Taff Vale Re-Development Pontypridd Stage 3 Building ... · dated 6th January 2017, and Hydrock’s Stage 3 MEP Interim Report dated May 2017. This assessment will be used to inform

Hunter Acoustics is the trading name of Hunter Acoustics Ltd Registered Office: Henstaff Court Business Centre, Llantrisant Road, Cardiff CF72 8NG Registered Number: 4587925

Taff Vale Re-Development Pontypridd

Stage 3 Building Services Review Report

4366/BS1

11th May 2017

For: Darnton B3 5 Callaghan Square

Cardiff CF10 5BT

Henstaff Court Business Centre Llantrisant Road, Pontyclun

CARDIFF CF72 8NG

Tel: 02920 891020

Email: [email protected]

mailto:[email protected]

Project: Taff Vale Re-Development, Pontypridd Hunter Acoustics

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Contents

1.0 Introduction ............................................................................................................ 3

2.0 BREEAM Criteria ................................................................................................... 4

2.1 Internal Ambient Noise Levels .............................................................................. 4

2.2 Atmospheric Side Plant Noise Emissions ............................................................. 4

2.2.1 Tenancy Agreement wording .......................................................................... 5

3.0 Building Services Roomside Noise Control ........................................................... 5

3.1 Plantroom Structures ............................................................................................ 5

3.2 Ceiling Void Unit (FCU/VRF) Design Guide Limiting Sound Power Levels ........... 5

3.3 Duct/Pipework and Electrical Services Penetration Details .................................. 7

3.4 Transfer Grilles & Cross Ventilators to Meeting Rooms ........................................ 7

4.0 Building Services - General ................................................................................... 8

4.1 Air Handling Units/Cased Fans ............................................................................. 8

4.2 Builderswork Shafts .............................................................................................. 8

4.3 Noisier Plant (Chillers/compressors/Generators/CHP/Cold Water booster) ......... 8

4.4 Vibration Isolation ................................................................................................. 9

4.5 Regenerated Noise ............................................................................................... 9

4.6 SVP’s & Syphonic Drainage ................................................................................. 9

4.7 Roof Plant ............................................................................................................. 9

4.8 Lifts ....................................................................................................................... 9

5.0 Roof ..................................................................................................................... 10

5.1 Top Floor Library & Fitness Areas. .................................................................... 10

6.0 Conclusion ........................................................................................................... 11

Appendix A: Acoustic Terminology ................................................................................ 12

Appendix B: Drawings ................................................................................................... 12

Appendix C: Penetration Details ................................................................................... 13

Appendix D - Outline Specification for Acoustic Hardware ............................................ 15


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1.0 Introduction

This report gives stage 3 advice for services plant acoustic considerations on the 3 buildings that make up the Taff Vale Re-Development. The assessment includes/refers to results of earlier environmental noise survey report dated 6th January 2017, and Hydrock’s Stage 3 MEP Interim Report dated May 2017. This assessment will be used to inform the architectural and building services acoustic design, which is to be to the latest BREEAM standards. Acoustic terminology is explained in Appendix A. The following is taken from the introduction to Hyder’s Stage 3 report; The proposed new development will consist of three buildings, a shared basement and associated public realm works. A brief description of each building is provided below: 1.1.1 Building A A proposed 5 storey (ground to 4th floor) office building with roof top plant area. Building A currently has no pre-determined tenant and will be developed to a Cat A level of fit out and offered for letting on the open market. A restaurant space is proposed at the eastern end of the building at ground floor / basement. A small café / restaurant A3 facility will be provided at the western end of the building at ground floor. 1.1.2 Building B A proposed 5 storey (ground to 4th floor) office building with roof top plant area. Building B currently has no pre-determined tenant and will be developed to a Cat A level of fit out and offered for letting on the open market. A small café / restaurant will be provided at the western end of the building at ground floor. 1.1.3 Building C A proposed 3 storey (ground to 2nd floor) mixed use building with RCTCBC ‘one for all’ space and cafés at ground floor, a public library at ground and first floor (with double height section at first floor) and a public gym at first and second floor (consisting of a fitness suite, spin room and changing facilities). 1.1.4 Basement A shared basement spanning the length of Buildings A, B and C will be provided for parking, storage and plant areas. The basement will be inaccessible to the public. The majority of the parking will be provided for use of the Buildings A/B tenants, with limited disabled parking provided for staff of Building C. 1.1.5 Public Realm The scheme proposes two new streets running perpendicular to Taff Street and a new public riverside ‘plateau’ between Taff Street and the Gas Road car park. Another pedestrian connection is proposed to Bridge Street. The new streets shall be high quality public spaces for access, general amenity and future seasonal market type facilities.


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2.0 BREEAM Criteria

2.1 Internal Ambient Noise Levels The following internal noise criteria are proposed, based on BS8233 2014 guidance;

2.2 Atmospheric Side Plant Noise Emissions Referring to background LA90 levels measured during our noise survey the following overall environmental noise limits are proposed at the closest residential receivers, understood to be flats above commercial units at 36 & 37 Taff Street. These limits are based on requirements of BREEAM Pol 5;

Daytime (0800-1800hrs) 45 dB(A) LAeq

Daytime Extended (0700-2300hrs) 45 dB(A) LAeq

Night (2300-0700hrs) 40 dB(A) LAeq The above limits shall be met at the closest neighbouring residential façade with all plant operating normally, allowing for additive effects of services plant serving buildings A, B & C combined, and therefore a suitably qualified acoustic consultant (MIOA and/or ANC member) shall be employed to assess overall emissions. The above should be confirmed acceptable with the local planners/EHO. A 45dB(A) @ 1m upper limit shall also apply for ground level intakes/discharges/plant to control noise levels to Public Realm areas.

Description

Noise Rating 'NR'

Criterion

Open Plan Offices (including spec' offices) NR38

Gym/Fitness NR40

Gym/Fitness Offices NR38

Multi-purpose area NR35-40

Library & Exhibition Space NR35

Training Rooms NR35

Consulting & Appointment Rooms NR38

Café NR40

Community Room NR35

Managers Offices NR35

Meeting Rooms NR35

Toilets NR45

Ancilliary (corridors/stairwells/Staff

/Changing Rooms) NR40-45


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2.2.1 Tenancy Agreement wording We would recommend the following limits are included in tenancy agreements; The tenant shall ensure their plant meets the following noise criteria; Roomside (in adjacent Tenancies): NR25 Atmospheric side

Daytime (0800-1800hrs) 35 dB(A) LAeq

Daytime Extended (0700-2300hrs) 35 dB(A) LAeq

Night (2300-0700hrs) 30 dB(A) LAeq

The above limits shall be met at the closest neighbouring residential façade with all plant operating normally. These limits have been set lower than the overall limits for the development to allow for additive effects of services plant serving different tenancies. A suitably qualified acoustic consultant (MIOA and/or ANC member) should be employed to assess airborne and structureborne noise levels roomside and atmospheric side. A 45dB(A) @ 1m upper limit shall also apply for ground level intakes/discharges/plant to control noise levels to Public Realm areas.

3.0 Building Services Roomside Noise Control

Roomside/Internal noise criteria are quoted in section 2.0 of this report.

3.1 Plantroom Structures

Initial design guide : Basement Plantroom Walls: Rw45 Typically 100mm dense concrete block (1800kg/m3) walls

Basement Plantroom Ceiling : Rw50 150mm profiled concrete deck (250kg/m2) with raised access floor above.

Roof Deck below Condenser Plant : Rw50 Typically 150mm profiled concrete deck (250kg/m2)

3.2 Ceiling Void Unit (FCU/VRF) Design Guide Limiting Sound Power Levels

Table 4366/T1 shows preliminary limiting sound power levels calculated as a design guide for ceiling void unit selection/modification to the various quoted areas. Generally the figures assume a Dncw35 Class A sound absorptive lay-in grid acoustic ceiling below the units, however we have quoted figures with no ceiling present for the top floor Fitness and Library areas of building C. We would warn against relying on manufacturer’s quoted NR or dB(A) figures for ceiling void units, they tend to be very optimistic (10dB+).


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Table 4366/T1 : Fan Coil/VRF Unit Limiting Sound Power Levels

Location Limiting Lw (dB re 1 x 10^-12Watts) @ Octave Band Centre Frequency (Hz)

125 250 500 1k 2k 4k

Buildings A & B Ceiling Void Fan Coil/VRF/MVHR Units

Open Plan & Spec' Office Areas (NR38 - Dncw35 Class A

suspended acoustic ceiling)

In-duct to discharge 59 47 39 34 31 29Casing radiated (including open Inlet if applicable) 54 48 46 45 43 41

Entrance Lobby/Reception Areas (NR40 - Dncw35 Class A


In-duct to discharge 59 47 39 34 31 29

Casing radiated (including open Inlet) 54 48 46 45 43 41

Building C Fan Coil Units

Fitness Area (NR40 - No suspended ceiling)


Casing radiated (including open Inlet)* 55 48 44 42 39 37

Entrance Lobby/Reception Areas (NR40 - Dncw35 Class A




Meeting/Training Rooms including Reference &

IT/Education (NR35 - Dncw35 Class A suspended acoustic

ceiling )



Cellular Offices (NR35 - Dncw35 Class A suspended acoustic

ceiling)



Community Room (NR38 - Dncw35 Class A suspended

acoustic ceiling)


Casing radiated (including open Inlet if applicable) 54 48 46 45 43 41

Cellular Offices (NR38 - Dncw35 Class A suspended acoustic

ceiling) ( adjacent to Gym/Fitness)



Library Consulting & Appointment Rooms (NR38 - Dncw35

Class A suspended acoustic ceiling)


Casing radiated (including open Inlet)* 54 48 46 45 43 41

*Locate unit in ceiling void of main Library/Exhibition Space and duct in over door.

Library (NR35 - Dncw35 Class A suspended acoustic ceiling

present)



Library (NR35 - No Ceiling)



The succesful tenderer shall provide independent laboratory test figures for

their units at the proposed duties confirming the limiting Lw's are met.

Test data shall be to BS 4856-4: 1997 or equivalent.


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The tighter figures for Buildings A & B reflect the increased number of ceiling void units (local MVHR and Recirculating FCUs) compared with the proposed Building C more conventional FCU system. Where common services serve male/female/disabled WCs include acoustically lined flexibles onto grilles 1.0m long GLC acoustically lined flex or equivalent. Services to consulting/appointment/meeting rooms and cellular offices might also use lined flex to terminal grilles for cross-talk control but these systems will need to be reviewed once layouts are confirmed. NB: acoustic flex is quoted as having relatively high insertion losses, however this in part is due to them allowing sound energy to break-out through the duct wall into the ceiling void (and therefore potentially down through the ceiling into the critical space), so the overall benefit should not be over-estimated. These figures are to checked/revised once we receive detailed services design layouts, and are included for initial plant selection/budgetary guidance at this stage.

3.3 Duct/Pipework and Electrical Services Penetration Details In order to maintain acoustic separation between critical areas, mechanical and electrical services shall be routed along corridors/ in open plan areas with branches off into the critical spaces over/adjacent to the access door. Do not route services through critical separating partitions. Penetration seal detailing is critical - three examples are attached to this report in Appendix C covering cable trays and duct/pipework in lightweight/stud partitions.

3.4 Transfer Grilles & Cross Ventilators to Meeting Rooms

Transfer Grilles and Cross Ventilators shall not be used to critical areas as they compromise acoustic separation/privacy.


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4.0 Building Services - General

4.1 Air Handling Units/Cased Fans

‘shall have double skin casings providing the following minimum sound reduction performance; Octave Band Frequency (Hz) 125 250 500 1K 2K 4K Minimum SRI of AHU Casings 14 14 24 25 25 25 (dB : BSENISO140 or equivalent) This specification applies to all sides of the enclosure (including roof, sides and floor). At this preliminary stage allow for roomside and atmospheric side attenuators on fan systems, built into the AHU sections to control break-out as well as in-duct noise levels. .A minimum 300mm plenum shall be left between louvers and atmospheric silencers. Appendix D details our Outline Specification for Acoustic Hardware used on this project. Attenuators shall also meet these requirements.

4.2 Builderswork Shafts

It is preferred that builderswork shafts carrying ductwork from plantrooms to conditioned areas are not compromised by the inclusion of access doors in the critical conditioned areas. Where this is necessary, solid core access doors (28kg/m2mass per unit area) shall be used with rebated perimeter neoprene seals.

4.3 Noisier Plant (Chillers/compressors/Generators/CHP/Cold Water booster)

Please confirm location of any external chillers, compressors, stand-by generators, CHPs and/or cold water booster sets as early as possible in the programme. The basement CHP should be designed/selected to meet a maximum 65dB(A) @ 1m free-field with a view to avoiding additional plantroom treatments. Please confirm location of CHP plantroom, and whether fresh air louvres are required to the CHP and/or cold water booster plantroom(s).


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4.4 Vibration Isolation

Where internal mounts are specified on AHU/cased fans, neoprene pads/mat shall be included below the casing - 2mm (nom) deflection.

Ductwork flexible connections shall be constructed of sound barrier mat (5kg/m2), a minimum 75mm long and no offset in order to avoid turbulence. Restrained spring hangers and mounts shall be used on all fluid filled plant, where varying load conditions may occur, in order to avoid damage when systems are drained. Reliance on flexible connectors as a sole means of isolating pipework is not recommended. All pipework connected to pumps and chillers should be supported by resilient hangers/mounts. The type and static deflections of the mounts are selected to be compatible with those selected for the associated plant. All vibration isolation hardware must meet the requirements of the 'Outline Specification for Acoustic Hardware ' - attached.

4.5 Regenerated Noise

The HVCA and CIBSE guides give general guidance on duct/pipework design and insulation. Further guidance on 'good practice' including maximum air velocities and damper settings is included in the Outline Specification For Acoustic Hardware - Appendix 1. Terminal control dampers should be used for fine trimming only.

4.6 SVP’s & Syphonic Drainage

Internal syphonic drainage soil and waste pipes shall be enclosed in 2 x 15mm plasterboard box section on an independent frame with 25mm mineral wool wrapped around the pipe, unless already located within an equivalent riser shaft. Please forward noise data for any symphonic drainage systems if available.

4.7 Roof Plant

Avoid mounting plant on lightweight roof structures to avoid drumming. Chillers should be mounted over non-critical areas as far as practical to avoid excessive slab requirements.

4.8 Lifts

Low-noise lifts should be used, including a volume limiter on lift announcements as these frequently cause annoyance. Lift installation shall be fitted with adequate vibration isolation to control transmission of structure-borne noise.

Include masonry shaft with independent wall lining system to critical adjacencies including community & reference rooms (2 x 12.5mm acoustic plasterboard on 50mm stud spaced 20mm off masonry shaft, with 50mm mineral wool in cavity).


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5.0 Roof

The following Roof guidance details are taken from our updated Building C Acoustic Specification Report 4366/AS1 – Building C – Rev 1 dated 10/5/17.

Minimum airborne sound insulation performance: 45dB Rw

Maximum rain noise sound intensity: 50dB LIA

The successful roof supplier shall provide independent laboratory test data confirming the above limits are met

5.1 Top Floor Library & Fitness Areas.

Please note there is no suspended ceiling proposed in the Library and Fitness Areas.

We would recommend considering a sound absorptive finish to the underside of the roof in Building C where no suspended ceiling is proposed (Fitness Areas and top floor of Library) – typically a suitably faced mineral wool behind perforated timber/plasterboard finish between the Glulam Beams (as used on Cardiff Library).

Alternatively, sound absorptive rafts can be included (often as part of a suspended lighting raft system) – the supplier should be able to give an estimate of number/area to meet reverberation time criteria quoted in section 3.1 of our Building C acoustic specification report. It may be necessary to include some wall sound absorptive panels in addition to the ceiling/raft treatments in high Library spaces.


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6.0 Conclusion

This preliminary Building Services assessment has been based on assumed services layouts referring to the Hyder’s Stage 3 Report dated May 2017. A detailed building services review will be carried out as soon as the detailed services design layouts and plant information is available. Information in this report is therefore for initial design/budgetary guidance. Prepared by:

David Hunter Checked by: BSc(Hons), MSc, MIOA

Hunter Acoustics

Paul McGrath BSc(Hons) MIOA

Hunter Acoustics


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Appendix A: Acoustic Terminology

Human response to noise depends on a number of factors including; loudness, frequency content, and variations in level with time. Various frequency weightings and statistical indices have been developed in order to objectively quantify 'annoyance'. The following units have been used in this report:

Leq: The equivalent continuous sound level is a notional steady state level which over

a quoted time period would have the same acoustic energy content as the actual fluctuating noise measured over that period.

LArTr : ‘Rating Level’ (BS4142): The LAeq noise level +5dB adjustment for plant noise

characteristic; or BS7445: +5dB adjustment (daytime), +3dB adjustment night-time.

DnT,w: This indicates the minimum weighted standardised level difference across a

separating construction. It is normalised to the reference receiving room reverberation time “To = 0.5s“.

Rw : The weighted sound reduction index of a construction element is the sound

reduction index obtained in a laboratory meeting the requirements of relevant standards. It is measured in the absence of flanking paths.

NR: Noise Rating – a method for assigning a single number rating to any noise

spectrum. NR ≈ dB(A) -6

Appendix B: Drawings

This preliminary assessment has been based on assumed services layouts on architectural floor plans/sections, referring to the Hyder’s Stage 3 Report dated May 2017. A detailed building services review will be carried out as soon as the detailed services design layouts and plant information is available. Information in this report is therefore for initial design/budgetary guidance only.


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Appendix C: Penetration Details

Figure C.1 : Cable Tray Penetration

Figure C.2 : Duct/Pipe Penetration in Lightweight/Stud Wall


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Figure C.3 : Duct/Pipe Penetration Detail through concrete


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Appendix D - Outline Specification for Acoustic Hardware

A. Silencers

A.1 Performance In order to assist system design, silencer sizes are shown which are representative of the cross-sectional area and length expected for the performance requirement, with due reference to the proposed duct dimensions. Silencers shall be located at least two duct dimensions from bends/dampers/fans in order to avoid excessive pressure drops and associated re-generated noise. Manufacturer’s insertion loss performance data shall be in accordance with BS 4718: 1971, and specified at the proposed operating conditions (including temperature). Manufacturers quoted pressure drop through each silencer shall be derived from test data in accordance with BS 4718: 1971, and specified at the proposed operating conditions. Regenerated noise levels (125 Hz - 4 kHz) shall also be included for each silencer under the proposed operating conditions.

A.2 Construction Mineral wool or glass fibre infill shall be inert, vermin proof, rot proof, non-hygroscopic and non-combustible. Fibres used shall be of a diameter greater than 3 microns and length greater than 200 microns. Silencer casings shall be in accordance with current H.V.C.A specifications in terms of thickness and seams. Splitters in rectangular silencers 900mm or longer shall be bull nosed at both ends. Splitters shall consist of 48Kg/m3 (minimum) mineral wool with glass fibre tissue facing, retained behind perforated galvanized sheet steel in order to prevent fibres passing into the air stream. Silencers shall have half width splitters fitted to each side wall. Splitters shall be normally vertical however it is the supplier’s responsibility to ensure correct orientation for adjacent duct geometry. Horizontal splitters shall be stiffened and normally limited to 900mm module lengths. Circular silencers shall incorporate acoustic medium as specified above for rectangular systems, retained by perforated metal or alternative approved membrane. High temperature applications such as diesel/turbine exhausts, boiler flues etc shall have suitable gauged steel casings, with design allowance for thermal expansion/shock. The mineral/glass wool infill shall be packed to at least 96kg/m3, faced with glass fibre cloth behind a perforated metal casing. Very high temperature systems may use steel wool (or equivalent) infill. Silencers shall be delivered to site with blocked ends in order to prevent debris damaging the splitter facings.


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B. Acoustic Louvres

Acoustic louvres shall provide insertion losses under operating conditions not less than that specified on the relevant schedule. The static pressure loss under maximum duty shall not exceed that quoted on the schedule. The louvre design shall prevent ingress of rain under normal meteorological conditions. The blades shall consist of 60-100kg/m3 mineral wool with glass fibre tissue facing, retained at the lower blade face by perforated galvanized mild steel or aluminium (to match the frame). All gaps between the perimeter of the louvre and wall/duct shall be sealed using heavy grout and/or non hardening mastic.

C. Plant Room Acoustic Lining

Where specified, shall consist of 64kg/m3 mineral wool slabs bagged in glass cloth, retained behind either perforated metal or chicken wire.

D. Vibration Isolator Mounts

The various isolator mounts discussed below are headed by a description, as used on the AV schedules.

D.1 Performance Mounts shall provide the static deflection shown in the AV schedules. It is the supplier’s responsibility to select mounts allowing for load distribution and/or torque reaction in order to ensure the quoted deflection is achieved on all mounts under operating conditions. It is the supplier's responsibility to ensure all mounts are suitable for the environmental conditions on site, in particular for externally mounted plant.

D.2 Caged Springs Shall incorporate a telescopic top and bottom housing (making up the 'cage') enclosing one or more helical steel springs. Shall incorporate a levelling device and allow visual inspection. Fully enclosed springs should not be used. All nuts/bolts used to adjust mounts shall incorporate a locking mechanism. Shall have a minimum 50% overload capacity before becoming coil bound Shall incorporate a neoprene pad 'noise break' at the base plate, to attenuate high frequency energy passing through the springs Where indicated on the AV schedule (code: #), shall incorporate a restraining device to prevent excessive movement on the mounts, for example when the system is drained for maintenance. However, any restraining device must not compromise the performance of the mount.

D.3 Open Springs As for D.2 above, excluding the telescopic 'cage'


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D.4 Neoprene Mounts Shall be colour co-ordinated or otherwise marked to confirm individual stiffness/capacity. Shall incorporate steel top and base plates embedded in oil resistant neoprene. Shall be capable of being fitted with a levelling device.

D.5 Spring Hangers Shall consist of one or more caged helical springs. Shall allow lateral movement of at least 15°.

D.6 Neoprene Hangers Shall incorporate a neoprene in shear element as described in D.4 above. Shall allow lateral movement of at least 15°.

D.7 Plant Bases A.V. Rails Shall comprise rigid steel beams, to avoid excessive strain in the plant. Shall include height saving brackets. Steel Frame Plant Base Shall comprise a rigid welded steel frame, to avoid excessive strain in the plant. The frame depth shall be not less than 0.1 x its longest dimension or 150mm. Shall include height saving brackets. Concrete Inertia Base (For Steel Springs)

Shall consist of concrete (2300kg/m3) poured into an all welded steel framework, not less than 0.083x the longest dimension or 100mm. The framework shall be blanked off, and the concrete poured over steel reinforcing rods, located 35mm above the bottom. Shall be of sufficient size to provide support for all elements of the plant, including suction/discharge elbows on centrifugal pumps. Concrete Inertia Base (For Neoprene Mounts) Shall be cast onto a permanent bottom shuttering and supported on the quoted mounts/pads. Shall be of sufficient size to provide support for all elements of the plant, including suction/discharge elbows on centrifugal pumps.


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E. Re-Generated Noise - Design Parameters

E.1 Airflow Noise in Ducted Systems

General parameters for duct & pipe work design, fabrication and insulation are given in HVCA and IHVE codes of practice. The following represents a list of 'good practice'. i) 90° bends or bifurcations shall be either radiused or include equally spaced short-chord

turning vanes. ii) Branches shall be coned or fitted with boots. iii) Transitions shall be as gradual as possible, preferably with one pair of sides remaining

parallel. iv) Aspect ratios for main/branch rectangular ducts shall not exceed 3: 1 otherwise acoustic

lagging may be required. E.1.1 Maximum duct velocities:

E.1.2 Volume Control Dampers

The following table quotes design limits for opposed blade volume control dampers against the relevant internal noise criteria, based on the product: Velocity (m/s) x Pressure Drop (Pa)

Remedial treatment may be required where the above figures are not met - refer to acoustic consultant.

Damper Location >NR50 NR45 NR40 NR35 NR30

In Duct 3600 2000 1100 600 350Stub duct (above ceiling) 1250 680 380 200 110@ Grille/Diffuser 360 200 110 60 40


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E.1.3 Fan Coil Unit/VAV Systems Manufacturer’s often quote overall NR or dB(A) sound pressure levels for their units. In our experience they are often quoted at 3m distance ‘free field’. This can result in them being around 10dB optimistic compared with the typical site situation - 1.5m receiver distance in a cellular office or multiple units serving an open plan area/meeting rooms. Suppliers should be made aware at the outset that independent test data (in duct and casing radiated) will be required for comparison with design requirements/limiting spectra - casing radiated and in duct to discharge - measured to BS 4856 (or approved field test).

E.2 Piped Services

In order to avoid flow re-generated noise problems, friction losses should not exceed 280Pa/m in pipes of 12-75mm diameter.

F. Liability

All selections shall comply with the above specification. Any variation may result in the tender being ignored, or liability for subsequent remedial/replacement and consequential costs, unless variations are accepted in writing by the acoustic consultant or client.

The buyer should check manufacturer's sale conditions do not contravene this specification.

Documents

Taff Vale Re-Development Pontypridd Stage 3 Building ... · dated 6th January 2017, and Hydrock’s Stage 3 MEP Interim Report dated May 2017. This assessment will be used to inform