Improving Sound Transmission Through Floor Partitions

Improving Sound Transmission Through Floor Partitions

In our experience, refurbishment projects usually achieve 30-35dB for airborne sound and 70dB for Impact Sound, if the existing construction has not been acoustically upgraded. These figures do not meet the required 43dB & 64dB as stipulated in Part E of Building Regulations. As sound double every 10dB this is a massive failure and acoustic improvements must be made. Many existing construction consist of a similar construction as shown in as detail 1 below.

Detail 1: Existing Floor Partitions Rated At Approx. 30dB

Failed_sound_Testing_Due_to_existing_floor_Construction_

 

Improving Existing Floor Partitions

There are many ways to reduce the airborne and impact sound transmission through floor partitions, this usually means adding density and isolation to the floor construction. This can be as simple as adding 100mm acoustic wool between the floor joists, then adding resilient bars to the bottom of the existing joists. To the bottom of the acoustic bars add 2 layers of 12.5mm soundboard. to the top of the joists install 18mm floorboard, then an acoustic resilient mat. Then the add the final floor finish e.g. 22mm engineered wooden floors – as per detail 2 shown below). If the aforementioned system is installed strictly inline with manufacturers details it should satisfy the sound insulation requirements of Building Regulations Part E.

Detail 2: Acoustic Flooring Partition Upgrade

Good Conversion Diagram - 15-01-16

Taking the above into account is it essential that robust acoustic design is addressed  from the start of the refurbishment project to prevent potential delays with the building handover due to potential sound testing failures. We can offer acoustic design advice, site survey visits,  sample sound testing and precompletion sound testing to help you achieve successful sound testing at the first attempt.

If you would like advice on your acoustic design or require sound insulation testing in London, please contact us now on 07775623464 or contact us at info@aptsoundtesting.co.uk.

 

 

 

Designing for Sound Insulation

Designing for Sound Insulation

Many of the dwellings in throughout the UK consist of large houses or office blocks that have been converted into flats. Unfortunately during the design stage of the project designing for sound insulation is not always shown the highest priority, so many converted dwellings fail their precompletion testing.

Acoustic_Design_Service

We have helped many of our clients achieve compliance with Part E, by undertaking some simple steps. We can undertake an initial sample sound test of the existing wall and floor construction to ascertain the existing sound insulation levels. Once we have established the sound levels for the existing construction, we can then look at extent of the acoustic upgrades to attain Part E Compliance. This is much more effective than just forwarding an acoustic design that may be to excessive and expensive, especially if the existing floor and/or wall only needs to improve by a minimal amount such as 1-3dB. By having the existing sound levels of the partitions we can recommend targeted, acoustic upgrades to comply with Building Regulations Part E.

Even though the sound insulation levels required to pass Part E for refurbishment projects are less stringent than new build projects – instead of 45dB for airborne its 43dB (2dB less), and for instead of 62dB for Impact Sound Testing its 64dB on new build (2dB more) it is still essential that the acoustic design is shown the highest priory from the start of the project.

Noise_Problems_Failed_Sound_Testing

In our experience, refurbishment projects usually achieve 30-35dB for airborne sound and 70dB for Impact Sound during the sample sound test – if the existing construction has not been acoustically upgraded. These figures do not meet the required 43dB & 64dB as stipulated in Part E of Building Regulations. As sound double every 10dB this is a massive failure and major acoustic improvements must be made.

On all new or converted developments, is it essential that good acoustic design is addressed right from the start of the refurbishment project, so the building passes the sound testing at the first attempt and prevents delays in handover.

If you would like advice on your acoustic design or require sound testing in London, please contact us now on 07775623464 or contact us at info@aptsoundtesting.co.uk.

Acoustic Design Advice for my Sound Insulation Test

Acoustic Design Advice for my Sound Insulation Test

We at APT Sound Testing pride ourselves on offering a comprehensive acoustic design service to help you development attain compliance with Building Regulations Part E at the first attempt. If you send through the relevant drawings such as sections and floor plans during the design stages of the project, we can check the design is adequate and if there appears to be any junctions or details where ‘noise flanking’ may occur, we can then advise if any changes are required to lower the chance of sound test failures.

Acoustic_Design_Service

There are many factors to consider when considering good acoustic design, and they are usually split up into five key factors. If used together or in various combinations they will improve sound insulation properties over a wide range of frequencies. The main factors are:

  1. Mass
  2. Isolation
  3. Absorption
  4. Resilience
  5. Stiffness

Coupled_wall_construction

Also, noise flanking transmission may in some cases be the dominant pathway between adjoining dwellings, especially in existing buildings where you are planning to convert offices/large houses into flats. Here are just a few of the potential noise flanking areas:

  1. Structural Steels
  2. Windows built very close to Internal partitions
  3. Inner leaf of the external wall
  4. External wall cavities
  5. External façade or outer leaf
  6. Roof structure

APT Sound Testing can advise on all types of acoustic design, whether it’s during the initial design of a new build project and/or undertaking sample sound testing and design during a refurbishment/renovation project. We also undertake UKAS accredited sound insulation testing providing a ‘one stop’ solution for all your acoustic requirements.

If you would like more information on our full range of our acoustic services please contact us now at info@aptsoundtesting.co.uk or call Darren direct on 07775 623464.

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

 

 

 

How are Plots Selected for Sound Testing?

How are plots selected for sound testing?

APT usually specifies the amount of sound insulation tests that are required. Firstly we look through the floor plans to work out a testing schedule taking into account the positioning of habitable rooms, the room and partitions sizes. We always tests through ‘habitable rooms’ partitions i.e. lounges & bedrooms wherever possible – as per the details shown below). We will also try and undertake testing across walls and floors in different areas of the building and through different partition types i.e. if one wall is made of masonry and the other met-sec partitioning.  Once we have specified the sound testing schedule, the client should show building control to seek their approval before the commencement of the sound testing.

Detail A – Sound Testing through Walls

Plan_Sound_Test_Through_Walls

Detail B – Sound Testing through Floors

Plan_Sound_Test_Through_Floor

What are the minimum requirements for separating party walls and floors?

The minimum requirements of ADE can depend on a variety of factors such as if the development is new build or refurbished, whether the development is intended to be a permanent dwelling, or classified as “rooms of residential purposes” (e.g. hotels, student accommodation, etc). A brief summary of the minimum requirements can be found below:

DWELLING HOUSES AND FLATS Airborne standard

DnTw,w+Ctr dB

Impact Standard

L’nT,w dB

 

Purpose built dwellings

Walls at least 45 N/A
Floors and Stairs at least 45 up to 62
 

Dwelling formed by material change of use

Walls at least 43 N/A
Floors and Stairs at least 43 up to 64

 

ROOMS FOR RESIDENTAIL PPOSES Airborne standard

DnTw,w+Ctr dB

Airborne standard

L’nT,w dB

 

Purpose-built rooms

Walls at least 43 N/A
Floors and Stairs at least 45 up to 62
 

Rooms formed by material change of use

Walls at least 43 N/A
Floor and Stairs at least 43 up to 64

If you have a project that requires acoustic design advice or sound insulation testing, then please contact us at: info@aptsoundtesting.co.uk or phone me directly on 07775623464.

Approved Document E: Frequently Asked Questions

Approved Document E: Frequently Asked Questions

Why am I required to undertake sound insulation testing?  

Sound insulation and speech privacy are critical for a variety of reasons. Inadequate sound insulation can be extremely distressing to those affected by it and may lead no major noise disputes and legal actions. For example, in an apartment block, your upstairs neighbour may like playing loud music. However, the downstairs occupant may be working nights and sleeping throughout the day, thus any inadequate sound insulation between these two flats would cause great disturbance and distress to the downstairs occupants.

Noise_Problems_Failed_Sound_Testing

 What is precompletion sound insulation testing?

Precompletion sound testing is a building regulation requirement for all new build and dwellings formed by ‘material change of use”, i.e. conversion projects. It has been a requirement that you undertake sound testing on dwellings since 2003. Sound testing should be undertaken to 10% of properties in each development to ensure that the separating walls & floors between habitable rooms of neighbouring properties meet the minimum requirements as defined by Approved Document E, commonly referred to as Approved Document E; for instance:

  • For a pair of semi-detached Houses – a set of tests would usually comprise two airborne sound insulation tests of a separating wall.
  • For Flats (up to 10 units) – a six pack would normally be required, this comprises of: two airborne wall tests, two airborne floor tests and two impact floor sound tests. The easiest way to work out the number of tests required is to multiply 1 x 6 packs for every 10 flats, i.e. if you have 22 flats you will require 3 x 6 packs which equals 18 sound tests in total.
  • For Rooms for Residential Purposes (up to 10 rooms) (student accommodation, hotel rooms, care homes etc.) – a set of tests would usually comprise: one airborne sound insulation tests of a separating wall; one airborne sound insulation test of a separating floor; one impact sound transmission test of a separating floor.

Sound_Testing_Flats

If you would like more information on our full range of our acoustic services, including sound testing, acoustic design and noise surveys, please contact us now at info@aptsoundtesting.co.uk or call Darren direct on 07775 623464.

Upgrading Floor Partitions to Pass Sound Testing

Upgrading Floor Partitions to Pass Sound Testing

In our experience of undertaking hundreds of sample of sound tests throughout London and the Home Counties, refurbishment projects usually achieve 30-35dB for airborne sound and 70dB for Impact Sound, if the existing construction has not been acoustically upgraded. Unfortunately, the aforementioned figures do not meet the required 43dB & 64dB as stipulated in Part E of Building Regulations. As sound double every 10dB this is a massive failure and acoustic improvements must be made. Many existing construction consist of a similar construction as shown in as detail 1 below.

Detail 1: Existing Floor Partitions Rated at Approx. 30dB

Failed_sound_Testing_Due_to_existing_floor_Construction_

Improving Existing Floor Partitions

To reduce airborne and impact sound transmission this usually means adding density and isolation to the floor construction. This can be as simple as adding a drop ceiling consisting of 125mm timber frame. The top of the frame must be a minimum of 25mm below the existing ceiling finish – such as lathe and plaster. Then, to the inside of the timber frame add 100mm of Acoustic Wool and two layers of sound-board tacked to the bottom of the timber frame – all boards to be lapped. This should improve your sound test results by approx. 10-15dB depending on the existing site conditions and quality of the installation – as per Detail 2 below:

Detail 2: Acoustic Flooring Partition Upgrade

ceiling_upgrade_to_pass_sound_test

Taking the above into account is it essential that good acoustic design is addressed right from the start of the refurbishment project, so it prevents delays in handover, i.e. to prevent the dwelling failing the sound testing at building control signoff stage.– a common problem.

If you would like advice on your acoustic design or require sound insulation testing in London, please contact us now on 07775623464 or contact us at info@aptsoundtesting.co.uk.

 

Improving Sound Insulation on Conversion Projects

Improving Sound Insulation on Conversion Projects

In cities throughout the UK there are a huge amount of conversion projects where large Victorian or Georgian houses – or more recently office blocks) have been converted into flats or rooms for residential purposes. Unfortunately designing for sound insulation is not always shown the highest priority on these types of projects, so many converted dwellings suffer from adverse noise transference between the floor and wall partitions. This can be extremely stressful to the occupant’s well-being is a major cause for concern.

architect drafting a house blueprint

architect drafting a house blueprint

We have helped many of our clients achieve compliance with Part E, by undertaking some simple steps. We can undertake an initial sample sound test of the existing wall and floor construction to ascertain the existing sound insulation levels. Once we have established the sound levels for the existing construction, we can then look at extent of the acoustic upgrades to attain Part E Compliance. This is much more effective than just forwarding an acoustic design that may be to excessive and expensive, especially if the existing floor and/or wall only needs to improve by a minimal amount such as 1-3dB. By having the existing sound levels of the partitions we can recommend targeted, acoustic upgrades to comply with Building Regulations Part E.

Sound_Insulation_Testing_Equipment

=The sound insulation levels required to pass Part E for refurbishment projects are less stringent than new build projects. Instead of 45dB for airborne its 43dB (2 dB less), and for instead of 62dB for Impact Sound Testing its 64dB on new build (2 dB more).

Taking the above into account is it essential that good acoustic design is addressed right from the start of the refurbishment project, so it prevents delays in handover, i.e. to prevent the dwelling failing the sound testing at building control sign off stage.– a common problem.

We have offered design advice on hundreds of conversion projects, so we have the experience to help you comply with Building Regulation Part E and achive a sucsessful sound test. If you would like advice on your acoustic design or require sound insulation testing in London, please contact us now on 07775623464 or contact us at info@aptsoundtesting.co.uk.

 

Noise Flanking Paths

Noise Flanking Paths

To reduce the chance of sound testing failure, it is imperative that flanking transmission is considered at the design stage to reduce potential noise flanking paths. 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.

sound_transmission_through_floors

Flanking sound is defined as sound from a source room that is not transmitted via the separating building element e.g. the wall or floor partition. The sound is transmitted indirectly via paths such as external walls, windows, doors and internal corridors. One of the easiest ways of dealing with sound flanking issues is to use isolation strips around the perimeter of the partitions at the edges of floors and walls, this should be finished with acoustic sealant

One of the main reasons for flanking sound test failures is when the inner leaf of the perimeter wall is built with light weight blocks. This acts like a large snare drum and the sound simple travels straight up the wall from one flat to the flat above and/or below. Even if you have used a acoustically robust wall and/or floor partition the sound insulation testing may still fail. If you have used lightweight blocks in your onsite construction and the building fails the sound test you may need to construction independent internal plasterboard lining throughout the inner perimeter wall, this should isolate the lightweight blocks and ensure the flanking path is minimized.

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.

If you would like more information in regards to sound insulation testing and or acoustic design advice, then please call us now at info@airpressuretesting.net or call me (Darren) direct on 07775623464.

Sound Testing Definitions and Terms (1 of 2)

Sound Testing Definitions and Terms (1 of 2) 

Sound testing is usually undertaken near the end of a project to show that the party wall and floor partitions meet the standards shown in Building Regulations Approved Document E.  The method for 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. Sound tests are broken down into various rating methods. The sound insulation definition and terms are as follows:

What is Sound Insulation?

Sound is transmitted through most walls and floors by setting the entire structure into vibration. The higher the transmission loss of a wall, the better it functions as a barrier to the passage of unwanted noise. There are two types of sound insulation testing in buildings: airborne and impact.

Airborne Sound

This is sound caused by vibrations which transmit through a medium and reach the ear or some other form of detecting device. Sound is measured in loudness (decibels (dB)) and frequency (Hertz (Hz)). Airborne sound (or airborne noise) is sound that is transmitted through the air.

Noise_Problems_Failed_Sound_Testing

Impact sound

This is sound arising from the impact of an object on a building element – wall, floor, or ceiling. Typical sources are footsteps, jumping, and dropped objects. Impact sound transmission occurs because the impact causes both sides of the building element to vibrate, which generates sound waves.

Flanking Noise Transmission

Flanking is the transmission of sound from a source room to a receiving room by paths other than straight through the separating wall and/or floor partition. For example, impact sound may be transmitted from one room to another through a common timber floor. Other common mechanisms for flanking transmission include suspended ceilings, pipework, ducting, etc. Flanking sound is always present, except in the ‘ideal’ acoustics laboratory. In practice the sound insulation is often limited by the flanking transmission.

If you have a project that’s needs acoustic design advice or sound insulation testing, then please contact us at: info@aptsoundtesting.co.uk or phone me (Darren) directly on 07775623464.