Floor trusses, posi joists and I-joist floor systems
We make floor trusses, often called posi joists, with timber or steel webs, and supply I-joist floor systems, with the flooring to go on top. Delivered to site anywhere in NSW.
Two kinds of floor system
Floor trusses (posi joists)
Open-web floor trusses with timber chords and your choice of webs:
- Timber webs, fixed with nail plates.
- Steel webs, which leave more open space for services.
The open webs leave room to run plumbing, electrical and ducting through the floor. Deeper trusses span further, which can mean fewer supports below. Each truss is made to length for its position, so the layout is checked against your plans before it's made.
I-joists
Engineered timber I-joists, supplied as part of a complete floor frame. They're light, long and straight, they don't shrink or twist like solid joists, and the ends can be trimmed on site, which helps on additions to older houses.
Services pass through the web only where the manufacturer's hole charts allow.
Tell us on the quote form if your engineer has specified I-joists or floor trusses, or if you'd like us to suggest one.
Weighing them up? Read floor trusses vs I-joists.
Where floor systems are used
Upper floors
The upper floor of a double-storey home or duplex, detailed with the wall frames and roof trusses so it all arrives as one package.
Second-storey additions
A new level on an existing house, set at a height that works with the existing walls, roof line and stairs.
Raised and sloping sites
Suspended ground floors on sloping blocks, and raised floors on flood-affected land, from the Central Coast to the Northern Rivers.
Flooring to go on top
We also deliver ALPHAFLOOR, Hebel, yellow tongue, red tongue and blue tongue particleboard, and Scyon Secura for wet areas, so the floor frame and flooring can be ordered together.
Concrete floor panels like ALPHAFLOOR and Hebel are much heavier than particleboard, so tell us early. The floor system is designed for the flooring that goes on it.
What to send us
Floor plans and the structural engineer's drawings, with any set-downs for wet areas marked, the flooring you want, and where ducting and plumbing need to run.
Owner builder? See how to prepare plans for a quote.
Request a quoteFloor system questions
Are floor trusses the same as posi joists?
Yes. Posi joist is a common name for open-web floor trusses. We make them with timber webs or steel webs.
Can floor trusses be cut on site?
No. Each one is made to length for its position, so any change goes back to the design. I-joists can be trimmed to length on site within the manufacturer's rules.
Can ducted air conditioning run through the floor?
With floor trusses, usually yes, through the open webs. Show the duct runs on the plans so the trusses are designed around them. I-joists only take holes where the manufacturer's charts allow.
Do you supply the flooring as well?
Yes. Yellow tongue, red tongue, blue tongue, ALPHAFLOOR, Hebel and Scyon Secura. See flooring.