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Bird Proof Purlins

Boxed Purlins ISO

Rollforming Services Boxed Bird Proof Purlins are designed as a replacement for Timber beams where larger spans are required. They are lightweight, dimensionally accurate and straight, they fit into shed structures utilizing the same joist hangers designed for use with Timber.
Boxed Purlins can be incorporated into C Purlin Portal Shed and Timber Pole Shed designs with ease. This allows them to be used in Herringbone Sheds, Wintering Sheds, Dry Feed Pads, Critical Storage Sheds, Implement sheds and canopies where Bird Proofing is a necessity.
There are 3 key reasons these Purlins are Bird proof
– The enclosed box section means there are no lips or channels for the bird to perch on.
– By mounting the Boxed Purlin between Portals rather than on top like other Purlin Products we greatly reduce the nesting points available to birds.
– The product is symmetrical, which reduces rolling of the section under load, therefore allowing us to remove the girts and bracing required by other products. The traditional strap bracing can just be fitted above the Purlins.

Another advantage of the boxed section is it’s increased span, when compared to similar sized profiles of both Steel and Timber. With our Boxed Sections we can span up to 9 metres in extra high wind and snow load.

They are also easy to install, simply mount the Joist Hangers to the Portal during assembly on the ground, then carry your pack of Boxed Purlins up with you on the Cherry Picker or Scissor Platform, they can then drop straight into the hangers at each end ready for you to connect using Tek Screws, no cumbersome bracing or nuts and bolts to deal with.

See our connection detail pdf’s attached to see how easily these attach to the building.

The Boxed Purlins are also lightweight,
• 150mm section 4.6kg per metre
• 190mm section 5.3kg per metre
• 240mm section 6.2kg per metre

Bird Proof Purlin Span Calculator
Our Span calculator will give you your Profile, Spacing, Span capability for a range of Building Categories, and Building Types to assist your building engineer in the design of your building. This is supported by the Section Properties and Engineering calculations document. Which are being reviewed by HERA.

Manufactured utilising the same AXXIS® Steel for framing that you see on TV, you know these purlins are covered by New Zealand Steels Durability Statement and that they will stand the test of time in New Zealand conditions. The 1.15mm High tensile steel provides ample pull out KN for all applications.

Rollforming Services Boxed Bird Proof Purlins used in a new build at Omata, New Plymouth.

Click here for the full article.

Technical Resources



Rollforming Services Ltd – Bird Proof Purlin Brochure


Rollforming Services Ltd – Bird Proof Purlin Drawings

imagesA Trial version of the Bird Proof Purlin Span Calculator is available now – send us your details to receive the download link for access.