Sheet Recommendations

TWINWALL & MULTIWALL SHEET SIZE RECOMMENDATIONS

For roofing installation, it is important to know that polycarbonate cannot hold its own weight, it needs supporting. Supports include the framework as well as rafters and purlins. Be aware that if the span of the polycarbonate sheet is too large, the sheets can sag / bow in between the rafters. Therefore, we have a list of maximum spans of sheets that we recommend you don’t exceed without the correct supports or accessories:

10mm Twinwall → max 700mm

16mm Multiwall→ max 800mm

25mm Multiwall → max 900mm

32mm / 35mm Multiwall → max 1000mm

Polycarbonate sheets may be cold bent, or curved up to their minimum permitted radius, using polycarbonate’s natural properties, without need of a thermal process. Curving sheets beyond this minimum permitted radius induces undue stresses and strains in the glazing sheet, causing premature failure and will void the warranty. Refer to the manufacturers technical guide.

EXAMPLE OF OUR CALCULATIONS

SHEETS:

5000mm ÷ 700mm = 7.14 (round up to 8 sheets)

5000mm ÷ 8 sheets = 625mm (centre to centre of the rafters)

8 Sheets @ 625mm x 3000mm

GLAZING BARS:

7 glazing bars x 15mm deductions = 105mm

5000mm – 105mm = 4895mm

4895mm ÷ 8 sheets = 612mm (width of the sheets required)

SHEET CLOSURES:

5000mm x 2 = 10,000mm

10,000mm ÷ 21000mm = 4.76 (round up to 5)

5 Sheet Closures @ 2100mm

RECOMMENDED ORDER REQUIREMENTS:

8 x Sheets of 10mm Twinwall Polycarbonate @ 612mm x 3000mm

Pre Taping Service: Yes

7 x Glazing Bars @ 3000mm

7 x End Caps for Glazing Bars

2 x Aluminium F-Sections @ 3000mm

5 x PVC Sheet Closures @ 2100mm

2 x Silicone Tubes

*Note we will only take into account the deductions for the glazing bars when requested. If you provide us with specific sheet sizes, we do not deduct anything for the glazing bars. *