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

Good Acoustic Design Considerations

Good Acoustic Design Considerations

In our experience careful consideration to acoustic design should be undertaken from the start of the project, if this process is followed it usually results in successful precompletion sound testing in compliance with Building Regulations Part E.

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

sound testing equipment

Here are some simple acoustic design tips:

  • Ensure all penetrations are fully sealed where they terminate through floors and they are adequately boxed with acoustic quilt and two layers of plasterboard.
  • Use resilient acoustic hangers within the ceiling design to provide isolation between materials.
  • Avoid the use of lightweight blocks in the inner envelope construction as sound will travel both vertically and horizontally from dwelling to dwelling.
  • 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.

In our experience by simply designing and constructing a good separating wall or floor it may not 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.

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 and lightweight materials have been used in the wall construction. If the acoustic consultant has not been made aware of the existing construction it may increase the chance of sound testing failures.

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 for London Projects

Acoustic Design Service for London Projects

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

architect drafting a house blueprint

architect drafting a house blueprint

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

The most common noise flanking pathways are as follows:

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

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

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

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

Sound Testing for Leasehold Agreements

Sound Testing for Leasehold Agreements

One of the main reasons for neighbour disputes is down to the fact that floor modifications may have taken place without the flat owner, first consulting his/her leasehold agreement. In many cases the lease agreement contains something similar to the following conditions:

Sound Testing through Floors

Part-E-Sound-Testing

‘If the tenant wants to change the floor construction within his dwelling he shall’:

  • Commission an independent acoustic consultant to carry out a pre installation test, design the new acoustic installation and carry out a post installation test and provide the results to the landlord’s surveyors for approval; and
  • Invite the Landlord’s surveyor to inspect the acoustic insulation before it is concealed; and
  • Accept that the Landlord, whilst granting this Licence, does not accept any responsibility for the design or performance of the insulation provided and that if any issues arise the Tenant will address these immediately. In the event of reasonable complaint being upheld by the Landlord or his agent concerning noise affecting other Tenants within The Building, the Tenant will arrange for carpeting (the provision of which shall be determined by the Landlord) to be positioned and maintained at the Tenant’s sole cost;

We offer a comprehensive acoustic service to let our clients comply with their leasehold agreements.

  • Pre-works Sound Testing of the existing construction. This offers an accurate overview of the acoustic performance of the existing floor partition/s prior to the commencement of construction works. It also enables us to offer a targeted acoustic design using the sound insulation performance of the existing construction.
  • Acoustic design review – once we have the performance figures from the sample sound testing have been established, we can forward a design that should improve the performance of the existing floor partition – even if you are changing the floor from a carpet to engineered timber floor finish!
  • Site Survey Visit – This allows us to check that the installation team is installing the acoustic materials as per manufacturer’s guidelines.
  • Final Precompletion Sound Testing in-line with Approved Document E. This provides an accurate overview of the acoustic performance of the upgraded partition/s, the results of which can be handed over to the relevant person for sign off.

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

Acoustic Design and Sound Testing

Acoustic Design and Sound Testing

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

Noise_Problems_Failed_Sound_Testing

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

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

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

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

Acoustic_Design_Service

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

 

Sound Testing to Office Conversions

Sound Testing to Office Conversions 

When it comes to refurbishment projects such as office block conversions or large houses subdivided into dwellings, we can undertake a sample sound test of the existing wall and floor construction. 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 targeted way to formulate a more cost effective and accurate acoustic  design as we know the sound insulation performance of the existing partitions.

sound testing equipment

The sound insulation levels required to pass Part E are usually 45dB for airborne wall and floors and 62dB for Impact Sound Testing on new build, however sometimes a higher target may be required in-line with the Code for Sustainable Homes; this is usually in defined in the following figures +3, 5 & 8dB, this means if its plus 5dB you will need to achieve 50dB for airborne and 57dB for impact sound testing.  Obviously if you need to comply with the Code for Sustainable Homes then special attention must be shown to the acoustic design from the offset to reduce the chance of sound testing failure.

architect drafting a house blueprint

architect drafting a house blueprint

The amount of sound testing you require depends on the size of the development. All new build properties and conversions require 10% of each party wall/floor construction type to be tested, i.e. if you have built a pair of semi-detached houses you would be required to undertake 2 airborne wall tests. If you have up to 10 flats you would require 1 x 6 pack, consisting of 2 airborne wall, 2 airborne floor & 2 Impact sound tests – known as a 6 pack)  However if you have 11 units this would rise to 12 Sound Tests or 2 x 6 pack. Also, if you have many different wall or floor types you will be required to undertake more tests to satisfy Building Regulations Part E.

There are many ways to improve the chances of passing your sound test at the first attempt, they are:

  • 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.

Due to the overwhelming variety of material designs and combinations due to varying constructions, it is impossible to cover all problems in a short article such as this; however in our experience if the acoustic design is taken into consideration from the offset of the project, then it usually results in a successful sound testing and compliance with Building Regulations Part E.

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

Sound Testing on London Developments

Sound Testing on London Developments 

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

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

sound_transmission_through_floors

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

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

Sound_Testing_Flats

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

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.