I-Joists | Structural Timber & Framing | Birak Building Products

Category Structural Timber & Framing

Type Engineered Wood

Variants 8 available

Availability In Stock

Delivery Australia-wide

Variants

8 of 8

400x58 Spec Joist 70 Series H2-S Request
300x47 Swelite I-Joist H Series UT Request
240x70 Swelite I-Joist HI Series UT Request
300x70 Swelite I-Joist HI Series UT Request
360x70 Swelite I-Joist HI Series UT Request
300x97 Swelite I-Joist HB Series UT Request
360x97 Swelite I-Joist HB Series UT Request
400x97 Swelite I-Joist HB Series UT Request

Frequently asked questions

What spans can I-joists achieve compared to solid timber joists?

I-joists deliver substantially longer clear spans than equivalent solid MGP joists because the deep flanged web concentrates structural depth efficiently. A 300mm-deep I-joist typically spans further than a 240x45 MGP10 with less floor deflection and reduced bounce. Birak stocks I-joists from 240mm up to 400mm deep, including the Spec Joist 70 Series H2-S at 400x58 and the Swelite range from 240x70 through 400x97, letting designers tune span and centres to suit each room.

What's the difference between Spec Joist H2-S and Swelite UT I-joists?

Spec Joist 70 Series is supplied in H2-S termite-protected grade, suitable for use in BCA termite-risk zones. Generally most of mainland Australia. The Swelite I-Joist H, HI and HB Series are supplied untreated (UT) and suit applications outside termite-risk areas, or where a separate termite management system is in place. Both ranges deliver the same dimensional stability and long-span performance. Selection comes down to project location and termite management strategy.

Why are the Swelite I-joists offered in three series. H, HI and HB?

The H, HI and HB designations reflect different flange widths. The 47mm H Series suits standard residential floor and roof joist applications. The 70mm HI Series provides increased bearing area and stiffness for higher loads or longer spans. The 97mm HB Series, supplied at 300, 360 and 400mm depths. Is the heavy-duty option for commercial floor structures, large residential builds and heavier loading conditions where extra flange capacity is required.

How do Birak I-joists ship across Australia?

I-joists ship from Birak's distribution network direct to site nationwide. Lead times for typical residential orders are 5 to 10 business days, with scheduled deliveries available for staged commercial projects. Most state-bound competitors require interstate buyers to coordinate freight separately. Birak quotes delivered to your site in any state or territory on a single PO, with care taken to handle the long flanged sections without damage.

Do I-joists count toward Indigenous Procurement Policy spend?

Yes. Birak is Supply Nation Registered, so every dollar spent on Spec Joist and Swelite I-joists, and any other product we supply, counts toward your IPP Indigenous procurement target. Audit-ready procurement documentation is supplied automatically with each invoice, which simplifies reporting for Tier 1 builders, Commonwealth-funded projects and head contractors with Reconciliation Action Plan commitments.