I Have Passed The Sound Testing So Why Do I Have Squeaking Floors

I Have Passed The Sound Testing So Why Do I Have Squeaking Floors

One potential problem with floors is that they can squeak after they have been installed. This is often down to the fact that Joists are often spaced too far apart which can result in a reduction in floor stiffness and complaints about footstep noise at low frequencies. Over-notching of joists can also lead to a reduction in floor stiffness and also potential squeaking. Although  the projects partitions may have passed impact sound tests, the annoying  squeaking sound may persist due to the extra loads imposed to the floor partition by people walking above.

Noise_Problems_Failed_Sound_Testing

To help with pass the impact sound test timber floors a resilient membrane is often incorporated into the overall floor design. This not only assists impact sound insulation (against footstep noise transference) but also reduces airborne sound transference.

Timber floating floors, must use a flanking strip to isolate the floorboards from the perimeter walls and skirting’s. If flanking strips are not fitted then footstep noise can easily enter the structure via walls etc. and subsequently flank into the adjacent dwellings. In the 1980s, mineral wool was used as a flanking strip but it was difficult to turn round at the floorboard edge. It was also prone to deterioration due to compression and movement under dynamic load. As a direct result of this, 5–10mm polyethylene flanking strips were incorporated into the acoustic design and construction, they are also easier to install and do not degrade over time to the same extent.

There are many reasons why floors may fail the sound testing, such as the use of incorrect mechanical fixing can reduce the insulation performance provided by floating floor treatments and resilient ceiling bars. Using very long screws will lead to bridging of the resilient layers and noise flanking. Inserting pipes or services within a platform floor can reduce the potential acoustic performance if they are not adequately boxed.  The placing pipes or cables under resilient battens can also bridge the resilient layer.

If you require more information about acoustic design and/or sound testing on your project,  please contact us now at info@aptsoundtesting.co.uk or call me direct 07775623464.

Careful Consideration to the Acoustic Design will help you pass your Sound Test

Careful Consideration to the Acoustic Design will help you pass your Sound Test

Careful consideration must be shown to the acoustic design from the start of every conversion project to avoid sound test failures. Most floor designs throughout the 1980s, encompassed the following construction details:

  • Floorboards (18–22mm thick)
  • Gypsum-based board
  • Mineral wool batt (80kg/m3)
  • Sub decking
  • 200-220mm joists
  • 100mm quilt insulation between the joists
  • One/Two layers of gypsum-based board for the ceiling

One the most common constructions used a combination of floorboard, gypsum board and mineral wool batt and was termed a “platform floor”. There is a wide range of batt densities. If the density is too low the floor surface is able to ‘bounce’ and deflect much more easily. If the density is too high then the floor may be too hard and impact sound is able to transmit more easily to the residential dwelling below resulting in sound test failure, so it was very difficult picking the correct materials.

ACOUSTIC_DESIGN

Often, even when resilient battens are used, continuous structural contact along the joist between the floor sub-deck and ceiling provides a strong path for sound transmission. If contact between the ceiling and the joists can be reduced, an increase in airborne and impact performance will be achieved.

One solution is to add another ceiling element to the overall construction. This can provide the extra isolation required to pass the sound testing in London.  This can be achieved by incorporate resilient metal bars which are connected to the underside of the joists and mounted perpendicular (90˚) to the joist direction. If plasterboard has already been tacked to the underside of the joists you can firstly add timber batten and then add the resilient bars, also mounted perpendicular (90˚ to the batten, thereafter 2 x 12.5mm layers of soundboard can be tacked to the underside of the resilient bar. Above the floor a resilient membrane can be used to reduce the chance of impact noise transmitting down to dwelling below.

If you require more information about acoustic design and/or sound testing on your project, please contact us now at info@aptsoundtesting.co.uk or call me direct on 07775623464.

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.

Minimising Noise Flanking Transmission to Pass Sound Tests

Minimising Noise Flanking Transmission to Pass Sound Testing

One way to reduce the chance of noise flanking transmission/s to pass the sound testing for Part E of Building Regulations is to carefully look at the acoustic details at the design phase of the project, as well as good planning and workmanship thereafter. Unfortunately, by simply specifying high performance wall and floor partitions between dwellings is no guarantee to a sound isolation and subsequently successful sound testing.

Sound travels along the path of least resistance between rooms, usually through any penetrations/air leaks or through rigid and poorly isolated connections in the structure itself, these routes are called noise flanking paths.

  • Wide gaps below doors provide a flanking noise pathway.
  • Air leakage around partition walls at the wall/ceilings junction.
  • Sound leaking through ‘lightweight’ hollow-core doors.
  • Through ductwork penetrations between two rooms or boiler cupboards placed back to back.
  • Fixtures & Outlets – Light Switches, Telephone Outlets, and Recessed Lighting Fixtures (if penetrations have been cut back to back with the opposite dwelling under test)
  • Poor sound isolation between floors, if subfloor wooden planking extend beneath the dividing floor partition and into an  adjoining dwelling this will form a sound flanking pathway.
  • Framing connections that include solid framing members passing between building areas such as oak beams where large old houses have ben subdivided.
  • Poor isolation to partition abutments to adjoining walls, ceilings, floors
  • Service penetrations behind back to back kitchens, such as soil stacks, waste and recessed pipework.
  • 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 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)
  • Dividing Floors – 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 Ceilings – Above and Through the Ceiling Space (where an adequate acoustic break has not been carried on through the ceiling void).
  • Recessed light fixtures that pass through the plasterboard and acoustic insulation.
  • The wrong fixings used during the installation of resilient channel systems, i.e. drywall screws that are too long that penetrate into the ceiling joists.
  • Window noise transmission due to poor performance glass etc.
  • Door noise transmission due to the inclusion of lightweight hollow core doors, with large gaps to the bottom of the door threshold.
  • On bathroom partitions, install drywall all the way to the floor before installing the bath and seal all plumbing penetrations through walls with a flexible sealant.

NoiseFlankingWall

If the wall/floor partitions have poor isolation and can greatly reduce the effectiveness of soundproofing efforts and can lead to sound test failures. Even if your construction allows for ‘robust’ sound insulation ratings, it will be rendered useless, if sound can pass easily through service penetrations in the walls and floors or through lightweight doors.

APT Sound Testing offers both pre & post construction design solutions to achieve the required sound isolation requirements of Part E of Building Regulations.

We offer an acoustic onsite inspection service to ensure that the sound insulation elements are being installed as per manufactures guide lines and the quality of the workmanship is consistent with ‘best practice’ noise control procedures and we have the technical experience to help identify and rectify your soundproofing or noise flanking problem/s.

If you would like more information in regards to sound testing, please contact us at: info@aptsoundtesting.co.uk or call us direct on 07775623464

Should I inform my Neighbours of the Sound Testing?

Should I inform my Neighbours of the Sound Testing?

Your neighbours will need to be contacted if access is required to their properties to complete the sound testing. Also as the sound levels produced during the test are very high it would be ‘neighbourly’ to inform the residents as they are likely to hear the test. If your project is a new build and/or a change of use and its built onto an existing property then chances are you will be required to undertake an airborne wall test. We recommend that you check this with your local building control officer prior to the testing so you can plan access to the neighbouring properties accordingly.
Can I Observe the Sound Testing?

sound testing equipment

APT Sound Testing will happily give you a brief demonstration and overview of the test, if so required; however, during the actual sound testing, we will need to follow stringent rules which restrict extra personnel within the test areas.
I want peace of mind that I’ll pass the sound testing

Poor Sound test results can occur for many reasons. The most common factor influencing acoustic performance is poor workmanship. Detailing is critical to maximising on site acoustic performance, especially in floor and wall isolation and appropriate party wall and floor construction. If inadequate provision for the isolation of materials is not undertaken

Should I inform my Neighbours of the Sound Testing? 

The Correct Site Conditions for Sound Testing

 The Correct Site Conditions for Sound Testing 

To undertake accurate sound testing, we require the site noise levels to be kept to a minimum. During the sound insulation testing, our equipment produces high levels of noise – between 100-110dB! However, to record accurate test measurements, relatively quiet conditions are required on site throughout the testing. Any site operatives working in the testing area will have to leave temporarily and any noisy works in the vicinity of the test areas including external site activity such as groundworks, drilling and banging will need to be halted. 

We also require full access to all the rooms being tested. We provide a full testing schedule within our quotation which will clearly identify suitable couplings of test rooms which may require access to adjoining neighbours dwellings to enable us to complete the sound testing

APT Sound Testing will try to schedule the sound testing with you at a time when noise can be controlled to achieve the best possible testing results. 

sound testing

What’s the Duration of the Sound Testing? 

The time taken to undertake sound testing varies from project to project as no site is exactly the same. Taking into account standard site conditions a set of tests on houses -two airborne walls will take one to two hours. A six pack of tests on flats – 2 airborne walls, two airborne floors and two impact tests will take between two to three hours. Throughout the sound testing, we will require full free uninterrupted access to the units/rooms in all test areas. 

If you require more information on sound testing, please contact us now at info@aptsoundtesting.co.uk or phone 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