Low expansion and contraction rates make “Fire Retardant SL” premium grade gel coated fibreglass compatible with all steel roofing and cladding. When installed to Australian Standard AS2424, 1991 continuous lengths up to 12.2 meters may be specified.
All current profiles (see link below) such as Corrugated, Trimdek, Speed-dek, etc. plus most superseded profiles are available.
Zammit Roofing premium Industrial grade “Fire Retardant SL” fibreglass is manufactured in strict accordance with AS/NZS 4256 parts 1 & 3: 1994. Standards Licence No.986.
N.B.”Fire Retardant SL” is coated with Melinex polyester film. Premium grade with gel coated surface is also available. The highest quality materials available and the very latest resin technology are used in the manufacturing process.
|Industrial Standard and Premium Grades|
The above spans are recommended for wind loads up to 1 kPa.
For information regarding recommended spans in high wind and cyclonic regions please contact your local Zammit Roofing office.
Important: Heavier grades give the specifier the option to use Zammit Roofing sheeting in cyclonic zones, or match the span of the nominated steel roofing material (see ‘Spanning Capacity’).
For Light and Heat transmission of Series 4270, 4880, please contact your local Zammit Roofing office. Other colours can be produced to order for viable quantities.
|Materials Expansion Comparison. 0° to 40° Temperature Variation. Sheet Length 6 metres|
|Thermal Co-efficient||3.0 x 10-5 cm/cm°C||6.75 x 10-5 cm/cm°C||1.2 x 10-5 cm/cm°C||2.4 x 10-5 cm/cm°C|
|Tensile Strength||80 Mpa|
|Impact Strength||8 Joules|
|Shear Strength||90 Mpa|
|Modulus of Elasticity||5500 Mpa|
|Compressive Strength||135 Mpa|
|Flexural Strength||150 Mpa|
|Thermal Expansion||3.0 x 10-5 cm/°C|
|Thermal Conductivity||0.158 watt/m°C|
|Water Absorption||.2% in 24hrs./26°C|
|Curved Roof Radius||2400g/m2 “Custom Orb” and “Trimdek”|
|Minimum Radius||4.0 Metres|
|Recommended Service Temperature Range||-20° to +95°C|
The following installation procedures are recommended by the product manufacturers — Zammit Roofing Australia Pty Ltd.
These recommendations closely follow the Australian Standard: Design and installation of Sheet Roof and Wall Cladding, Part 3: Plastic. AS 1562.3-2006
Where wire safety mesh is incorporated under the fibreglass sheeting and over a purlin, a protective purlin strip must be installed to prevent fracturing. Zammit Roofing manufacture a 65 mm wide self adhesive fibreglass strip which, when viewed from below is not visible.
In roofing applications, fixings shall be fitted through the crest of any profile. Oversize screw holes from 10 mm up to 15 mm must be drilled at all points of fixing. Only 32 mm ‘Weatherlok’ seals should be used. These seals are large enough to cover the oversize hole and are sufficiently flexible to contour to any corrugation (or rib) when medium pressure is applied. Medium pressure means that the ‘Weatherlok’ seal is contoured to the shape of the corrugation (or rib), but rib or corrugation must retain its shape without any sign of buckling.
Contractors must make sure that the fixing is located in the centre of the oversize hole, or the benefit of the larger hole is lost. To ensure accuracy, Zammit Roofing recommends the following:
- Fasten fibreglass sheeting in the same manner as metal.
- When Job is completed, remove fasteners on fibreglass section.
- Using the existing screw hole as a guide, drill an oversize hole, swap neoprene washer (used in step 1) with ‘Weatherlok’ seal and reinstall the fastener.
Zammit Roofing design and recommend the fibreglass sheets to be installed on top of metal roofing on both sides. The sheet rib can still go over and under when fibreglass sheets are installed side by side.
Where fibreglass sheets are end lapped including those with dissimilar materials, two lines of Lapseal Tape or a flexible sealant shall be placed across the full width of sheet. Each strip is placed approximately 150 mm apart with one line located 25 mm from the end of the fibreglass sheet. Zammit Roofing recommends the use of 25 mm Lapseal Tape as silicone sealants can harden and cure due to exposure to daylight. The over-lapping sheets then become locked together as one sheet, effectively stopping movement between the sheets, and possibly causing buckling. With decking profiles install Lapseal Tape in the tray only or use a flexible sealant.
Fibreglass sheeting is not easily reshaped after manufacture, and will require special weather seals to be provided at all flashing and capping points. Typically, a foam closure strip matching the profile of the fibreglass sheet should be bonded to the pans or valleys with a flexible weatherproof sealant. Ideally it should be fitted at least 100 mm behind the turn down of the flashing.
Zammit Roofing fibreglass sheeting (with the exception of Webglas GC) is a non-trafficable material. Sheets should be handled with care to avoid damage to the surface coating which is either Melinex film or Gel Coat according to the grade. Guarantees will not apply to sheeting that has been damaged in handling, or mechanical damage due to foot traffic.
Furthermore, unless the above instructions are strictly adhered to, Zammit Roofing Australia Pty Ltd cannot accept any responsibility for consequent leakage problems, caused by sheets buckling or “ocean waving”.