The Main Sound Proofing Elements

The main Sound Proofing Elements

Coupled Wall Construction

We often get asked ‘how can we improve our soundproofing on our development. The first thing to understand is the basic of soundproofing design and construction. If you understand the basics, you’ll have a more educated view point in regards to the way sound and vibration behaves within your new dwellings. Basically, we want to stop sound and vibration through the walls and floors of your development and one of the best ways of doing this is avoiding coupled wall construction. In general, we are trying to stop vibrations from getting to “your” side of the wall or ceiling.

The plate below shows a typical wall and noise problems associated with it. With this type of construction noise transference is a big problem. If there is even moderate levels of noise on one side of the wall the chances are you will hear it.

coupled_wall_construction

If you look at the red arrows in the above diagram it clearly shows how sound is conducted from one side of the wall to the other. As the wall elements are firmly fixed against each other, i.e. the plasterboard is rigidly connected to the timber, the vibration conducts straight through the whole wall construction.

If you look at the blue waves this indicates airborne transmission. The plasterboard is vibrating back and forth which produces a sound wave in the wall cavity. This, in turn, vibrates the plasterboard on the opposite side of the wall. the whole construction acts like a  huge diaphragm or like a large speaker with both sides of the wall vibrating in unison, which is not ideal.

Our next blog will explain how we can reduce noise transmission by decoupling the wall construction. if you would like more information on our sound testing or acoustic design services please contact us now at: info@aptsoundtesting.co.uk or call Darren direct on 07775623464.

Noise Problems in Refurbished Industrial Buildings

Noise Problems in Refurbished Industrial Buildings

We often get asked to undertake a series of sound test measurements to establish the acoustic performance of the wall of floors construction in existing buildings where the dwelling owners are concerned about excess noise.

In recent years the refurbishment of old industrial buildings into residential dwellings has become a very popular. Frequently the existing finishes of existing concrete, brick or wood Noise Problems in Refurbished Industrial Buildingsare left as the interior finish, supposedly to provide the “loft” type of décor. Such designs require even more acoustic design attention if sound privacy is to be achieved. Potential noise problems in refurbished industrial buildings can be quite challenging so buyers should insist that actual on-site sound insulation testing is undertaken to check the building has complied with the sound design performance criteria of Building Regulations Part E.

sound_transmission_through_floors

If you think you have a sound problem in your dwelling and are seeking help to resolve the problem, be sure to contact us and describe the problem in as much detail as possible. Describe the nature of the sounds, when and where you can hear it. Is it impact noise or airborne noise or a combination of both? If the unit is of recent construction you may need to procure a set of architectural drawings and mark-up which partitions noisiest. The more information you can provide us, the quicker we can try to determine the nature of the problem and subsequently find an acoustic solution for the partition/s.

We can also visit site and undertake sample testing on the dividing partitions. If the partitions fail the tests we can identify the main reasons for the sound test failures so targeted remedial treatments can be undertaken.

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.

 

Sound Transmission Though Windows

Sound Transmission Though Windows

One source of great annoyance is often due to sound transmission though windows, this can be down to a variety of factors. If the windows are operable types, the first thing to check is to see if the widows close properly against their seals and any weather stripping is continuous and in good order. If the window leaks air, then more often than not it will usually leak sound. If the window closes to form a tight seal and the weather-stripping seems adequate the next thing to check is the window frame.

Noise_Problems_Failed_Sound_Testing

Windows are frequently installed in to the wall opening with plastic shims to insure the unit is plumb and level. The space between the frame and the wall should be insulated and sealed before the window casings are installed. If this was not done correctly you can probably detect the sound leakage by placing your ear close to the frame and listening.

Usually double pane windows have poor noise-stopping capabilities. This may be overcome by installing a layer of lamination. Many manufacturers offer this service but it can be quite costly. Although double pane windows do stop a bit more noise than single pane windows it is still not very effective. In a noisy environment, you would hardly notice the difference.

Part of the problem is down to the construction of double pane windows; this is because the two pieces of glass are coupled within the same frame and vibrate together, similar to a tuning fork. Sound insulation, however, is increased markedly by using a double pane system and replacing air by argon between the panes.

In some cases the thickness of the glass maybe the problem in which case it may be necessary to install another layer of glass on the inside of the existing frame making sure that the additional pane of glass is well sealed into the opening.

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 us directly on 07775623464.

Ceiling and Wall Assemblies for Part E

Ceiling and Wall Assemblies for Part E 

In our experience ceiling and wall assemblies, can be the main pathways for the two main types of sound transmission. The first type is the airborne sound –  such as loud music) and the second is impact sound, such as footfalls on the floor above.

If the ceiling and wall assemblies have been designed and constructed to provide adequate airborne isolation, impact noise can still be a problem. If the finished floor surface has been designed to accommodate carpeting, the carpeting and under pad will normally provide a good degree of impact sound isolation. On the other hand, if the finished floor is floor is constructed in hardwood, stone or ceramic tile. Achieving good impact sound isolation requires much more attention at the design stage to prevent potential sound test failures.

sound_transmission_through_floors

One of the main misconceptions is sound simply passes through materials, this is not the case. Sound waves are form of energy that energises any material that the sound waves come in contact with. Thus sound energy that impacts on a wall for floor/ceiling assembly will cause the material to vibrate like a radio speaker; the energised material then becomes the transmitter of the sound energy.

Thinner, more lightweight building materials often hold the key to effective noise control, by using materials with different acoustical characteristics that will dissipate and diffuse the sound energy. Insulation in the cavity converts some of the energy in to heat while a resilient channel will help minimise the direct connection of the gypsum board from one side of the assembly to the other. Each material and its relationship to one another, produces small increases in sound isolation that in turn reduces the transmission of sound through the whole system and subsequently improves the sound insulation characteristics of the acoustic partitions.

I hope the above article helps to explain the importance material selection within acoustic design.  If you would like more information or some acoustic design advice on your project, please don’t hesitate to contact me on info@aptsoundtesting.net or call me on 07775623464.

Reducing Noise in Residential Buildings

Reducing Noise in Residential Buildings

We often get asked how noise can be reduced in residential buildings such as apartments or terrace houses. One of the most common problems is noise transmission through the floor and ceiling assemblies in flats and through the wall partitions in houses. The usual noise problems range from airborne noise transmission from voices TVs and music to footfall impact noise caused by high heels on wooden/tiled floors.

Noise_Problems_Failed_Sound_Testing

In most cases for newer residential units many of the problems could have been prevented in the first place, if more attention had been paid to noise control during the design and construction process.   If the acoustic design has not been taken into account from the off-set of the project, then it becomes far more problematic and costly if noise problems are discovered and the partitions fail the sound insulation testing during the per-completion testing.

If you are contemplating the purchase of a unit, do not be afraid to question the contractor and the real estate agents about the sound insulation results for the unit. Ask if any of the units failed during the precompletion testing. In some cases just because a sample of the units had been tested during prior to handover doesn’t mean unit has been sound tested.

If you are not happy with the sound insulation properties of your unit then you may have a case to demand corrective action at the expense of others. If you have a noise problem that is not resolved and you go to sell your unit, you may be compelled to reveal the deficiency to a prospective buyer which may have an impact on the selling price.

If you need acoustic advice on your project, please don’t hesitate to contact us no at: info@aptsoundtesting.co.uk or call me direct on 07775623464.

Sound Testing on Conversion Projects

Sound Testing on Conversion Projects

In our experience acoustic design and sound testing on conversion projects don’t need to be problematic. If you are currently in the process converting offices and/or houses info flats or ‘Rooms for Residential Use’, then its very important that the acoustic design is embraced from the start of the project.

Air Pressure Testing  have many years of experience in providing acoustic design and sound insulation testing in a comprehensive package designed to help you meet the legal requirements of Building Regulations Part E.

Acoustic Design Advice

As a  multi UKAS accredited company, you can be sure that all our services are undertaken to the highest laboratory standards. The types of projects that need to comply with Approved Document E for conversion projects or ‘Rooms for Residential Use’ are:

  1. House to flat conversions
  2. Commercial building to flat conversions.
  3. Hotels and hostels
  4. Boarding houses
  5. Halls of residence
  6. Residential homes

We can offer you the following services to help your development comply with Approved Document E:

  1. We review the architect’s drawings to check the required acoustic principles have been followed and meet the requirements of Approved Document E.
  2. We undertake a site visit and analyse the current state of building construction. And to check there are no site specific construction problems that may affect the acoustic performance of the building.
  3. We under take sample sound testing to check the sound insulation properties of the buildings existing floors and walls.
  4. We will provide you with a full and detailed acoustic design report that outlines which acoustic treatments taking into account the most cost and buildability.
  5. We will provide ongoing support and site visits to assist the builder/consultant to ensuring that the level of detail required is met and deal with any ongoing issues that may arise.
  6. We will undertake the final precompletion sound testing to achieve compliance with Approved Document E.

We’ve successfully guided our clients through hundreds of different conversion projects helping our clients achieve compliance with Approved Document E.

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

Airborne and Impact Sound Tests

Airborne and Impact Sound Tests

You are required to undertake two types of sound testing to comply with Building Regulations Part E, they are Airborne and Impact sound tests. Airborne sound tests are undertake on wall and floors and impact tests are undertaken on floor only.

To test the sound insulation properties of a floor or wall via airborne sound testing, you need to provide a sound source which consists of an amplifier and loud speaker is set up on one side of the wall or floor partition that is to be tested. We then turn the setting to turn on Pink noise. Pink noise sounds like the static that can be heard on a radio that is off station. Pink noise is used  because it is made up of a wall of sound that has a wide spectrum of frequencies. This provides an indication of sound insulation performance for a wide range of sounds that may be experienced within a dwelling from musical instruments to loud TV noise sources.

sound testing

The pink noise is measured in the room which contains the speaker or sound source using a Class 1 Norsonic sound level meter; thereafter the noise is measured on the other side of the wall or floor partition that is being tested. In layman’s terms the difference between these two levels is the amount of sound that is stopped by the sound insulating qualities if the wall or floor partition/s. The result is then corrected and adjusted depending on the echo or reverberation time within the receiving room, and any background noise such as builders work noise etc.

To test the impact sound insulation performance of a floor, a Norsonic tapping machine which consists of five small hammers that are dropped onto the floor to simulate foot fall, is placed on the floor. The resultant noise in the room below is measured with a Norsonic Class 1 sound level meter and the amount of noise that passes through the floor is the impact sound transmission level and is expressed as a single number. This result is then corrected and adjusted depending on the reverberation time of the rooms as well as any background noise to give the impact sound transmission result (LnT,w).

Impact Sound Testing

Both types of sound tests results are then compared to the performance criteria of Approved Document E, which stipulates that airborne sound needs to achieve 45dB for new build & 43dB for conversion projects. To achieve a pass for impact sound testing you need to achieve 62dB for new build & 64dB conversions.

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

Successful Sound Testing in London

Successful Sound Testing in London 

From the offset careful consideration should be shown to the acoustic design detailing for both conversion and new build projects if you are to achieve a successful sound testing in London at the first attempt.

For instance many of the dwellings in London consist of flats converted from large Victorian houses. At the time of the original build some 100 years ago, designing for sound insulation was not a consideration 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.

ACOUSTIC_DESIGN

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 and subsequently  from dwelling to dwelling. By adding isolation and  mass to the floors and wall construction compliance with Part E for conversion projects can be achieved.

To help our clients achieve successful sound testing we offer the following ‘3 step package’:

  1. Sample Sound Testing of the existing building. 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.
  2. Acoustic Design Review of the proposed developments party walls and floors to ensure acoustic details with be sufficient to pass Building Regulations Part E
  3. Site Survey Visits to check that the onsite construction is being undertaken in-line with manufacturer’s guidelines.

In our experience if the acoustic design is taken into consideration from the offset of the project, then it usually results in compliance with Building Regulations Part E.  In many cases sound test failure is down to poor acoustic design and poor workmanship, that is why we offer the 3 step process to achieve successful sound testing on your London project.

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 us directly on 07775623464.

The Two Types of Floor Noise

The Two Types of Floor Noise

Under Building Regulations Part E there are two distinct types of floor noise to consider; they are:

  • Airborne Noise (for example speech and music)
  • Impact Noise (for example footsteps directly on the floor above)

By utilising our extensive knowledge of different materials and construction Even if both types of sound appear to be are excessive through the ceiling/floor, then there are some easy acoustic design upgrades that should reduce the sound levels and improve your sound test results. By utilising our extensive knowledge of different materials and construction we can forward a simple, cost effective solution for wall and/or floor upgrade. Where our clients have followed our advice they have achieved a 100% success rate for sound insulation testing – ensuring compliance with Part E of Building Regulations.

noise_flanking

The sound testing procedure is quite simple and our engineer will be happy to explain this on site. Essentially, for party walls there is one type of sound insulation test which is airborne sound test and for compartment floors there are two types of sound insulation tests which are airborne and impact sound insulation tests. The airborne sound insulation test is carried out by means of a loudspeaker emitting a steady source of noise on one side of the partition (wall or floor) to be measured. The corresponding sound level is measured on the other side of the partition. Impact sound insulation tests are carried out by means of a tapping machine placed on the floor sample to be measured and the noise measured in the room or space below

All our engineers carry out the sound test measurements in full accordance with the measurement procedures of BS EN ISO 140-4:1998[3] for field measurements with a single figure DnTw and LnTw in accordance with BS EN ISO 717. As per the new regulations the Spectrum Adaptation Ctr which is a correction factor calculated from the measured DnT.w and the corresponding third octave band DnT values.  It uses a set of weighting levels in third octave bands derived from a road traffic noise spectrum.  It is applied to airborne test results and is measured in dB.

We can carry out final pre-completion sound testing on all new build or conversion projects throughout London. If you would like advice on your acoustic design or sound testing please contact us now at info@aptsoundtesting.co.uk or call me now on 07775623464.

Sound Testing Terminology (2 of 3)

Sound Testing Terminology (2 of 3)

Often confusion can arise from the large amount of ‘terms’ used in conjunction with acoustic design and sound insulation testing. To help with this we have made a list of the following terms for clarity – this is the second of three blogs:

Façade Testing  – This Standard – ISO 140-5:1998) specifies the testing methods to evaluate the sound insulation in buildings and building elements for facades. Three rounds of a proficiency testing scheme for airborne sound insulation measurements have been performed according to the methods specified in the standard for a whole facade by using an external loudspeaker as the noise source.

sound testing equipment

Flanking element (flanking wall) – This is any building element that contributes to the airborne sound or impact transmission between rooms in a building which is not the direct separating element (i.e. not the separating wall or separating floor).

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 skirting.

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.

We hope the above information in regards to Sound Testing Terminology has been helpful. If you would like more information in regards to acoustic design and sound testing services, please contact us at info@aptsoundtesting.co.uk or visit our website at: www.aptsoundtesting.co.uk