WIDESPAN 762 ROOF SHEETING
Widespan is a roofing and cladding profile designed as an economic alternative to IBR. Widespan offers greater spans and lower roof slopes than Corrugated sheeting with the same covering width. Widespan can be cranked, curved and bullnosed to customer specifications.
Widespan is manufactured with a stiffening rib in the broad flute in order to minimise waves in the broad flute of the profile. If sheets without the stiffening rib is specified no claims for waving (oil canning) will be entertained.
Load span characteristics are to be used as a guideline only as purlin spacing also depends on other factors e.g. the wind conditions in a certain area, the type of structure or load bearing elements such as solar geysers. An engineer should determine the purlin spacing of a structure after considering the complete design. Approximate spanning capabilities of Widespan is as follows:
Widespan (0.762 mm) Approximate Purlin Spacing – (m)
Thickness & Coating
|Steel Grade||Full Hard||IQ550||ISQ550||ISQ300||ISQ300|
|Minimum Bullnose Radius||450 mm||450 mm||450 mm||300 mm||300 mm|
|Thickness tolerance||+-0.02 mm||+-0.02 mm||+-0.02 mm||+-0.02 mm||+-0.02 mm|
|Weight per metre||3.72 kg / m||3.72 kg / m||3.72 kg / m||4.18 kg / m||4.18 kg / m|
|Weight per sq metre||4.882 kg / m2||4.882 kg / m2||4.882 kg / m2||5.486 kg / m2||5.486 kg / m2|
|Roof – single span||1.25||1.25||1.25||1.40||1.40|
|Roof – double span||1.50||1.50||1.50||1.60||1.60|
|Cantilever – roof||0.40||0.40||0.40||0.50||0.50|
|Wall – single span||1.80||1.80||1.80||1.90||1.90|
|Wall – double span||2.20||2.20||2.20||2.40||2.40|
|Cantilever – wall||0.75||0.75||0.75||0.9||0.9|
|Approximate life span (years)|
|Industrial area||5 – 10||10 – 20||10 – 20||10 – 20||10 – 20|
Widespan is available in lengths of up to 14 metres with a length tolerance of -0 +5 mm. Sheets lengths up to 15.8m are available on enquiry.
When bullnoses and curves are designed a maximum permissible transport height of 4.3 metres is applicable.
When using Widespan, the recommended minimum pitch for roof slopes in excess of 15.8m is 10º and for slopes less than 15.8m is 7.5º.
The minimum end laps for roofs pitches >15º is at least 150 mm and 250 mm for other roofs. Side cladding end laps should be at least 100 mm.
It is recommended that end laps on roofs <10 degrees are sealed with a bitumen sealing strip to ensure water tightness.
The required number of Widespan sheets can be calculated as follows:
Length of building plus gable overhangs – (minus) 50 mm
Number of sheets = 0.762 m (Cover width of sheet)
The result of the calculation is then rounded up to the next sheet
Widespan must be fixed with one corrugation side lap with the narrow flute uppermost and fastened through the crests of alternate flutes to purlins using 65 mm Tek screws into steel purlins and 90 mm Tek screws for timber roofs, each fasteners must incorporate a 19 mm bonded washer.
For side cladding broad flutes can be fixed externally with fasteners in the web of the flutes. Side cladding can be fixed using 25 mm Tek screws with a 19 mm bonded washer.
For a quick calculation 3 fasteners per sheet per purlin can be used.