Shadowline® WA Cyclonic

Fielders® have undertaken extensive and comprehensive testing on our roofing profiles for cyclonic regions. The following tables provide wind capacities and span values for the Shadowline™ WA roofing profile in cyclonic regions for both button punched and pan screw fixing types.

The cyclonic wind load capacities for Shadowline® WA roofing profiles is shown in Table “SLWA WC CY 001” and “SLWA WC CY 002” in this section.

Cyclonic Impact Resistance from Wind-Borne Debris

Parts of a building envelope (cladding, doors, windows) may be required to resist windborne debris according to AS/NZS 1170.2: 2011 and Technical Note No. 4, ‘Simulated windborne debris impact testing of building envelope components’, Cyclone Testing Station, James Cook University. These standards specify debris impact loading by timber member of 4kg mass with nominal cross-section of 100mm x 50mm and 8mm diameter spherical steel balls. SHADOWLINE® 305 (walling) cyclonic assemblies have been evaluated to effectively resist cyclonic wind-borne debris for wind region C and D when used in conjunction with 19mm plywood or KF40 backing, refer to the relevant fixing requirements for SHADOWLINE® 305.

For further information, please refer to sections “Rainfall Intensity” and “Water Carrying Capacity and Rainwater Run-Off”.

Figure SLWA RC NC 001

The allowable roof spans for the Shadowline™ WA roofing profiles in Regions C and D are shown in Tables “SLWA RS CY 001” to “SLWA RS CY 008”.

The allowable spans have been determined from tests carried out in accordance with AS 4040.0-1992, AS1170.2-2011 and the NCC (BCA) 2016 Specification B1.2 for the design of buildings in cyclonic areas.

The values in the maximum recommended span tables are based on strength. serviceability and foot traffic for the roof sheeting.

Figure SLWA CY 002 Local Pressure Factors

Note:
The local pressure factors (Kl) are shown in the figure above. Local pressure factors are not applicable at the ridge where the roof pitch is less than 10°. The value of ‘a’ is the minimum of 0.2 breadth, 0.2 width or the height.

Step 1

Fix a clip to the first and last purlin.

Step 2

Attached a string line to the first and last clip as a guide to fix the remainder of the clips to the purlins in between.

Step 3

Place the first sheet over the clips with the correct length into the gutter.

Figure SLWA IG CY 002

Step 4

Using the rib closing tool squeeze the male rib of the first sheet. Place top clip over each squashed male rib and fix to purlin. This needs to be done to prevent the sheet from lifting in the wind before the barges are fitted. The use of string lines will assist in ensuring sheets are installed straight.

Figure SLWA IG CY 003

Step 5

Make a small non-permanent mark in the pan to enable you to locate the clips in the latter locking operation with the button punch.

Step 6

Position the female rib of the next sheet over the male rib and clips ensuring that it is fully engaged. Fully engage the sheet with the clips using foot pressure on the ribs over each clip. You can do this by walking along the full length of the sheet with one foot in the tray next to the overlapping rib and the other foot applying pressure to the top of the interlocking ribs at regular intervals.

Figure SLWA IG CY 004

Step 7

Repeat steps 3 to 5.

Step 8

All lapped ribs must be locked along their length, by button punching at the clips, and if necessary between the clips (typically at 900mm centre to centre). Punching to a string line guide stretched across the sheeting is recommended as random punching marks the appearance of the finished work.

Figure SLWA IG CY 005

You must button punch through the hole in each top fixing clip, you can locate the clip with the non-permanent mark made previously. When operating the punching tool, stand on the pan of the overlapping sheet to ensure that the sheets are fully engaged.

Step 1

First set the depth that the button punch will punch.

Step 2

Place the button punch on its handles and lean it against a support with the button lining up with the face of the cup.

Step 3

Measure between the two punch holders (in photo about 24mm).

Step 4

Close the handles until the gap decreases by 2.0mm.

Step 5

Adjust the stop adjustment until it is set at that distance.

Step 6

Setting the distance down from the top of the rib of the roof sheet that the button punch is located.

Step 7

The distance from the centre of the button punch to the support guides is 17mm as shown.

Step 8

If this needs to be adjusted, loosen the set screws, adjust the stop and retightened.

Step 9

After you do the first button punch check that it is in fact punching to that dimension.

Step 10

Some minor adjustment may be required as it should punch in the centre of the hole in the clip.

Wind can drive water uphill under the flashings or cappings. Also, at the low end of a roof, wind or capillary action can cause water to run back up the underside of the sheeting. To minimise these problems, turn the pans up at the top of sheets, and turn them down at the bottom. A tool is available for these jobs (ref. Figure SLWA IG CY 006).

Figure SLWA IG CY 006

Flush turn-ups are usually used on Shadowline® WA. Cut off a portion of the female rib for at least 50mm. For a flush turn-up, you also need to cut the crown of the centre rib for at least 50mm.

Holding the end of the tool against the end of the sheet, pull the handle up 90°. If turning-up flush, fold the protruding ears flush against the turn-up tool with a rubber mallet (ref. Figure SLWA IG CY 006).

Figure SLWA IG NC 007

All roofing on slopes below 1 in 5 (10°) must be turned-down.

Turning-down is usually done after the sheeting is fixed on the roof, provided there is no obstruction to the operation of the turn-down tool.

Push the turn-down tool over the end of the tray, as far as it will go.

Hold the tool hard against the end of the tray and push the handle to form a turn-down of about 20° (ref. Figure SLWA IG CY 007).

Care needs to be taken when installing insulation with Shadowline® WA roof sheeting. When insulation thicknesses up to 50mm are installed the screws may need to be increased depending on the thickness and density of the insulation. When the screw is properly tightened into metal there should be a minimum of three (3) threads protruding past the support being fixed in to. For timber, the screw must have a minimum embedment of 25mm into timber.

When insulation is required in conjunction with Finesse® profiles, Fielders® recommend the use of a thermal spacer to help maintain Rw values as well as minimising any bulging in the profile caused by the insulation.

Insulation blankets and batts can cause wide flat pan cladding to bow out between the supports, between fasteners along the support, or bow the pans. For insulation blankets and batts as well as more dense glass wool and rock wool, and thicker insulation, spacers are recommended.