The Pathway to Good Acoustic Design

The Pathway to Good Acoustic Design 

There are many important acoustic design considerations when designing for apartment blocks, which require both airborne wall and floor and impact floor testing. here are a few of the main considerations:

  • Ensure all penetrations are fully sealed where they terminate through floors and they are adequately boxed with acoustic quilt and two layers of plasterboard.
  • 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.

Sound_Testing_Flats

By simply constructing a good separating wall or floor this may not in itself provide sufficient sound insulation to comply with Building Regulations Part E as the junctions of each separating wall and/or floor with other parts of the building are as equally important. One of the main problems with partition failure is down to noise flanking, this can occur via construction components such as:

  • The internal partitions
  • The inner leaf of the external wall
  • The external wall cavities
  • The external façade or outer leaf
  • The roof structure
  • The foundations.

The overall design and construction system should therefore be considered and not just the separating wall or floor partitions.  Flanking sound 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.

architect drafting a house blueprint

architect drafting a house blueprint

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 Some 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.

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.

Acoustic Terminology M-S

Acoustic Terminology M-S

Our previous blog explained the  of acoustic terminology, this blog covers  M-S.

Mass

This is a physical quantity that expresses the amount of matter in a body. Walls and floors may be described in terms of the surface density (mass per unit area, kg/m2) of the wall face or the floor surface, which is the sum of the surface densities of each component of the construction. The density of materials is expressed as mass per unit volume, kg/m3, which can be provided via the core structure and linings such as in-situ concrete or solid dense block walls.

Mass per unit area (or surface density)

This is is expressed in terms of kilograms per square metre (kg/m2). This is often used to describe boards, panels, flooring and dry linings (see gypsum based board).

Resilience

This can reduce structural vibration transmission and still maintain material performance and overall dimensions, examples include floating floor treatments such as resilient battens or cradles, or resilient ceiling bars.

Resilient ceiling bars

This acoustic solution is generally metal based and vary in thickness from 11 mm to 30 mm. They are mounted perpendicular to the joist span direction and can increase both airborne and impact sound insulation. Care should be taken to ensure that the ceiling board fixings into the resilient bar do not come into contact with the joists and reduce the potential performance.

Resilient noggin

This is a small section of resilient ceiling bar which is used to assist in bracing non load bearing partitions.

Rw

This is a single-number quantity (weighted) which characterises the airborne sound insulation of a building element from measurements undertaken in a laboratory, in accordance with BS EN ISO 717-1: 1997

Sound Insulation Testing

Sound Insulation Testing is required near the end of a development to show that the performance of the party wall and floor partitions meet the standards as stipulated in Building Regulations Approved Document E. The testing methods for airborne and impact sound insulation is in full accordance with the suggested methods presented in BS EN ISO 140-parts 4 & 7: 1998.

Stiffness

This is can improve low frequency sound insulation, for example in floors, by reducing the potential for deflection or movement of the primary structure, therefore the correct spacing and depth of joists is important.

If your project requires some acoustic design input and/or sound insulation testing please don’t hesitate to contact us at info@aptsoundtesting.co.uk or call Darren direct on 07775623464 or visit our website at: www.aptsoundtesting.co.uk

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 in London

Acoustic Design Service in London.

If you have a property that has failed its sound testing in London, it may be down to number of reasons with the acoustic construction. To help our clients overcome this problem, we also offer our acoustic design service which helps clients to pass the sound testing upon completion of the acoustic upgrade. We can offer advice on cost effective wall and/or floor upgrades, also taking buildability and material cost into account. Our acoustic design reviews are easy to follow for the site construction staff.

Room-Integrity-Design

By utilising our extensive knowledge of different materials and construction methods, we have had no sound test failures where our acoustic upgrades have been incorporated into the site construction.

London Sound testing usually needs to be carried out between pairs of rooms separated by party walls and/or floors. Most sound tests are carried out between living rooms and bedrooms as these are classed as the two main habitable rooms; however, other rooms can be used if this is not possible such as studies, kitchens and dining rooms.

To help control noise issues APT Sound Testing can undertake UKAS accredited Part E sound testing in London and throughout the South East. Our sound test engineers carry all the latest class 1 acoustic equipment. We provide full UKAS accredited air and sound testing in London, so our clients can be sure that all testing is completed to a strict ISO quality controlled standard

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

Acoustic Terminology C-F

Acoustic Terminology C-F 

Our previous blog explained the A-B of acoustic terminology, this blog covers C-F.

Cavity stop

This is a proprietary product or material such as mineral wool (fibre) used to close the gap in a cavity wall.

Composite Resilient Batten

This is composed of a timber batten with a pre-bonded resilient material to provide isolation between the flooring surface layers and floor base.

Cradle/Saddle

This is an intermediate support system (with a resilient layer base, either pre-bonded or already integral) using levelling packer pieces to support a timber batten, isolating it from the floor base.

Decibel (dB)

This is the unit used for different acoustic quantities to indicate the level with

respect to a reference level.

Density (kg/m3)

This is the mass per unit volume, expressed in kilograms per cubic metre (kg/m3). Blockwork is commonly referred to by industry in terms of strength (in Newtons). However, it is the density that has the important role in terms of sound insulation.

Direct transmission refers to the path of either airborne or impact sound through elements of construction.

DnT,w

This is the weighted standardized level difference. A single-number quantity (weighted) which characterises the airborne sound insulation between two rooms, in accordance with BS EN ISO 717-1:1997

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.

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).

Room-Integrity-Design

If you need acoustic design advice and/or sound insulation testing please let us know. APT Sound Testing will ensure you will have direct contact with the allocated acoustician from the start of the process, through to the successful completion of the sound insulation testing.

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

Our Acoustic Services

Our Acoustic Services

APT Sound Testing offers a full turnkey solution for all your acoustic requirements to ensure compliance with Building Regulations Part E and achieve building control sign off for the acoustic elements of the project. This ensures your company receives professional advice every step of the way, with an on-going continual consideration of cost.

Our acoustic services consist of the following elements:

Sample Sound Insulation Testing

We visit site to undertake sample sound testing to the existing buildings walls and floors to check the sound insulation performance of the existing dividing partitions. Thereafter, once the sound levels have been established and targeted acoustic design can be undertaken to ensure compliance with Building Regulations Part E.

sound testing equipment

Acoustic Design Service

We can help develop the acoustic design of the project from the initial design scheme stage through to the precompletion sound testing. In particular we review the acoustic details to take into account the mass, isolation and absorption elements of the construction.

Site Survey Visits

We offer site survey visits which allow you (the client) and your contractor to feel confident about the outcome of testing at the end of the build. The site visits let us check that the installation teams are installing the acoustic materials as per manufacturers avoiding crucial onsite mistakes. You can often have a compliant design which still fails due to poor workmanship; the site survey visits negate the risk of sound test failure.

Acoustic_Site_Survey

Sound Test Failures

If your building fails the sound testing, we can use our experience in building construction and acoustics to firstly diagnose the reasons for the sound test failure and thereafter recommend a cost-effective solution to allow you to achieve building regulation compliance.

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.

Acoustic Design Service

Acoustic Design Service

The importance of good acoustic design and construction should not be under estimated. If a project fails its precompletion sound testing it may need costly remedial works to comply with Building Regulations Part E.

On new build developments we offer comprehensive acoustic design via coordination with the lead consultant. We can also visit site during the construction process to undertake a detailed site survey visit to check the onsite construction is as per the construction details – this is often good to ensure the relevant parties are fully aware of the installation detail required, which in turn may highlight possible ‘onsite’ construction problems.

Acoustic Design Service in London 

Acoustic_Site_Survey

On conversion projects we can visit site and undertake sample sound testing, this will evaluate the performance of the existing floor and wall partitions, which allows for targeted acoustic design as the acoustic performance of the dividing partitions may be already good –  especially if the buildings floors are constructed out of cast in situ concrete.

APT Sound Testing  provides a consultancy design service to Architects, Property Developers and Building Contractors. We specialise in helping small developers pass their sound testing to achieve Part E compliance for all types of project such as new build properties, blocks of flats and conversions.

Sound_Testing_Flats

Many of our clients have previously conveyed negative feedback that larger acoustic consultancies don’t understand small builder requirements and subsequently often produce complicated acoustic design detailing that are both difficult (in terms of build-ability) and very costly to undertake. We try to provide acoustic solutions that are cost effective and easy to construct, saving our clients time and money.

If you would like more information in regards to our acoustic design service and/or 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

 

Noise Complaints in Existing Apartment Blocks

Noise Complaints in Existing Apartment Blocks

Over the last few years we are noticing a rise in noise complaints in existing apartment blocks. There may be many reasons for this. Noise problems range from airborne noise transmission from voices TVs and music to footfall impact noise caused by high heels on wooden/tiled floors – it is usually the impact noise that is noticed most by the residents if the unit above has changed their floor finish from carpet to wood.

Excessive-Noise

In many cases even if the floor assembly has been designed and constructed to provide adequate airborne isolation, impact noise can still be a major problem. One of the main problems is if works to the floor finish have been undertaken, changing it from carpet to timber. Even if it passes the sound test, the perceivable rise in impact noise often leads to complaints, as carpet and underlay normally provides a good degree of impact sound isolation. Taking this into account it’s very important that impact isolation design, is taken into account before the installation of a hardwood and/or ceramic tile finish.

If you think you may have a problem with sound in your dwelling and/or you have encountered complaints from a neighbour due to changes you have made to the floor finish then please contact us now. Try to describe the noise problem in as much detail as possible. Describe the nature of the sounds, when and where you or your neighbour can hear it. Is it impact noise or airborne noise or a combination of both? The more information you can provide us, the quicker we can try to determine the nature of the problem and find a solution. It may be as simple as the installation of an acoustic resilient membrane to the floor.

Acoustic_Site_Survey

In our experience, if careful consideration is shown to the acoustic element of the floor upgrade, it should reduce the chance of complaints at a later stage, which will also avert costly legal battles at the end of the project and which often leads on to expensive remedial works.

We can come in prior to works commence and undertake a sample sound test of the existing floor partition, thereafter we can advise on the acoustic design of the floor. once the works have been completed we can then undertake a final precompletion sound test to show compliance with Building Regulations Part E.

If you are about to make changes to your apartment floor, and you require acoustic design advice, then please contact us now at: info@aptsoundtesting.co.uk  or phone me directly on 07775623464.

Sample Sound Testing

SAMPLE SOUND TESTING 

Sample sound testing is the cornerstone of acoustic design when it comes to the conversion of commercial buildings into residential developments. We can undertake sample sound testing to the existing buildings walls and floors to check the sound insulation performance of the existing dividing partitions. Thereafter, once the sound levels have been established and targeted acoustic design can be undertaken to ensure compliance with Building Regulations Part E.

Sound_Testing_Flats

We offer a proactive approach to acoustic design, onsite construction checks and sound testing. This ensures your company receives professional advice every step of the way, with an on-going continual consideration of cost. Our main acoustic services consist of the following.

Sample Sound Insulation Testing

We undertake sample sound testing to identify the sound levels for the existing partitions. Thereafter a more targeted acoustic design can be undertaken to the partitions saving time and money through the construction process.

Sample_Sound__Testing

Acoustic Consultancy  

We have considerable experience in all matters related to architectural acoustic design and detailing. We can help develop the initial acoustic design of the project from the initial design scheme stage, in particular acoustic isolation, and interior acoustics. We also use the latest Norsonic equipment analysers and sound sources for conventional and binaural acoustic measurements.

Site Visits

We offer site visits which allow you (the client) and your contractor to feel confident about the outcome of testing at the end of the build. The site visits let us check that the installation teams are installing the acoustic materials as per manufacturers avoiding crucial onsite mistakes. You can often have a compliant design which still fails due to poor workmanship; the site survey visits negate the risk of sound test failure.

Acoustic_Site_Survey

Precompletion Sound Insulation Testing

We undertake the final precompletion testing to ensure compliance with Building Regulations Part E and achieve building control sign off for the acoustic elements of the project.

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