The typical spacing standards for residential and commercial buildings are about 1 to 2 foot.
Roof purlin spacing nz.
The minimum roof pitch for corrugate is 8 degrees approx 1 7 and if end lapped 10 degrees approx 1 6.
For heavier material such as gage steel the metal roof purlins spacing length could go up to 4 feet.
For the lighter material such as lightweight aluminum the common spacing length is 4 inches of clear gap.
Purlins up to 1200mm spacing must be fixed with a 1 10g 80mm long purlin screw minimum or a pryda purlin strap bs 70.
Doubling up in the valleys refer to the installation manual for the proper on center spacing and be sure that the purlin is attached to the roofing truss.
Longer lengths require specific design.
Or ultimate loads in respect of clip fastened products ultimate loads can be converted to serviceability loads if necessary by applying a factor of 71 in all parts of the country.
Purlins typically 75 x 50 mm and fixed across the rafters were spaced at 760 900 mm centres depending on the roof cladding.
When a combination of sheets provide a run of in excess of 40 metres and up to 60 metres the roof pitch should be increased by 1 degree.
Where the end purlin spacing is less than 800mm an adjustable end brace with a bolted end cleat is available as twisting of the end cleat is not practical.
Step 1 rafter spacing the rafter span is 3 000 m and because this is a light roof the far right column of nzs 3604 2011 table 10 1 rafters for all wind zones see figure 2 can be used for rafter spacings at 1200 mm see note 4 in table 10 1.
Roof bracing hipped roof construction does not require additional bracing but gabled roofs require both roof plane and roof space bracing.
The adjustable cleat can be rotated up to 15 degrees from normal to accommodate the change in angle from vertical portal to the roof slope of the rafter.
Step 3 purlin spacing suntuf is supported on the structure via purlins these are the bearers that run left to right along the width of the roof the maximum purlin spacing for the corrugated profile is 800mm centres on the first and last purlins and 1 meter centres for the intermediate purlins.
It should be noted that timber purlins for metal roof cladding are minimum 70mm x 45mm h1 2 18 moisture content and that battens used previously for tiles must not be used.
