Acoustic Louvres- Brochure

Acoustic Louvres Type LAAC 30 & LAAC 15NOISE CONTROLProduct Data Sheet No. 108/03ConstructionStandard EMTEC LAAC 15 and LAAC 30 Acoustic Louvres aremanufactured from high quality galvanized sheet steel. Thelouvre frame and the upper surface of the blades are formedfrom plain sheet and the under side of the blades fromperforated sheet. The acoustic media contained within thelouvre blades is inert, non-flammable mineral wool and wherea birdscreen is fitted to the rear face of the louvre this is made from galvanized steel wire mesh having 12mm spacings.EMTEC LAAC 15 and LAAC 30 Acoustic Louvres can besupplied in aluminium, stainless steel, plastic coated steel orgalvanized steel polyester powder coated to compliment thearchitectural design of the final installation.External or internal angle flanges can be supplied to fixlouvres into structural openings and are normallymanufactured from the same material as the louvre itself.Both types of acoustic louvre can be supplied with suchflanges which can be pre-drilled to allow fixing to the adjacentstructure. The louvre casing can alternatively be pre-drilledthrough the sides of the unit to allow louvres to be boltedtogether or when units are to be fixed into a timber frame.Fixing details of individual louvres are normally supplied atthe time of order but can be furnished on request.The height of the smallest EMTEC LAAC 15 Acoustic Louvre is300mm and larger sizes increase in height multiples of105mm (i.e: 405, 510, 615mm etc.). The height of thesmallest EMTEC LAAC 30 Acoustic Louvre is 650mm andlarger sizes increase in height by multiples of 225mm (i.e: 875, 1100, 1325mm etc.) up to a maximum height for a single louvre unit of 2450mm.All EMTEC LAAC 15 Acoustic Louvres have a standard depth of150mm. All EMTEC LAAC 30 Acoustic Louvres have a standarddepth of 300mm. Widths are made to suit customersrequirements up to a maximum width for a single louvre unitof 2400mm.Typical SpecificationInto Builderswork Opening:EMTEC LAAC 15 Acoustic Louvres shall be installed in thepositions indicated on the drawings to maintain the acousticcriteria shown in the specification. The acosutic louvres shallbe constructed from galvanized steel and be suppliedcomplete with external mounting flanges and birdscreensfixed to the rear face of the louvres. The louvres will bepolyester powder coated to a standard, non-metallic, BS4800or RAL colour.As Acoustic Screen:A screen of EMTEC LAAC 30 Acoustic Louvres shall beinstalled around the roof mounted chiller to a height of2450mm. The screen shall be mounted on a pre-formedconcrete plinth, 300mm high by 350mm wide, and suppliedcomplete with dummy corner units, structural supports and a louvred access door. The louvres are to form a self-supporting structure and the external finish will be blackplastic coated steel.UsageEMTEC LAAC 15 and LAAC 30 Acoustic Louvres are externalweather louvres with acoustically absorbent blade elementsspecifically designed to reduce the level of noise passingthrough the opening into which the louvre is mounted.The aerodynamic shape of the individual blades minimises theresistance to airflow and the incorporation of water trapsensures that rain ingress is effectively eliminated.EMTEC LAAC 15 and LAAC 30 Acoustic Louvres can beinstalled as individual units or by bolting more than one unittogether openings of any size can be accommodated. Eachlouvre has a robust outer framework which acts as vertical orhorizontal mullions when several units are fixed together. If acontinuous blade effect is preferred this can also be supplied.The main uses of EMTEC Acoustic Louvres are in the controlof mechanical fan noise when used as the termination ofducted air systems. Both exhaust air outlets and fresh airintakes can be fitted with EMTEC acoustic louvres. EMTECAcoustic Louvres can also be used as plantroom ventilationlouvres in order to attenuate general plant noise and asgeneral purpose ventilation louvres in order to reduceexternal aircraft or traffic noise. In all these applications thelouvres are normally built into structural openings and anumber of alternative fixing arrangements can be supplied. EMTEC Acoustic Louvres can be used as screens aroundequipment such as chillers, cooling towers or condensingunits where an acoustic barrier is required and large volumeairflows must be accommodated. In this application EMTECAcoustic Louvres may be supplied complete with corner units,supporting steelwork, doors and dummy sections in order toform a complete self-contained structure.It is advisable thatsuch applications be discussed with an EMTEC engineer whowill be pleased to assist you in the formulation of a detaileddesign layout.ACOUSTIC_LEAFLETS_ACOUSTIC_LEAFLETS.qxd 06/02/2012 16:57 Page 7Acoustic Louvres Type LAAC 30 & LAAC 15UsageTypical SpecificationConstructionSpecialist Engineers in Noise Control and Vibration Control, Architectural Louvre Systems and Plantroom WallsData sheets are issued in all good faith and the information given is current at the time of printing. However, EMTEC reserves the right to alter, amend or withdraw products as and when necessary.All rights to the products described in this data sheet are reserved to EMTEC.Emtec Products Ltd., Enterprise House, Blyth Road, Hayes, Middlesex, UB3 1DD. Tel: 020 8848 3031. Fax: 020 8573 3605. Email: sales@emtecproducts.co.ukIt may be necessary to establish the correct size ofacoustic louvre knowing that a certain pressureloss is required across the louvre for a givenvolume of air. In this case the face velocity of thelouvre is read off the chart opposite and thelouvre dimensions established from the formula:Airflow(Q) = Louvre Face Area (AL) x Louvre Face Velocity (VL)Conversely, for a known opening size and airflow,the pressure loss across the louvre can beobtained from the chart opposite.Selection Example:Assume the airflow is 5m3/sec and the structuralopening is to be made approximately 2000mmwide by 1500mm high. From the formula above alouvre face velocity is establshed as Q 5VL = –––– = –––––––– = 1.666m/sec.AL 2 x 1.5From the chart opposite this gives a pressure lossof 28 pascals. The exact louvre height nearest to1500mm high is 1525mm which would give a finallouvre selection as shown below.LAAC 30 Acoustic Louvre - 2000mm wide x 1525mm high x 300mm deep.AcousticPerformanceAerodynamicPerformancePhysicalPropertiesAcoustic Louvre Sound Reduction Index in dB at Octave band centre frequencies (Hz)63 125 250 500 1k 2k 4k 8kLAAC 30 & LAAC 15 5 7 9 12 18 19 15 15???????? ???? ????? ??? ????? ???? ?? ? ???? ?????????? ????????????? ???????? ???? ? ??????????BOLTFIXINGBOLTFIXINGWALLWALLWALLFLANGEFLANGETIMBERFRAMELAAC 30 OR LAAC 15ACOUSTICLOUVRELAAC 30 OR LAAC 15ACOUSTIC LOUVREEXTERNAL FLANGE FIXINGTYPICAL BUILDERSWORK DETAILSINTERNAL FLANGE FIXINGFIXING TO TIMBER FRAMELAAC 30 OR LAAC 15ACOUSTIC LOUVRESCREWBOLT FIXINGSLAAC 30 Acoustic Louvre.LAAC 15 Acoustic Louvre.ACOUSTIC_LEAFLETS_ACOUSTIC_LEAFLETS.qxd 06/02/2012 16:57 Page 8Acoustic PerformanceAerodynamic PerformancePhysical PropertiesEmtec Products Ltd, Enterprise House, Blyth Road, Hayes, Middlesex, UB3 1DD T: 020 8848 3031 F: 020 8573 3605 E: sales@emtecproducts.co.uk www.emtecproducts.co.uk Data sheets are issued in all good faith and the information given is current at the time of printing. However, EMTEC reserves the right to alter, amend or withdraw products as and when necessary. All rights to the products described in this data sheet are reserved to EMTEC.