Designing Enclosures for Room Integrity Testing

Designing Enclosures for Room Integrity Testing 

When designing server/data enclosures, it is the responsibility of the user and system suppliers to ensure that the enclosure and extinguishing system meet the design requirements as stated in ISO 15004.

Room-Integrity-Design

At the contract stage of the project, it is essential that responsibility for each of the enclosure requirements is made clear to all the relevant parties. In all cases it is important to consider the construction of the walls, floor and ceiling envelope when designing the enclosure containing one of your most important company asset(s) to be protected by the extinguishing system.  When designing the envelope for a protected enclosure there are  four critical factors to consider:

  1. Enclosure strength – to withstand pressure during gaseous suppressant discharge.
  2. Enclosure fire resistance – to withstand fire external to the enclosure.
  3. Enclosure pressure relief balance – to constrain the pressure differential across the enclosure structure to an acceptable level, by venting off excess enclosure gases during gaseous suppressant discharge.
  4. Enclosure air tightness – to aid retention of the agent after agent discharge.

In all cases the strength of an enclosure will be dependent on the materials of construction, the strength of fixings and attachments and the area they present to the load applied by the pressurised agent.

It is worth noting that Its been shown that once a fire – which has commenced externally to the protected area) breaks into the protected enclosure the agent will have little or no impact on asset protection. It is important therefore to maintain strict a‑minimum fire resisting enclosure of 60 min.

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At APT we provide room integrity testing for a wide variety of types and manufacturers of fire suppression systems, whether it is part of a system installation or annual inspection or intermediate post work testing

For further information on our room integrity testing services, please contact our technical manager Darren on 07775623464; or email 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.

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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.

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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.

Why do my Floors Squeak?

Why do my Floors Squeak?

We often receive complaints from clients in regards to their floors creaking. This is often because the Joists are often spaced too far apart, which can result in a reduction in floor stiffness. Over-notching of joists can also lead to a reduction in floor stiffness and also potential squeaking. Although the floors may pass the airborne and impact sound testing, however it won’t stop the squeaking of the floors under the extra load imposed by people walking above.

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Other problems may be down to the contractor using 12mm floor boarding instead of 18mm to the top of the joists, again this may allow the boards to move and squeak. It may also be down to the chipboard not sitting level across the joists, this may down to the  joists being installed at slightly the wrong level or a joist hanger may have been hit or come loose during the build. If the joist has been built into the wall the bearing could be unsatisfactory. it may be as simple as a missing joist, or cut edge unsupported or an over span on the joists.

  • Incorrect bridging of resilient layer by over-long screws/nails
  • Fixings connecting ceiling boards to resilient bars should not bridge to joists
  • Extra wide joist spacing that reduces floor stiffness
  • Platform floor resilient layers damaged by inserting pipes and services within the layers
  • Reduction in stiffness due to use of joist hangers
  • Ceiling boards not staggered
  • Over-notching of joists for services reduces floor stiffness
  • Incorrect omission of flanking strips at floor edge perimeters.

In most cases, due to the complexity of acoustical and noise problems along with an 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 compliance with Building Regulations Part E.

If you have a project that requires acoustic design advice and/or sound insulation testing, then please contact us at: info@aptsoundtesting.co.uk or phone me (Darren) on 07775623464.

Good Acoustic Design for Sound Testing

Good Acoustic Design for Sound Testing

To attain the standards stipulated within Building Regulations Part E, careful consideration should be shown to your buildings acoustic design  from the start of the project; however this requires different construction techniques and acoustic design detailing for new and build and conversion projects. With new build properties you have a blank canvas in terms of the overall design whereas conversions usually require you to work with the existing construction which can be quite difficult if the existing construction is not acoustically robust.

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To try and overcome the problems with attaining Part E for your conversion project, we now offer an acoustic design package, which contains the following elements:

  1. Sample Sound Testing – of the existing construction. This offers an accurate overview of the acoustic performance of the existing partitions; this enables us to offer a targeted acoustic design using the sound insulation performance of the existing construction.
  2. Acoustic Design Review – a full design review of the proposed developments party walls and floors taking into account the performance characteristics of the existing construction as well as the buildability and materiel cost of the acoustic upgrade.
  3. 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.
  4. Final Precompletion Sound Testing  – in compliance with Building Regulations Part E to help achieve building control sign off.

We have undertaken hundreds of design reviews around London and the South East with our clients achieving  a 100% pass rate where the acoustic review has been followed. If you would like some more information in regards to our acoustic services and/or sound testing services please visit our website at info@aptsoundtesting.co.uk, or contact us at: info@aptsoundtesting.co.uk or call me (Darren) direct on 07775623464.

 

Noise Damping to Improve Sound Testing

Noise Damping to Improve Sound Testing 

Noise damping is the most efficient and effective ways to control vibration and noise radiation at the source. Damping materials lessen this noise by turning the vibration into a low-grade heat. By using viscoelastic materials, it changes the resonant frequency of a substrate. By combining vibration damping materials and sound absorbers a composite acoustic construction can be achieved, that can control both airborne and structure borne noise – the final element for good soundproofing.

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It is worth noting that a  large number of manufacturers now produce a wide range of systems designed to improve sound insulation in homes and commercial buildings. In all instances, the effectiveness of these materials will vary depending on the situation in which they are installed. When choosing the acoustic product/s, detailed information on the likely sound insulation performance should be requested from the supplier. If you have an existing property you should check the existing construction of the dividing wall/floor partitions and work back from there. You are advised to give careful consideration to the data supplied by a manufacturer before using a proprietary product. it is also worth noting that the sound insulation value/s given for each product will be ‘best case’ as they have been tested in laboratory conditions and not on site – this is usually worse result by up to 3-5 dB) which may be the difference between a sound test pass or failure.

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Also when undertaking remedial work to improve the sound insulation, the acoustic materials are often quite heavy which may result in considerable weight being added to the structure of a property. Thus it is essential to check that the ceiling or floor joists can carry the increased loads satisfactorily.

So in a nutshell if you allow for the following four main elements of sound insulation on your acoustic partition design; Decoupling, Absorption, Mass and Damping, your development should pass the sound insulation test at the first attempt.

If you would like more information in regards to acoustic design and sound insulation testing, please contact us now at info@aptsoundtesting.co.uk or call Darren direct 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.

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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.

Sound Testing Services for New Dwellings

Sound Testing Services  for new dwellings

Sound Testing Services became mandatory in England & Wales in 2003, when Approved Document E was updated. Approved Document E requires new and converted to achieve a reasonable level of sound insulation between dwellings. The easiest way simplest way to comply with the requirements of Approved Document E; is to have on-site pre-completion sound insulation testing carried out on your project.

Many of our clients are clients are apprehensive prior to having to undertake pre-completion sound insulation tests.  This is often down to the fear of failure; however if the the acoustic design specification has been undertaken from the offset of the project and is closely followed during the construction phase then he chance of potential failure is greatly reduced.

sound testing equipment

Approved Document E requires a minimum of one ‘set’ of tests for every ten units in each group and/or sub group.  This is usually broken down to two airborne wall, two airborne floor and two impact sound tests. If you have a development of 25 houses, with five different sub-groups (5 units in each) then you would usually conduct 5 ‘sets’ of tests.  If no separating floors are available, i.e. in semi-detached or terraced houses, one set of tests would consist of two airborne tests of separating walls only.

If the precompletion test results do not satisfy the performance criteria of Approved Document E, then our test engineer will attempt to determine the possible causes of failure. This may be to do with construction detailing around services or at junctions, or simply, poor acoustic design. Once a specific reason for failure has been determined, we can then advise the client on remedial actions that can be undertaken.

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.

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

Poor Acoustic Design

Poor Acoustic Design 

Sound test failure is often down to poor acoustic design detailing during the design and construction phase of a project.

Sound test failure are often associated with poor acoustic design which allows noise flanking transmission through dividing floor and wall partitions. Unwanted noise travelling along flanking paths can make the building structure vibrate which causes the sound to radiate into your room. One simple cost effective solution is to build another wall or ceiling in front of the original, to offer extra isolation. For this upgrade to work you need to make sure that the independent wall or ceiling is not directly connected to the existing failed partition; so it provides isolation between materials.

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One of the main reasons for excessive noise flanking down to the use of lightweight blocks in the construction of the wall construction. Due to the lightweight mas of the inner wall it allows sound to transmit from dwelling to another, both vertically and horizontally. If a building has failed its sound testing, it is essential to establish if the problem is due to direct transmission, flanking transmission or a combination of both so that the most cost and time effective remedial treatment can be designed and applied to the failed partitions.

One way to reduce the chance of sound testing failures due to excessive noise flanking transmission is through a careful consideration to the acoustic design at the start of the project.  Unfortunately, by simply specifying high performance wall and floor partitions, it is no guarantee to adequate sound isolation and successful sound testing.

APT offer preconstruction design advice to help you achieve successful sound testing in London in-line with Building Regulations Part E. We also offer onsite inspection services to ensure that the sound insulation elements are being installed as per manufactures guild-lines, as its not use having a robust design if it not being installed properly on site.

If you require more information in regards to sound testing and/or acoustic design on your project please visit our site at www.aptsoundtesting.co.uk or contact us at info@aptsoundtesting.co.uk, or call me direct on 07775623464.

The two types of sound insulation testing through floors.

There are two distinct types of sound insulation testing through floors, they are:

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

In the event of  both types of sound – Airborne & Impact) are emitting excessive noise through the ceiling/floor, then there are some easy installations that should reduce the sound levels and improve your sound test results.

sound testing equipment

We also offer an acoustic design service which helps clients to pass the sound testing upon completion of the acoustic upgrade. By advising on a simple cost effective wall and/or floor upgrade, we are able to forward simple to follow acoustic design reviews, utilising our extensive knowledge of different materials and construction methods. Where our acoustic upgrades have been incorporated into the site construction, all the pre-completion sound tests have passed, ensuring compliance with Part E of Building Regulations.

Pre-completion sound testing has been a mandatory requirement since 2003 and all new build properties and conversions which were built after this date require 10% of each party wall/floor construction type to be tested. In is usual to test 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 study’s, kitchens and dining rooms.

We also carry out a large amount of sound tests in council/housing association blocks, where the residents are experiencing excess noise between the dividing wall and floor partitions.

We provide full UKAS accredited air and sound testing in London, using the latest Class 1 equipment, 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 or sound testing in London, please contact us now at info@aptsoundtesting.co.uk or call us on 07775623464.