The Different Types of Sound testing in London

This article explains the different types of Sound testing in London

There are two different types of sound testing you need to pass to comply with Building Regulations Part E. This article offers a brief description of both.

Airborne Sound Testing in London

The airborne performance requirements of Part E stipulate that new build properties ned to achieve 45dB and converted properties 43dB. This applies both to party walls and floors between properties. This level is the difference between the source level and the receiver level during London sound tests.

If the source level in one flat is 110dB and the receiver level in the neighbouring flat is 55dB, the level difference (or sound reduction performance) is 55dB. Thereafter the measurement is corrected for several factors such as background noise, room characteristics and frequency weighting, giving the final sound insulation performance value of the tested partition.

sound testing equipment

In this case the higher the number achieved the better the sound insulation performance, whereas Impact testing is the opposite, i.e. the lower the figure the better performance. The measurement is done by using a Norsonic Class 1 Analyser, Amplifier and Speaker (as shown below)

Impact Sound Testing In London

Impact sound testing only applies to party floors and related to the effectiveness of the floor construction in absorbing shock such as footfall noise. The measurement is done by using a Norsonic tapping machine (as shown below). The machine has 5 weights which tapping in regular succession on the tested floor which emulates footfall noise. The noise levels are taken in the receiving room below, which are then measured and averaged for different tapper positions, which then gives the sound reduction rating of the floor. In this case the lower the figure, the better the performance.

Impact Sound Testing

If you have a project that’s needs acoustic design advice or Sound Testing in London, then please contact us at: info@aptsoundtesting.co.uk or phone us directly on 07775623464.

Good Acoustic Design for Sound Testing In London

Good Acoustic Design to Help Pass your Sound Testing In London 

Careful acoustic design consideration should be used from the offset of the project to ensure your project passes the Sound Testing In London, whether it’s new built or a conversion project to meet the required requirements Building Regulations Part E. Tackling these two aspects involves different construction techniques and careful acoustic design detailing. This is good news for the new residents as it proves adequate levels of soundproofing have been incorporated into the buildings design and construction.

In many cases, sound test failure can also be down to the poor workmanship rather than the acoustic design, that is why we offer a full acoustic package which includes for site survey visits; that way we have the acoustic design and onsite construction covered, reducing the chance of sound test failure.

NoiseFlankingWall

We offer an acoustic design package, which contains the following elements:

  • Site Survey Visits – to let us view the existing site construction. This allows us to check for potential problematic construction such as inclusion of lightweight blocks in the existing construction. It also lets us check that the installation teams are installing the acoustic materials as per manufacturer’s guidelines.
  • Sample Sound Testing – of the existing construction. This offers an accurate overview of the acoustic performance of the existing partitions which enables us to offer a targeted acoustic design using the sound insulation performance of the existing construction.

Acoustic Design Considerations

  • Avoid the use of lightweight blocks in the inner envelope construction as sound will travel both vertically and horizontally from dwelling to dwelling.
  • The use of resilient suspended ceilings will help improve the performance of the floor partition.
  • Ensure all support steels/timbers are carefully boxed out where they travel from flat to flat vertically and horizontally.
  • Use a high quality resilient acoustic membrane on top of the floor to improve the impact performance of a floor.
  • Ensure all penetrations are fully sealed where they terminate through floors and they are adequately boxed with acoustic quilt and two layers of plasterboard.

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

How Many Sound Tests Do I Need On My Project

How Many Sound Tests Do I Need On My Project?

Our clients often ask ‘how many sound tests do I need on my project’. Part E stipulated that 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 tests when assessing the performance of a wall this means 2 airborne wall, 2 airborne floor and 2 impact sound tests as a minimum wherever possible. 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.

Acoustic Design Advice

Approved Document E 2003 also states that a minimum of 10% of all party walls and floors is sound tested for every type of construction or sub-group, this means where there a variations in the construction of the floors and/or walls may occur then further testing may be required. The amount of sound tests required for each type of development is:

Houses:

On houses two airborne sound insulation tests on a pair of separating walls would be required.

Flats:

On flats a 6 Pack would normally be required, this 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:

On student accommodation, 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 on a separating floor and one impact sound transmission test of a separating floor.

If you are unsure of the amount of sound tests required on your development, please contact us now at: info@aptsoundtesting.co.uk or call me direct on 07775623464.

What Types of Sound Testing Do I Need

 

What Types of Sound Testing Do I Need 

Sound Testing needs to be carried out between pairs of rooms separated by party walls or floors. In most cases, the rooms to be sound tested will be the two main habitable rooms – living rooms and bedrooms. All new build dwellings and conversions which were built after this 2004 are required to have 10% of each party wall/floor construction type to be tested.

 

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. The three types of Sound Tests usually required – depending on the project configuration) are:

sound testing equipment 

Airborne Wall Tests

Airborne wall sound tests may be required between separate dwellings where a lounge and/or bedroom are positioned against the dividing wall partition. 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.

 

Airborne Floor Tests

For vertically separated dwellings, airborne floor sound testing may be required, where a lounge and/or bedroom sit’s against the dividing floor partition above and/or below a ‘habitable’ room. 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.

 

Impact Sound Tests

For vertically separated rooms, an Impact sound test 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.

 

Non-Residential Sound Testing

It is worth noting that sound insulation testing may also be required in non-residential buildings such as schools, hospitals, workplaces, whereas built performance needs to be demonstrated to ensure noise sensitive areas (e.g. classrooms, wards, meeting rooms) are suitably insulated from noisier areas or to comply with BB93 & BREEAM requirements.

 

Sample Sound Testing

If you have an existing building that you are about to convert info flats etc. and need to establish the acoustic performance of the existing partitions, we can undertake sample sound testing on walls and floors to check the sound insulation performance. Thereafter we can forward a targeted acoustic design to comply with Part E of Building Regulations, as well as undertaking the final pre-completion sound testing.

 

All APT’s test engineers carry the latest Norsonic equipment, which are class one rating all of our acoustic testing/sound testing is completed to a strict quality controlled standard. We provide full ISO & UKAS complaint sound testing.

If you would like more information in regards to your air and sound testing please contact us now at info@aptsoundtesting.co.uk or call us on 07775623464

 

controlled standard

Our Pathway to Successful Sound Testing

Our Pathway to Successful Sound Testing

Sound Insulation Site Audits

We can undertake acoustic site audits, to let us view the existing site construction. This allows us to check for potential problematic areas such as the inclusion of lightweight blocks within the existing wall construction. It also lets us check that the installation teams are installing the acoustic materials as per manufacturer’s guidelines, thus avoiding crucial onsite mistakes. In our experience a sound test failure is often due to the poor workmanship rather than the actual design. The site survey visits negate the risk of sound test failure.

We can also undertake sample sound insulation testing of the existing construction. This offers an accurate overview of the acoustic performance of the existing partitions, which enables us to offer a targeted acoustic design which takes into account the performance of the existing construction.

 Acoustic Design Advice

Acoustic Defect Diagnosis & Remedial Advice

With many years’ experience in building acoustics, we are able to diagnose the reasons for the sound test failure and recommend a cost-effective solution. Often, the reasons for the partition failure are obvious to the test engineer in which case the advice will be minimal and subsequently the cost for acoustic design advice will be minimal. Sometimes, there are more technical issues which require more detailed diagnosis and invasive investigation, such as large amounts of noise flanking due to serious design faults, e.g. poor material isolation.

Precompletion Sound Testing

To help enforce good acoustic design principles pre-completion sound testing was introduced July 2003, this resulted in all new build properties and conversions which were built after this date are require 10% of each party wall/floor construction type to be tested.

Precompletion Sound Testing is carried out between pairs of rooms separated by party walls or floors. The two ‘habitable’ areas that usually require sound testing are living rooms and bedrooms, although other rooms can be tested if this is not possible, i.e. kitchen to bedroom.

sound testing equipment

If you need sound insulation testing and acoustic design, please don’t hesitate to contact us at info@aptsoundtesting.co.uk  or call me on 07775623464

IMPROVING SOUND INSULATION ON LONDON REFURBISHMENT PROJECTS

IMPROVING SOUND INSULATION ON  LONDON REFURBISHMENT PROJECTS

Many of our new clients ask ‘ how can we improve our sound insulation on our London Refurbishment projects’. One of the main problems is that a large number of the dwellings in London, consist of flats converted from large Victorian houses. Unfortunately at the time of the building conversion, designing for sound insulation was not a high priority and so many of the 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.

There are ways to improve the airborne and impact performance by improving the wall/floor partitions ability to reduce the amount of sound transmission from one side of a construction element to the other. By isolating the different materials may not be enough its own and you may need to improve the mass of the partition as well.

Video Showing Main Noise Transference Points Through Existing Partitions.

Improving Existing Floor Partitions

In our experience of undertaking hundreds of sound insulation tests in London, 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_

Acoustic Improvements to 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. Detail 2 shows this in more detail.

Detail 2: Acoustic Flooring Partition Upgrade

Simple_floor_upgrade_to_Pass_Sound_Testing

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.

Dealing With Noise Flanking Issues

Dealing With Noise Flanking Issues 

One of the easiest ways of dealing with noise flanking issues is to use isolation strips around the perimeter of the partitions at the edges of floors and walls. Acoustic sealant should also be incorporated wherever possible. 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 testing 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.

This video shows noise flanking through a window reveal.

https://www.youtube.com/watch?v=edhLno7LFzY

To reduce the chance of sound insulation test failures, 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.

 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@aptsoundtesting.co.uk or call us on 07775623464.

Sound Insulation & Noise Flanking

Sound Insulation & Noise Flanking

Sound insulation & noise flanking describes the reduction of sound that passes between two spaces separated by a dividing element, such as a wall or floor partition. The sound energy passes through the dividing element (direct transmission) and through the surrounding structure (indirect or flanking transmission). The  noise reduction attributed to the sound insulation is realised via sound insulation testing.

 When the building’s acoustic design is taken into consideration, it is important to consider both methods of transmission. The dividing walls or floors, which flank/abut the dividing element/s, usually constitute the main paths for flanking transmission, but this can also occur at ventilation ducts, doorways, windows etc. If windows are positioned very close to the dividing partition then noise flanking will usually occur around the main building envelope, thus rendering your ‘high spec’ acoustic solution useless.

sound testing equipment

It is extremely unlikely that figures quoted from ‘laboratory sample’ sound test conditions will be achieved on site, as the laboratory installation is described in detail and followed to the letter. However, due to time constraints etc. it is not always possible to replicate the same conditions on a construction site, which is the reason why a 5dB point difference is allowed between the laboratory and construction site sound insulation performance.

Noise Flanking Paths

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.

NoiseFlankingWall

If you would like more information on sound insulation testing and/or acoustic design service, please contact us at info@aptsoundtesting.co.uk or call us on 07775623464

Excess Noise Between Dwellings

The Reasons for Excess Noise Between Dwellings

There are a variety of reasons why sound insulation may need to be improved. Some of the typical reasons given by occupants, property managers and developers are:

  • Poor workmanship at the time of construction has led to poor sound insulation and noise flanking due to bridging the acoustic elements via incorrect fixings etc. and its damaged the original components.
  • A change in material of wall or floor finishes (e.g. carpet to laminate flooring), has increased the level of noise transmitted to the dwelling below – this is one of the most common reasons and increase in noise.
  • Changes have been made to the existing construction which has had a negative impact on the sound insulation
  • The original existing construction was never suitable to meet the insulation standards required of a separating wall or floor structure – in-line with Part E of Building Regulations.
  • The existing wall or floor components have deteriorated over time and are in need of replacement this may be because the wrong fixings have been used on the existing floors.
  • The upgrading of the existing windows to double and/or triple glazing has reduced external or background noise through the building façade, thus making neighbour noise more noticeable through separating walls and floors.
  • New cut outs in the existing wall to hide new cable for the wall mounted LCD TV’s is another popular reason for noise bridging through walls.

Other factors may have an impact on the overall noise levels, such as when new neighbours move in. Occupants may be more aware of sound insulation issues due to different living patterns between neighbours.

Upgrades or changes to the buildings structure, i.e. previous service works for water pipes, drainage and heating systems may have removed acoustic materials or interfered with acoustic isolation. This can lead to a wide disparity in performance between damaged and undamaged floors or walls.

In our experience, one of the most common triggers for noise complaints is the change of a room surface e.g. from carpet to wooden laminate flooring or floor tiles.  This can typically lead to a 10-20dB reduction in insulation performance. This can lead to neighbours below the apartment changing their assessment of impact noise from “acceptable” to “intolerable”. This can often lead to protracted and expensive legal issues especially if your lease doesn’t allow for hard surface upgrades.

Noise_Problems_Failed_Sound_Testing

People who live in detached houses or well-insulated attached houses may never have experienced hearing noise from neighbours, so when they move into a flat or attached dwelling they may feel that the level of sound insulation is poor, when infact it complies with Building Regulations Part E.

If you suspect that your noise levels are too high and you would like us to undertake sample sound insulation testing, or you would like us to investigate your noise complaints, please contact us now at: info@aptsountesting.co.uk  or phone us on 07775623464

Sound Testing In House Conversions

Sound Testing Results in House Conversions.

 Due to the housing shortage many houses are being converted into flats, which has resulted in a massive spike in noise complains amongst neighbours in such developments. Much of this rise in complaints are due to insufficient acoustic design at the start of the project, this means the dividing partitions are not being designed or constructed to comply with Part E of Building Regulations for Conversions.

 In our experience many of the sound insulation tests we undertake on refurbishment projects achieve 30-35dB for airborne sound, which is well below the required 43dB as stipulated in Part E. For impact sound testing, the figures are usually around 70dB which is well above the required 64dB, which is also a massive failure.

 Taking the above into account is it essential that the acoustic design is addressed right from the start of the refurbishment project.  The usual existing construction is 175mm joists with floorboards attached to the top and a single layer of plasterboard – as per the below detail:

Failed_sound_Testing_Due_to_existing_floor_Construction_

Upgrades or changes to the buildings structure, i.e. previous service works for water pipes, drainage and heating systems may have removed acoustic materials or interfered with acoustic isolation. This can lead to a wide disparity in performance between damaged and undamaged floors or walls.

 To overcome many of these issues we can visit site and undertake sample sound insulation testing through your property to establish the current noise levels. Once the noise levels have been established we can advise on acoustic upgrades to help you improve the sound insulation levels. it may be as simple as the installation of an acoustic resilient layer on the floor, or a minor wall upgrade.