The quick answer is YES. Roof battens no matter how you look at them are a structural element of any roof.
Definition of a Structural Defect
1.4.14 Structural defect:
Fault or deviation from the intended structural performance of a building element. A roof batten is both a building element and a structural element.
Definition of a Major defect
1.4.10 Major defect
A defect of sufficient magnitude where rectification has to be carried out in order to avoid unsafe conditions, loss of utility, or further deterioration of the property.
Roof Tile Battens
Roof Tile battens are a structural element of the roof frame as per the Australian standard’s definitions:
Roof tile batten – member fixed to trusses or rafters to support sheeting or tiles
Member – a single structural element, including truss chords and webs
Supporting Member – the member to which the cladding is attached (e.g. purlins, battens, girts)
any timber component or element forming part of the loadbearing framework of a structure including but not limited to structures as classified in the Building Code of Australia
The decision of which roof batten material is right for your home is vital. Similarly is the design of any system.
This is because your roof battens help spread the load stresses. Such as wind (uplift and direct loading) and weight across the stick roof or roof truss system.
Roofs can be subjected to great forces most notably during high wind and cyclonic events. Equally important to note many roofing systems have failed due to the use of incorrect fasteners. in the same fashion, they could choose the wrong roof batten material choices.
It is essential to get the correct advice whether you are designing and constructing a new roof. Likewise undertaking a complete roof replacement.
Roof battens are one of those constantly misdiagnosed and overlooked aspects of construction. But they provide some extremely important structural functions to protect your home.
Roof battens: Provide a breathable space that allows condensation to be minimized. Allowing roofing materials to be fastened securely to the roof trusses Increase the roof truss and stick roof systems’ structural performance help with alignment of colorbond or zincalume roofing sheets
Timber Roof Battens
TILED ROOFING | METAL ROOFING
Hardwood or Timber roof battens are known as the traditional roof batten material. They have successfully stood the test of time.
Timber roof battens can be used for all types of roofing including tile and metal or colorbond. However, it is essential that they are correctly engineered and take wind loading for your specific suburb or town.
Hardwood is the preferred choice in areas with higher winds. This is because mechanical fasteners can be torn out of softer woods such as pine.
There is a considerable difference too in the amount of pull resistance that can be offered by seasoned wood. When it is compared with green wood.
Most forget that suction or uplift causes considerable destruction by the wind to roofs. So it is absolutely vital that your engineer makes the correct calculations. Engineers are guided by the span tables in AS1684.
Timber battens are generally used when undertaking tile roofs. Whether you are using terracotta roof tiles or concrete roof tiles.
If you are completing a replacement with tiles you may find that some of the original battens need to be replaced. Equally important For tiled roofs using Timber they must meet the requirements of AS 1684.2, AS 1684.3 or AS 1720.1.
Timber battens for metal cladding come in a range of sizes:
75 x 45
90 x 35
90 x 45
Your options of size here will be determined by the weight and span of your metal roof panels.
Each product requirement is different. For example, spacing for (0.42BMT) metal roofing needs to be no more than 1100 mm apart. Whereas spacing for 0.48BMT metal roofing can spread up to 1600 mm apart.
Click here for confirmation from our friends at wood solutions. They will help with the guidelines of the Australian Standards 1684.2 timber framing guide.