AS 2050:2018 pdf download.Installation of roof tiles.
SECTION 3 INSTALLATION
3.1 SARKING
3.1.1 General
Sarking shall be provided for all roofs where the design wind classification category is greater than N3. Where required, pliable and reflective-foil sarking shall be installed in accordance with AS/NZS 4200.2. Where rigid or semi-rigid material is used as sarking, it shall be installed to provide means for the water to discharge to the eaves gutter. NOTE: Sarking may also be necessary in other circumstances depending on roof pitch, length of rafter, fire hazard or tile type.
3.1.2 Anti-ponding device/board
An anti-ponding device/board shall be provided as follows: (a) On sarked roofs with pitches of less than 200.
(b) On all roof pitches where there is no eaves overhang.
3.1.3 Damage
Any tears or punctures. other than those caused by the installation of fixings over rafters, shall be repaired with a purpose-made sarking tape. NOTE: Care should be taken to avoid damaging the sarking during installation or tile-installing operati otis.
3.1.4 Requirements for roofs without general sarking
Water shall not be discharged from a gutter/valley or downpipe onto tiled roofs, unless provision is made to prevent inundation of the tiling or to conduct penetrated water away. Such provisions would include spreader pipes, flashing or sarking. The provision of spreader pipes or flashing shall be in accordance with ASINZS 3500.3. Where sarking is used, it shall be a minimum width of I 0O mm, either side from the point of discharge, and extended into the eaves gutter.
3.1.5 Long rafter lengths
Maximum rafter lengths, measured from the topmost point of the rafter downwards, shall be in accordance with Table 3.1.5, below which sarking shall be installed over the remainder of the rafter length.
3.2 BATTENS
3.2.1 General
Timber battens and rafters shall be installed in accordance with AS 1684 and AS 1720 series, as appropriate, and Clause 3.2 of this Standard. Metal battens and rafters shall be installed in accordance with the NASH Standard, Residential and Low-rise Steel Framing, Part I: Design Criteria, and Clause 3.2 of this Standard. Metal battens affixed to timber trusses shall be installed in accordance with Clauses 2.2.2 and 3.2 of this Standard.
3.2.2 First course of the roof tiles
At the gutter, the profile of the roof shall be maintained by the use of tilting battens and/or fascia boards.
3.2.3 Batten alignment
Battens shall be aligned when secured to within a tolerance of ±10 mm in 4 m, measured along the top edge of the batten.
3.2.4 Batten spacing
Battens shall be installed to the specified spacing/gauge. The tolerance shall be not greater than ±5 mm. Unless otherwise specified, the tile end-lap shall be not less than 75 mm.
3.2.5 Batten installation
Battens laid on the flat shall be fixed to every support with at least one nail or other mechanical installation. Battens laid on edge shall be secured by double fastening or be blocked. Battens in excess of 75 mm in height shall be blocked or otherwise restrained from overturning. Battens wider than 50 mm shall be secured with two fastenings to each rafter or truss. NOTE: For acceptable nail sizes, see Appendix C. Where a batten crosses a multi-ply truss, it shall be fixed to each chord of the truss with at least one nail or other mechanical installation as shown in Figure 3.2.5.
3.2.6 Fixing steel battens to steel trusses or rafters
Fixing steel battens to steel trusses or rafters shall be in accordance with Table 3.2.6.
3.2.7 Batten joints
All batten joints shall be, at minimum, butt joined and staggered so that each grouping of three battens does not contain any more than one joint on the one rafter, with the exception of steel battens which shall be lapped over the same rafter or joined between rafters using a mechanical joiner designed to conform to AS/NZS 1170.1 and NASH Standard, Residential and Low-rise Steel Framing, Part 1: Design Criteria. Battens shall not be joined on a multi-ply truss or a girder truss. Timber battens shall not be joined in the area formed by a gable end and the steel brace. NOTE: For an example of batten joints, see Figure 3.2.7.AS 2050 pdf download.