Roofing batten failure is not common but, when it does happen, the repercussions can be costly, dangerous and even fatal.

The consequences of selling a batten incorrectly marked or graded, a product not fit for purpose, would also come under the Sales of Goods Act (1979).

The main reasons for failure are the use of battens which contain serious flaws, or are below recommended sizes. In these cases it is often impossible to secure adequate mechanical fixings into the battens, or they may not be capable of supporting the loads on the roof.

When the revisions to BS 5534 became effective in late 2003, they put much more emphasis on quality, accountability and safety when working at height. The most significant change was the upgrade of all batten sizes from 25×38 to 25×50 for single lap tiling on 600mm rafter centres. This was to ensure that the batten was more robust and less inclined to bounce. Also, the new standard reinforced the significance of grading battens according to wane, fissures, splits, rate of decay, insect attack and resin pockets. As a result, stricter site checks by inspectors can result in non-compliant battens being condemned, possibly resulting in the removal and refixing of roof tiles. The ideal solution would be to pre-grade battens at the sawmill – rather than inexact and costly grading on-site. but until now, this has not been technically possible.

However, thanks to some pioneering work and a great deal of investment in equipment such as optical and laser scanning, planing and improved mechanical handling, John Brash & Co Ltd has developed a pre-grading process at its sawmill. The resulting product is known as John Brash RED.

With small section timber such as roofing battens, tolerances are measured in millimetres, and this makes it virtually impossible to reliably assess any defects manually, or at an acceptable commercial speed. John Brash’s high precision automated scanning procedure, which is new to the UK, ensures that each individual batten is scanned as its passes down the line. At a speed of 250m per minute, the system analyses each piece of timber and, using complex software, any defects are measured and assessed for acceptability against prescribed profiling criteria. Checks are also made to measure the slope of grain and the rate of growth, both of which are vital in assessing timber strength. A unique preservative process is applied as well which both significantly reduces the overall weight of each batten and ensures that the batten has the correct moisture content at the time of fixing.

On-site productivity

As the battens are fully pre-graded, on-site productivity is improved as there is no need to spend time inspecting and manually grading the material. The use of a fully graded batten prior to delivery on site therefore eliminates the need to train and detail roofers to complete on-site grading. Roofers are assured that each batten is individually assessed and graded, and installation is easier because battens are lighter in weight than any alternatives. Contractors can be confident that all products will pass a building control or quality inspection visit.

In developing the RED batten range, Brash has worked closely with the BRE and will carry BRE Certification to meet the requirements of BS 5534:2003 and BS 8417:2003. This certifies that both the operational process controls and calibration systems in place are of a standard to ensure manufacturing consistency

Under BS 5534 Part 1:2003, type ‘A’ (imported) and type ‘B’ (home-grown) timber are no longer acceptable descriptions. However, species must still be identified as imported or home-grown, or the individual species code used. Imported timber is still recognised as being the significantly stronger option and the new pre-graded battens use superior imported whitewood (WPCA) and redwood (PNSY). Both species are slow growing, with close, tight annual growth rings, which result in stronger bending and stiffness qualities. All products are environmentally certified.