FCO-3545  
 
 
 
 
 
 
 
   
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 Analysis of Minor Variations 
 
B.1 Variation to tested construction 
The proposed construction shall be a roof system as tested in FSZ 2411 when subject to the variations 
listed below; 
• 
The pitch of the roof may vary from 45 degrees tested to a roof with a pitch of 8 to 75 degrees.  
• 
The roof panel top steel skin shall vary from the tested Delta Trim roof profile to Delta Orb roof 
profile as shown in Figure 1 and 2. 
• 
The panel shall be a minimum of 100mm thick as per Figures 2 and 4. 
• 
Variation of fixings for panel to panel 
o The fixing shall be the tested 13g x 25mm self-drilling steel screws, or larger/longer in 
size. 
o The fixing shall be at least 200mm centres or closer.  
• 
Variation of fixings for panel to frame, barge edges, top the valley gutter steel skin to top of 
panel, ridge cap. 
o The fixing shall be the tested TEK 14g x 175mm Hex screws with cyclone clips, or 
larger/longer in size. 
o The fixing shall be at least 200mm centres or closer.  
• 
Variation of fixings for bottom of valley gutter steel skin to bottom of panel. 
o The fixing shall be the tested stainless-steel rivet, or larger/longer in size. 
o The fixing shall be at least 200mm centres or closer.  
• 
The mineral wool under the valley gutter may be as tested 50mm or thicker, with a minimum 
density of 38kg/m2 as per Figure 6. 
• 
Roof framing system may vary as follows;  
o The framing may be arranged and specified to meet AS 1684 timber framing code or 
NASH standard – steel framed construction in a bushfire area. 
o Framing details at eaves shall exclude gaps greater than 3mm.  
• 
The inclusion of the following sealants in all gaps including roof ribbing edges, joints on the 
upper and underside of the roof, valley gutter, barges, ridge, hips, and drip edges. 
o Boss FireSilicone-EMA sealant (as tested) or other fire-resistant silicone sealants such 
as  Sikasil 670 Fire Silicone Sealant. 
 
Roof pitch variation 
The proposed construction includes a roof that has a pitch that varies as follows: 
• 
The pitch of the roof may vary from 45 degrees tested to a roof with a pitch of 8 to 75 degrees. 
With reference to FSZ 2411, the roof pitch was tested at 45 degrees. Sustained flaming or gap 
formation was not observed during the test.  
With reference to AS 1530.8.1-2018 clause 17.2, it requires roof systems with a steep pitch to be 
evaluated separately from roof systems with a shallow pitch. 
With reference to AS 1530.8.1-2018 clause 17.6, it stipulates that if the roof with a pitch of 45 degrees 
has been tested, the result shall apply to roofs with a gradient of more than 18 degrees and less than 
75 degrees. The tested roof system in FSZ 2411 and the above discussion confirms that the proposed 
system meets this requirement. 
With reference to AS 1530.8.1-2018 clause 17.6, it also stipulates that the roof with a pitch of 18 
degrees that has been tested, the result shall apply to roofs with a gradient up to 18 degrees. The 

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