DIN EN 16481:2014-09

This document (prEN 16481:2012) has been prepared by Technical Committee CEN/TC 175 "Round and sawn timber", the secretariat of which is held by AFNOR. This document is currently submitted to the CEN enquiry. This document is addressed for structural designers to design timber stairs according to a common European method; it should be useful for SMEs as an alternative to testing where applicable. This standard takes into account the current state of the art regarding safety concept, loading assumptions, determination of stress resultants, as well as dimensioning in the field of wood engineering. The requirements and verification procedures essential for the verification of mechanical performance characteristics, serviceability and load-bearing capacity of stairs and their components are compiled and described in the following clauses. The mechanical performance characteristics of stairs may be verified by using the following methods: - testing of stairs as a whole or in part; or - mathematical verification on the basis of appropriate system approvals; or - assessment based on experience: conventionally accepted performance (CAP). All methods are equally valid. This European Standard constitutes a frame standard for the design of timber stairs as well as wood and wood-based components used in stairs by calculation methods. Some calculation methods can be derived from testing results, for example CEN/TS 15680. This document specifies the design and the requirements for materials and components to be used in these calculation methods. It may be complemented by national application documents based on this standard. This European Standard applies to coated and uncoated components. This document covers load-bearing components such as strings, treads, risers, posts and guardrails. This document contains calculation examples in Part 2 (or Annex, see separate document N 283). The requirements for a timber stair are defined in the product standard EN 15644. This document does not cover stairs that contribute to the overall stability of the works or the strength of the structure. This European Standard is valid for the verification of mechanical performance characteristics, usability and load-bearing capacity and their related durability. Other requirements, for example requirements for acoustic properties, are not covered by this standard. For the design, calculation and determination of not solely resting actions, additional requirements need to be taken into account. For the dimensioning with special reference to resistance to fire and earthquake/seismic action, additional requirements may be taken into account. The body responsible for this standard is NA 042-01-14 AA "Rund- und Schnittholz - SpA zu CEN/TC 175 & ISO/TC 218" ("Round and sawn timber - mirror committee CEN/TC 175 & ISO/TC 218") at DIN.