noise flanking pathways are as follows:

  • Dividing Floor Partitions – Through Floor and Floor Joist Space (if insulation has not been installed or direct fixing to joists without a drop ceiling below the partition under test)
  • Dividing Ceiling Partitions – Above and Through the Ceiling Space (where an adequate acoustic break has not been carried on through the ceiling void)
  • Shared Structural Building Components – Floor Boards, Floor Joists, Continuous Drywall Partitions, Continuous Concrete Floors, and Cement Block Walls.
  • Through Structural Steel (structural steel beams are often a major cause of noise transmission as plasterboard is often fixed directly to the steel without sound breaks)
  • Plumbing Chases – Junctures Between the Walls & Floor Slab Above or at the Exterior Wall Juncture (this should be filed with mortar etc. to add mass to this weakened area)
  • Through Windows (if they are no double glazed or have secondary glazing as a minimum)
  • Fixtures & Outlets – Light Switches, Telephone Outlets, and Recessed Lighting Fixtures (if penetrations have been cut back to back with the opposite dwelling under test)
  • Structural Joints – Perimeter Joints at Wall & Floor, Through Wall & Ceiling Junctures (these should be filled with acoustic mastic)
  • Around the End of the Partition Through the Adjacent Wall (acoustic mastic should be used to seal this junction)

The overall acoustic design and construction should therefore be considered from the offset and not just the separating wall or floor partitions.  Flanking sound transmission through lightweight existing inner walls may be the dominant pathway between adjoining dwellings, when converting existing buildings in to residential dwellings such as offices conversions.

We are UKAS accredited to undertake sound insulation testing of which is done ‘in-house’ which allows us to offer a comprehensive, seamless service from initial design development, without using any outside contractors.

If you would like more information in regards to sound testing please follow our blog at: http://soundtestinguk.blogspot.co.uk/, or contact us at: info@aptsoundtesting.co.uk or visit our website at: www.aptsoundtesting.co.uk

Sound Testing for Approved Document E

Sound Testing for Approved Document E

Approved Document E – ‘Resistance to the passage of sound’ became part of the building regulations on July 1st 2003 and provides minimum sound insulation Building Regulation requirement for new build and conversion dwellings. Properties include houses, flats, hotels, student residences, care homes are all now required to be sound tested under approved document E.

Part E Sound Testing

Part-E-Sound-Testing

Approved Document E is a government issued document providing guidance for developers, architects and building control bodies as well as other bodies involved in the design and conversion of buildings for residential purpose. The document explains the testing requirement for each type of project and provides some good advice and details about building procedures and materials that affect test results.

In Part E it defines the two types of sound – ‘airborne sound, which is sound generated and transferred directly in the air by talking or home entertainment systems such as music systems or Televisions) or ‘impact sound, such as sound generated by the impact of an object striking the floor and transmitted through it, such as footfall noise).

Excessive Noise Problems

Excessive-Noise

The objective of Approved Document E is to raise sound resistance standards and reduce excess noise for tenants for both airborne and impact noise, which in turn will to provide reasonable living conditions and improve the well-being of tenants. 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, notably BREEAM projects usually require sound insulation testing. In rare cases the sound testing of external facades may also be  a requirement.

APT Sound Testing are a UKAS and ISO accredited company.

If you would like more information in regards to our sound testing services please contact us at: info@aptsoundtesting.co.uk or visit our website at: www.aptsoundtesting.co.uk

The Different Types of Sound Insulation Testing

The Different Types of Sound Insulation Testing

Sound Testing has been mandatory requirement since July 2003. All new build dwellings and conversions which were built after this date require 10% of each party wall/floor construction type to be tested.

Sound Insulation Tests needs to be carried out between pairs of rooms separated by party walls or floors, i.e. in block of flats you would undertake airborne testing across the walls and floors; and impact tests across the floors.

Sound_Testing_Flats

You usually try to undertake testing between the two main habitable rooms, such as living rooms and bedrooms. The sound test procedure involves setting up a noise source in a room on one side of the party wall or floor and measuring the noise on both sides of the partition with a class 1 analyser.

Airborne Sound Insulation Tests

Airborne sound insulation tests may be required between horizontally and vertically separated pairs of rooms. The sound tests are undertaken by using a sound source, amplifier and loudspeaker to generate a high noise level in one room (the source room). Noise measurements are then taken in both the source and receiver rooms using a prescribed number of source and microphone positions.

Sample_Sound__Testing

The background levels in the receiver room are measured and the reverberation time in the receiver room is also measured. From the results, the airborne sound insulation (DnT,w + Ctr) is calculated and compared to the requirements of Approved Document E.

Impact Sound Insulation Tests

For vertically separated rooms Impact sound Insulation testing may also be required. This sound test is undertaken using a “tapping machine”, (as above) which drops a series of weights onto the floor of the upper room. The noise level in the lower (receiver) room is measured for a prescribed number of source and microphone locations. The background levels in the receiver room are measured and the reverberation time in the receiver room is also measured. From the results, the impact sound insulation (L’nT,w) is calculated and compared to the requirements of Approved Document E.

Impact Sound Testing

We use the latest Norsonic equipment, which is class one rating and UKAS calibrated. We are a UKAS and ISO accredited company, so you can be assured all our testing is carried out to the strictest quality controlled standards.

If you would like more information in regards to sound testing please follow our blog at: http://soundtestinguk.blogspot.co.uk/, or contact me (Darren) on 07775 623464 ot email us at info@aptsoundtesting.co.uk

Excessive Noise Flanking can lead to Sound Test Failure

Excessive Noise Flanking can lead to Sound Test Failure

Noise Flanking is a term used by acoustic engineers to describe where passes sound over the top or under the primary partition separating the two spaces under test. Noise flanking usually appears due to insufficient isolation of materials thus allowing sound to travel through the partition. Unfortunately excessive noise flanking can lead to a sound test failure.

Noise_flanking

One way to reduce the chance of noise flanking transmission is through a careful consideration to the acoustic design from the start of the project.  Unfortunately, by simply specifying high performance wall and floor partitions it is no guarantee to adequate sound isolation and successful sound testing, extra care must be shown to the mass, isolation and absorption values of the acoustic construction.

APT Sound Testing offer both preconstruction and post construction ‘remedial’ design solutions to achieve a successful sound insulation testing in-line with Part E of Building Regulations. We also offer onsite inspection services to ensure that the sound insulation elements are being installed as per manufactures guild-lines.

Acoustic_Design_Service

Also, in our experience it is never safe to assume because the architect has specified high performance walls, windows and floor/ceiling assemblies that the materials and onsite workmanship will result in compliance with the anticipated results. You should usually reduce the acoustic target by at least 4-5dB due to onsite construction. When the construction assembly is tested in the lab, it is also certified and the installation techniques are described in detail and the construction is undertaken within Laboratory conditions, which is a far more controlled and scrutinised environment. Unfortunately, it is not always possible to replicate Laboratory conditions on site due to its more chaotic nature with multiple trades working next to each other. This is the reason why a 5 point difference is allowed between the construction design on paper and the actual on site sound testing performance.

We have undertaken hundreds of acoustic design reviews on all types of projects to help our client achieve compliance with Building regulations Part E, we provide a ‘one stop’ solution for all your acoustic requirements.

If you would like more information in regards to our acoustic design service and/or sound testing service, please follow our blog at: http://soundtestinguk.blogspot.co.uk or contact us at: info@aptsoundtesting.co.uk or call me ‘Darren’ direct on 07775623464.

 

How Is Sound Insulation Testing Carried Out

How Is Sound Insulation Testing Carried Out?

For airborne wall and floor sound tests, two individual speaker positions are used for each source room; with a total of ten individual 1/3 octave band measurements recorded for both the source and receiver rooms. Measurements are then made to monitor the levels in the receiving room of the tested partition in question. This gives a basic level difference between source and receiver rooms.

Sound_Insulation_Testing_Equipment

This basic level difference is then ‘corrected’ to allow for the reverberation time (the time taken, in seconds, for a noise source to decay by 60 dB) and the existing levels of background noise monitored whilst in the receiving room.

All our tests are carried out in full accordance with BS EN ISO 140-1998 parts 4 (airborne sound testing) and 7 (impact sound testing), and the calculation of all single figure results are done so in accordance with BS EN ISO 717:1.

How do I know when my site is ready for Sound testing?

Sound testing is typically conducted when a development nears completion, and once all internal and external doors and windows have been fitted, it is worth noting that no carpets should be installed prior to the sound testing.

To be able to conduct sound insulation testing we a constant supply of 240V power; we cannot use generator power. We also require a quiet site (a noisy site can make conducting the tests extremely difficult), so no drilling, jack hammers etc. should be used whilst the testing is taking place. We also require full access to all rooms to either side of the dividing partition so if it is a requirement to access a neighbour’s property, this must be arranged prior to the test date.

Noise_during_sound_testing

If you require a sound insulation test than contact us know, we will explain what the test entails and send you our informative checklist to help you prepare for the test. It is our mission to ensure our clients pass their testing at the first attempt. We pride ourselves on providing a ‘one stop acoustic solution’ for all your acoustic requirements.

If you would like more information in regards to our acoustic services, including acoustic design reviews, sound testing and noise surveys please contact us at: info@aptsoundtesting.co.uk or call Darren on 07775623464 or visit our website at: www.aptsoundtesting.co.uk

Why have I failed my Precompletion Sound Testing

Why have I failed my Precompletion Sound Testing?

There are many reasons why dwellings fail precompletion sound testing. If the onsite construction has gaps, cracks or holes it will conduct airborne sounds and can significantly reduce the sound insulation of a construction. For optimum sound insulation a construction must be airtight. Most small gaps can be sealed at the finishing stage using Gyproc jointing compounds. Small gaps or air paths around perimeter Gypframe framework can be sealed with sealant. At the base of the partition, gaps will occur which can be filled with acoustic mastic.

Sound_Insulation_Testing_Equipment

The most common noise flanking pathways are as follows:

  1. Ceiling Partitions – Above and Through the Ceiling Space (where an adequate acoustic break has not been integrated within the ceiling void)
  2. Floor Partitions – Through Floor and Floor Joist Space (if insulation has not been installed or direct fixing to joists without a drop ceiling below the partition under test)
  3. Shared Structural Building Components – Floor Boards, Floor Joists, Continuous Drywall Partitions, Continuous Concrete Floors, and Cement Block Walls.
  4. Through Structural Steel (structural steel beams are often a major cause of noise transmission as plasterboard is often fixed directly to the steel without sound breaks)
  5. Plumbing Chases – Junctures Between the Walls & Floor Slab Above or at the Exterior Wall Juncture (this should be filed with mortar etc. to add mass to this weakened area)
  6. Through Windows (if they are no double glazed or have secondary glazing as a minimum)
  7. Fixtures & Outlets – Light Switches, Telephone Outlets, and Recessed Lighting Fixtures (if penetrations have been cut back to back with the opposite dwelling under test)
  8. Structural Joints – Perimeter Joints at Wall & Floor, Through Wall & Ceiling Junctures (these should be filled with acoustic mastic)
  9. Around the End of the Partition Through the Adjacent Wall (acoustic mastic should be used to seal this junction)

In many instances we have found that existing floor structures of a minimum of 200mm concrete usually achieve the airborne standard as stipulated by Building Regulations Part; however, the impact results are usually poor due to inadequate acoustic insolation between the floor constructions. This is because the airborne sound is easily broken down by the mass of the concrete slab, therefore sounds such as speech & TV etc. are minimised. Unfortunately, impact sound results are poor due to the lack of isolation within the slab, therefore the sound travels straight through the slab to the area below.

Sound_Insulation_Test_London

To help reduce potential control noise issues APT Sound Testing can undertake an acoustic design review of the floors after sample sound testing to ensure both the airborne and impact sound tests are allowed for during our acoustic design service.

If you would like more information in regards to sound testing please follow our blog at: http://soundtestinguk.blogspot.co.uk or contact us at: info@aptsoundtesting.co.uk and 07775623464 or visit our website at: www.aptsoundtesting.co.uk

 

Acoustic Design and Sound Testing

Acoustic Design and Sound Testing

We are currently experiencing a large rise in the amount of housing stock that’s requiring sound testing throughout the UK. As commercial buildings such as offices etc. are converted into residential dwellings sound testing then becomes are requirement under Part E of building regulations. We have carried out a large amount of sound testing in office conversions with varying success as office buildings are not usually designed with acoustics in-mind.

Noise_Problems_Failed_Sound_Testing

To reduce the chance of a sound test failure, it is imperative that flanking transmission is considered at the design stage and any construction detailing is specified to minimise any potential of noise flanking which will downgrade the acoustic performance. Good detailing at the design stage will minimise this effect and optimise the overall levels of acoustic privacy achieved. If designing for residential units, design advice on flanking details must be followed to maximise the possibility of achieving the specified acoustic performance. It is imperative that the design advice is followed, otherwise the site sound insulation values may not meet the performance criteria required and subsequent expensive remedial treatment may be required.

When offices are converted into dwellings we often undertake sample sound testing to check the existing sound levels prior to the commencement of works, once we have established the sound test results we can then come up with a more cost effective design to comply with Part E of Building Regulations.

Historically we have found that if the floor structure is a typical 200mm concrete slab the sample airborne results are coming close to the requirements of Part E without any modifications to the existing slab; however, the impact results are poor. This is because the airborne sound is broken down by the mass of the concrete slab, therefore sounds such as speech & TV etc. are minimised. Unfortunately, impact sound results are poor due to the lack of isolation within the slab, therefore the sound travels straight through the slab to the area below. Sound such as people walking can be very loud and unacceptable.

To help reduce potential control noise issues APT Sound Testing can undertake an acoustic  design review of the floors after sample sound testing to ensure both the airborne and impact sound tests pass Part E of Building Regulations. Using our extensive knowledge regarding the way different materials and construction methods can influence the results of sound testing we can offer easy to follow acoustic advice on the most awkward developments.

Acoustic_Design_Service

If you would like more information in regards to sound testing please follow our blog at: http://soundtestinguk.blogspot.co.uk or contact us at: info@aptsoundtesting.co.uk and 07775623464 or visit our website at: www.aptsoundtesting.co.uk

 

Sound Testing on London Developments

Sound Testing on London Developments 

Sound Insulation Testing is undertaken near the end of a project to show that the party wall and floors meet the Building Regulations Part E stipulated. The method for sound testing for airborne and impact sound insulation is in full accordance with the suggested methods presented in BS EN ISO 140-parts 4 & 7: 1998.

Detached houses don’t require sound insulation testing, however if the house has been built on to the end of an existing house and/or terrace it usually requires 2 airborne wall tests, one test on the lower floor which is usually the living room  ad a second test on the 1st floor through the bedroom walls.

sound_transmission_through_floors

Apartment blocks usually require airborne and impact sound insulation tests. Airborne sound testing is normally required between horizontally and vertically separated pairs of rooms i.e. the wall and floor partitions. The sound tests are undertaken by using a sound source, amplifier and loudspeaker to generate a high noise level in one room (the source room). Noise measurements are then taken in both the source and receiver rooms using a prescribed number of source and microphone positions. The background levels in the receiver room are measured and the reverberation time in the receiver room is also measured. From the results, the airborne sound insulation (DnT,w + Ctr) is calculated and compared to the requirements of Approved Document E.

When undertaking sound testing for floors, impact sound testing may also be required for vertically separated dwellings. Impact sound insulation testing is undertaken using a “tapping machine”, which drops a series of weights/small hammers onto the floor of the upper room. The noise level in the lower (receiver) room is measured for a prescribed number of source and microphone locations. The background levels in the receiver room are measured and the reverberation time in the receiver room is also measured. From the results, the impact sound insulation (L’nT,w) is calculated and compared to the requirements of Approved Document E.

Sound_Testing_Flats

If you have a project that requires sound testing in London then contact us now, we can propose a sound testing schedule that should comply with Part E. Please contact us at: info@aptsoundtesting.co.uk or call us at 07775623464

How Is Sound Insulation Testing Carried Out?

How Is Sound Insulation Testing Carried Out?

For airborne wall and floor sound tests, two individual speaker positions are used for each source room; with a total of ten individual 1/3 octave band measurements recorded for both the source and receiver rooms. Measurements are then made to monitor the levels in the receiving room of the tested partition in question. This gives a basic level difference between source and receiver rooms.

Sound_Insulation_Testing_Equipment

This basic level difference is then ‘corrected’ to allow for the reverberation time (the time taken, in seconds, for a noise source to decay by 60 dB) and the existing levels of background noise monitored whilst in the receiving room.

All our tests are carried out in full accordance with BS EN ISO 140-1998 parts 4 (airborne sound testing) and 7 (impact sound testing), and the calculation of all single figure results are done so in accordance with BS EN ISO 717:1.

How do I know when my site is ready for testing?

Sound testing is typically conducted when a development nears completion, and once all internal and external doors and windows have been fitted, it is worth noting that no carpets should be installed prior to the sound testing.

To be able to conduct sound insulation testing we a constant supply of 240V power; we cannot use generator power. We also require a quiet site (a noisy site can make conducting the tests extremely difficult), so no drilling, jack hammers etc. should be used whilst the testing is taking place. We also require full access to all rooms to either side of the dividing partition so if it is a requirement to access a neighbour’s property, this must be arranged prior to the test date.

If you require a sound insulation test than contact us know, we will explain what the test entails and send you our informative checklist to help you prepare for the test. It is our mission to ensure our clients pass their testing at the first attempt. We pride ourselves on providing a ‘one stop acoustic solution’ for all your acoustic requirements.

If you would like more information in regards to our acoustic services, including acoustic design reviews, sound testing and noise surveys please contact us at: info@aptsoundtesting.co.uk or call Darren on 07775623464 or visit our website at: www.aptsoundtesting.co.uk