Background
There has always been a British Standard for roofing battens. However in the past often scant regard has been taken of it. Over the years the requirements have been made clearer and given greater emphasis.
Pre 1997: This was the era of under measure battens. The tolerances were misinterpreted and there was widespread use of 22mm thick or 25mm nominal battens.
- The first stage on the path enforcing graded battens was BS 5534:1997, pt1. This brought in type A and B species, differentiating between the stronger imported species (17% stronger in bending and stiffness than Homegrown Spitka Spruce) and the weaker homegrown ones (mainly Spitka Spruce). There was also the first move to 25x50 for single lap tiling. However, a calculation method allowed the continued use of Type A 25x38. Heralding the use of marked battens. This era also saw 19x38 derecognised as a standard size.
- The next stage was British Standard BS 5534:2003 The Code of Practice for Slating and Tiling. It replaced the edition first published in 1978, later updated in 1990 and 1997. The new British Standard had significant commercial implications for everyone in the construction industry involved with specifying, supplying or fixing slating and tiling battens.
- The present: BS 5534:2003 is now in its 5 year review stage and included in its continuous improvement will be a tighter specification for roofing battens.
-
New BS 5534:2003+A1:2010. The standard has just been updated and there are two key changes with respect for roofing battens. One of these is the reduction in the size of through knot ( a knot that passes from edge to edge) and that battens must be free from distortion (there are tolerances for bow, twist and spring).
Since marking was introduced in 2003 more and more battens are marked or ‘stamped’.
Some of these may not have been fully graded. It is important to check with your
supplier about the degree of grading that has taken place. Whilst some suppliers
use an alternative grade code, many do not and continue to mark BS 5534, despite
the fact that, when asked, they confirm that the batten needs grading on site.
John Brash only marks its distinctive JB-RED with BS 5534 – its credentials are
of course further identified with the red colouration; all other battens are
marked TB33 denoting the requisite final grade on site.
