ČSN EN 16351 ed. 2

(73 2832) This document sets out provisions regarding the performance of characteristics of the following Types of cross laminated timber for use in buildings and bridges: - Type 1: Straight or curved cross laminated timber comprising only timber layers but no large finger joints; - Type 2: Straight cross laminated timber comprising only timber layers and large finger joints; - Type 3: Straight cross laminated timber comprising timber and wood-based panel layers but no large finger joints. This document covers cross laminated timber of all three Types of cross laminated timber: - manufactured according to this document, which sets up provisions for: - boundary conditions during manufacture of cross laminated timber; - moisture content and temperature of timber to be bonded; - production of finger joints and bonds between layers; - to be used in service class 1 or 2 according to EN 1995 1 1; - made of coniferous species and poplar listed in this document; - which may be made of layers made of different species; - bonded with phenolic or aminoplastic or moisture curing one-component polyurethane or emulsion polymer isocyanate adhesives of adhesive Type I according to the respective standard; - made of timber laminations having a nominal width between 40 mm (including) and 300 mm (including); - built up of at least three orthogonally bonded layers (at least two of them timber layers); - which may have, depending on the number of layers, adjacent layers bonded parallel to the grain; - made of timber layers which are made of strength graded timber according to EN 14081 1; - made of timber layers having nominal thicknesses between 6 mm (including) and 47 mm (including); - made of timber layers which may comprise edge bonds; - having nominal overall thicknesses up to 500 mm. Additional provisions of this document apply for straight cross laminated timber comprising only timber layers and comprising large finger joints (Type 2): - made from cross laminated timber pieces having the same cross-section and layup; - made from cross laminated timber pieces having nominal cross-sectional thicknesses from 51 mm (including) up to 345 mm (including) and nominal minimum thicknesses of the outer layers not less than 17 mm (including); - made from cross laminated timber pieces solely comprising timber layers; - made from plane cross laminated timber pieces; - with parallel x-axes of the jointed components; - with large finger joints having a finger length of at least 45 mm and fingers which are visible at the two narrow sides of the components; - having large finger joints bonded with phenolic or aminoplastic or moisture curing one-component polyurethane adhesives of adhesive Type I according to the respective standard. Additional provisions of this document apply for straight cross laminated timber comprising timber and wood-based panel layers but no large finger joints (Type 3): - made of structural wood-based panels specified in this document; - made of one panel per layer and; - having thicknesses between 6 mm (including) and 45 mm (including). This document applies to cross laminated timber untreated or treated against biological attack. This document does not cover: - cross laminated timber treated with fire retardants; - cross laminated timber which is produced from re-used timber or wood-based panels comprising re-used timber. It also lays down procedures for assessment and verification of constancy of performance (AVPC) of cross laminated timber.