EWPAA Structural Plywood and LVL Design Manual - Engineered ...

3 Structural Laminated Veneer Lumber (LVL)3.1 IntroductionStructural Laminated Veneer Lumber (LVL) is an engineered structural element with publishedengineering properties. All EWPAA / JAS-ANZ branded structural LVL is manufactured to comply withAustralian and New Zealand Standard AS/NZS 4357 Structural Laminated Veneer Lumber. This Standardsets out the minimum requirements for the manufacture, mechanical property characterisation andverification of the structural properties of LVL intended for structural applications, and for which,structural design is performed in accordance with AS 1720.1 Timber Structures Code, Part 1 - DesignMethods or NZS 3603 Timber Structures Standard - Code of Practice for Timber Design.LVL branded with the EWPAA / JAS-ANZ mark certifiesthe product has been manufactured to AS/NZS4357 andis suitable for use in all permanent structural applications.3.2 Bond TypeStructural LVL manufactured to AS/NZS 4357 has a Type A phenolic bond. The Type A bond isproduced from phenol or resorcinol formaldehyde and is recognisable by its dark colour. The Type A bondis durable and permanent under conditions of full weather exposure, long term stress, and combinations ofexposure and stress.Note:Even though the structural LVL phenolic bond is durable, the LVL will only be as durableas the timber species from which it is made. If the LVL is going to be used in weatherexposed applications or under other exposure conditions of severe hazard, the durabilityof the timber veneers must be considered and the LVL preservative treated to meet thehazard requirement.3.3 Timber Species UsedThe Structural LVL Standard AS/NZS 4357 permits the use of any hardwood or softwood timber veneersor a combination of both, in the manufacture of Structural LVL. The dominant timber species used inthe manufacture of structural LVL in Australia and New Zealand is plantation pine (radiata and Maritime).3.4 Stress Grade or Structural PropertiesStructural LVL is manufactured to a manufacturing specification that defines and limits all variables that affectstructural performance of that manufacturer’s LVL product. AS/NZS 4357 requires the manufacturer topublish the design properties for their LVL or adopt a stress grade classification as given for structuraltimber in AS 1720.1 or NZS 3603. Alternatively the manufacturer may determine the properties pertaining toa specific application, e.g. scaffold planks. Current practice for EWPAA / JAS-ANZ branded LVL, is formanufacturers to publish the design properties of their LVL as a suite of engineering properties and/ora set of span tables. The manufacturer’s brand name in conjunction with their published literature. Themanufacturer’s brand name or mark should therefore be included in any specification.12