Posi-joists ((hot)) | PLUS • Series |

For the contractor, Posi-Joists are a logistical dream. They are lightweight (one person can easily carry a 5-metre joist), arrive precut to length, and sit perfectly level on the wall plate. No more hunting through piles of warped, twisted, or crowned timber. And because the open web allows air to circulate freely, there’s less risk of condensation or dry rot in sealed floor zones.

Here is the moment every homeowner falls in love with Posi-Joists: the plumber arrives. Or the electrician. Or the HVAC technician. posi-joists

That is the , and it is quietly revolutionizing how we build from the ground up. For the contractor, Posi-Joists are a logistical dream

In a solid joist floor, running pipes or wires means drilling holes—often in the wrong place, weakening the structure, or forcing you to build bulky dropped ceilings to hide the mess. With Posi-Joists, the services simply run through the open web. No drilling. No notching. No compromise. The void between the flanges becomes a pre-planned superhighway for your home’s nervous system: wiring, water lines, heating ducts, and even speaker cables all weave through the steel lattice without touching the timber. And because the open web allows air to

They are not magic. Posi-Joists are typically deeper than solid timber for the same load (a 300mm Posi-Joist might replace a 220mm solid joist), so you lose a little more headroom. They are also marginally more expensive upfront. But when you factor in the hours saved not drilling holes, the money saved on service drops, and the lifetime of a stiffer, quieter floor, the math quickly flips.

At its core, a Posi-Joist is a hybrid. It consists of strong, solid timber flanges (top and bottom) connected by a sinusoidal or zig-zag steel web. This “I” shape gives it incredible strength-to-weight ratio. But unlike a traditional I-joist (made of OSB), the open steel web of a Posi-Joist is its superpower.

A Posi-Joist isn’t just a piece of the frame—it’s a piece of intelligence. It accepts that modern homes are not just places to walk, but complex ecosystems of heat, power, and water. By lifting the floor slightly and adding a web of steel, it turns the forgotten space beneath your feet into a thing of elegant, functional beauty.