DIN EN 14250:2010-05

This European Standard specifies material, product and documentation requirements for prefabricated structural members (for instance trusses for roofs, walls and floors, frames, composite beams and girders) for use in buildings made of solid structural timber according to EN 14081-1 with or without finger joints assembled with punched metal plate fasteners. This document is valid for trusses with lengths up to 35 m and for other prefabricated structural members with spans up to 12 m. The standard also covers tests and/or calculation methods to carry out the evaluation of conformity, requirements for the marking of these members, and the external conditions (service class 3 in accordance with EN 1995-1-1 or use classes 3, 4 and 5 in accordance with EN 335-1). As regards resistance to biological organisms, this standard covers prefabricated structural members manufactured from either untreated timber or timber treated to improve its natural durability. This standard does not cover prefabricated structural members intended to be used in constructions under predominantly dynamic loads (for instance bridges) or for use in unprotected external conditions (for instance use class 3 in accordance with EN 335-1). Furthermore, it does not cover members treated to improve fire performance. This document (EN 14250:2010) has been prepared by Technical Committee CEN/TC 124 "Timber structures", the secretariat of which is held by SFS (Finland). The responsible German Committee is Working Committee NA 005-04-01 AA "Holzbau" ("Timber structures") (Mirror Committee of CEN/TC 124, CEN/TC 250/SC 5) at DIN, the German Institute for Standardization. With respect to DIN EN 14250:2005-02 the following changes have been made: a) the scope has been limited to structural members under predominantly static load and has excluded bridge members; b) the normative references have been revised; c) new sub-clauses have been incorporated, 4.1.3 "Dimensional stability" and 4.1.4 "Reaction to fire"; d) requirements for timber preservative treatment have been specified in 4.1.5 "Resistance to biological organisms"; e) the contents of Clause 5 have been completely revised; f) the values of the specified dimensions (dimensional accuracy) indicated in 5.4.5 have been lowered; g) the product documents (Clause 6) contain new clauses on the contents of drawings and on the structural design documentation; h) the contents of Clause 7 have been completely revised; i) informative Annex ZA has been revised and explanations regarding Methods 1, 2, 3a and 3b have been included; j) examples of CE marking have been included for every method (1, 2, 3a and 3b).