Industrial Grade Fibreglass Sheeting


Industrial Fibreglass has set the standard for Industrial skylights in Australia for many years. It provides cost effective lighting through excellent spanning, light transmission and low thermal expansion.

More recently, Zammit Roofing have developed Wonderglas GC, which provides all of the physical properties of standard Industrial Fibreglass, with ultimate durability through Zammit Roofing’s unique Gel Coat Technology. For more information on Wonderglas GC and Zammit Roofing’s Gel Coat Technology. Click here to view info.

Available Profiles

All current profiles (see link below) such as Corrugated, Trimdek (5-Rib), Speed-dek, etc. plus most superseded profiles are available. Click here to view profiles.


Zammit Roofing industrial & premium grade industrial fibreglass is manufactured to AS/NZS 4256.3: 1994, Licence No.986. Zammit Roofing are an AS/NZS ISO 9001 QEC.

N.B. Standard grade is surface protected with Melinex polyester film.

Hail Resistance

Zammit Roofing warrant series 2400 (and upwards) standard grade industrial fibreglass sheeting against damage from hail up to 20mm in diameter accompanied by winds up to 100 km/hr for 5 years. Premium grade gel coated sheeting is covered for 10 years.

Spanning Capacity

Industrial Standard and Premium Grades
Series 2400 3050 3660 4270 4880
Nominal Thickness 1.4mm 1.75mm 2.1mm 2.45mm 2.8mm
Corrugated 1200mm 1500mm 1700mm
5 Rib 1500mm 1700mm 2000mm 2300mm
Spandek 1600mm 2000mm 2300mm 2600mm 2800mm
Kliplok 406 1400mm 1700mm 2000mm 2300mm 2600mm
Kliplok 700 1400mm 1700mm 2000mm 2300mm 2600mm
Speed-dek 1400mm 1700mm 2000mm 2300mm 2600mm
LT7 1700mm 2100mm 2300mm 2600mm 2800mm

The above spans are recommended for wind loads up to 1.0 kPa.

For information regarding recommended spans in high wind and cyclonic regions please contact your local Zammit Roofing office.

Sheeting Grades

Series Weight (Kg/m2)
2400 2.4
3050 3.05
3660 3.66
4270 4.27
4880 4.88

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’).

Light and Heat Transmission

Series 2400
Light % Heat %
Ice Clear 70 68
Opal (white) 68 64

For Light and Heat transmission of other series (grades), please contact your local Zammit Roofing office. Other colours can be produced to order for viable quantities.

Expansion Data

Materials Expansion Comparison.  0° to 40° Temperature Variation.  Sheet Length 6 metres
Fibreglass Polycarbonate Steel Aluminium
Thermal Expansion 7.2mm 16.2mm 2.9mm 5.8mm
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

Physical Properties

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
Specific Gravity 1.45
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 “Corrugated” and “5-Rib”
Minimum Radius 4.0 Metres
Recommended Service Temperature Range -20° to +96°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

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:

  1. Fasten Fibreglass sheeting in the same manner as metal.
  2. When Job is completed, remove fasteners on fibreglass section.
  3. 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”.

Safety Data:

There are no ill effects from handling Zammit Roofing Fibreglass sheets as a finished product.

Some exposure to air-borne particles occurs on drilling, cutting and trimming of the material. Although there are no known cases of harmful effect, even after long term exposure, it is recommended to take certain precautionary steps.

Eye (contact) Can cause irritation. Appropriate eye protection should be worn. If irritation occurs due to exposure to dust particles, wash eyes with running water using an eye bath or wash bottle. If irritation persists seek medical attention.

Skin (contact) Can cause irritation. Shower thoroughly using soap and a cloth or sponge.

Inhalation (breathing) Dust masks are recommended although particles are not respirable.

Ingestion (swallowing) Non-toxic. Extensive studies have revealed no serious effects.

Emergency Fire Fighting Action

In the case of an indoor fire relating to stored Fibreglass Sheets the following action is necessary.

  1. Use a self contained breathing apparatus.
  2. Fire may be controlled by use of sand, carbon dioxide, dry powder or foam extinguishers.
  3. Water can be used to prevent fire from spreading to other goods or buildings.

Zammit Roofing Fibreglass :

Generally as a translucent, light transmitting, panel in roofs or walls of buildings. May find use in specialty applications due to resistance to corrosion. Can also comply with Building Code requirements when using Fire Retardant resins.

Physical Description: Zammit Roofing roof sheeting is the product of the halogenated polymerization of polyester resin by the addition of a suitable catalyst. The resin is supported by a matrix of chopped glass reinforcement. The sheeting is glass like in appearance and is odourless.

Ingredients: Polyester resin is an unsaturated thermosetting resin resulting from the esterification of suitable poly vasis acids and polyhydric alcohols dissolved in selected vinyl monomers. The catalyst system uses an addition of cumene hydro peroxide solution. The reinforcing is translucent sheet roving manufactured from E Type glass. The polymerization results in an inert resinous material.

Fire: Fire Retardant Sheeting has been tested in accordance with AS/NZS 1530.3-1999. It will support combustion and sheeting will only burn when flame assisted. All normal extinguishing media may be used. Thermal decomposition products include carbon monoxide, styrene, methyl methacrylate, acrid smoke and hydrogen chloride and bromide.

For further information contact your local Zammit Roofing Office. Warranty Industrial Fibreglass features a limited 10 year warranty. Premium Grade is warranted for 25 years. For full warranty details, please contact your nearest Zammit Roofing office.