All structural timber must undergo an assessment of their strength reducing defects usually carried out by grading machines or trained visual strength graders. These activities are regulated by European and
national standards; the main standard being I.S. EN 14081-1:2016 “Timber structures - Strength graded
structural timber with rectangular cross section - Part 1: General requirements”; this specifies not only CE
marking (applicable to all harmonised standards) but also ‘general’ marking which is separate to the CE
marking. Visually graded timber is usually undertaken by national standards which should comply with EN
14081-1. The Construction Products Regulations requires that there must be a Declaration of Performance
before a product can be CE marking.
Visually graded timber is usually undertaken by national standards which should comply with EN
14081-1. The national visually grading standard for Ireland is I.S. 127 “Structural timber – visual
strength grading – Sawn softwoods with rectangular cross-sectional”.
EN 14081-4 “Machine grading – grading machine settings for machine controlled systems” has been
withdrawn and machine settings are now given in Approved Grading Reports.
Each individual piece of visually graded timber using I.S. 127 must be marked. Timber graded using
visually grading standards of other member states is acceptable provided the standard complies with
EN 14081-41 and the timber has been put on the market legally and has a Declaration of
Performance and is CE marked.
EN 14081-4 “Machine grading – grading machine settings for machine controlled systems” has been
withdrawn and machine settings are now given in Approved Grading Reports. Each individual piece
of machine graded timber must be marked.
The Construction Products Regulations requires that there must be a Declaration of Performance
before a product can be CE marked.
I.S. EN 1995-1- 1:2004+A2:2014 “Eurocode 5: Design of timber structures – Part 1-1: General -
Common rules and rules for buildings” along with the national annex is the main design standard
for use in Ireland. Designs should use the appropriate loading standards and their national annexes.
SR 71:2015 “Timber in Construction – Span Tables and Guidelines” provides non-
contradictory complimentary information (NCCI) on designs using Eurocode 5. There are load span
tables for floor joists, ceiling joists, flat roofs, roof rafters and purlins. Advice is given on purlin
supports and timber studding (but not timber frame). There is also a method to allow wind loads
acting on a roof to be estimated.
See Information Sheets
WTI-03 Structural Timber - Marking For Solid Timber
WTI-05 Structural Timber - General Design Requirements
See New Publications
The Structural Use of Timber - Handbook for Eurocode 5: Part 1-1 by Malcolm Jacob, James Harrington and Bill Robinson