Friday, 21 September 2012

Posi-Struts (a response to BruP)

Firstly, thanks BruP for your comments on our blog (see post 8/9/12) regarding posi-struts. I did some research. The diagrams below explain what posi-struts are. I also read the engtruss website you supplied (thanks again - a good reference). BruP you're right. An advantage of posi-strut is that it's easier to run services (eg pipes) through the open space.

You're aware we had our private frame inspection today. I asked our inspector about the pros and cons of posi-strut and whether it would have been better for this build. His opinion is that while it is easier to run services through posi-strut joists, for good tradies, it's not very difficult to drill holes through the standard joists (such as the joists used in our build) to run services. Further, he suggested the standard joists could actually be better because sometimes posi-strut can creak and squeak and actually make more floor noise under foot. He also offered that a large percentage (I think he said 80%) of the better builders will still be using the standard joists as opposed to posi-strut.

It's good to hear you are not paying $5K upgrade for posi-struts. If you were, based on advice I received today, I'd be telling you to save your money. You could possibly just clarify with CG what the $5K is for, then again, ours is not a custom build so I would imagine things would be different between our builds. I wonder why CG custom builds use posi-strut?

Thanks for drawing our attention to posi-strut. I would not have known to research if you had not made your comment. Good to be communicating. Cheers.

Posi-Strut & Posi-Plus
Posi-STRUT® is an open web truss system that combines the strength of steel with the flexibility of timber for custom made systems that will meet the exact requirements of your job.

The joists used in our build (see below)


  1. We are also doing a custom build & have been advised that we have to pay 5k for the custom joists

  2. Hi Moxie

    I have asked my administrator at CG regarding this 5K upgrade and still waiting whether this includes the posi strut joist. From my understanding the upgrade is "standard" to all custom homes.
    My concern with not using posi strut is running the duct system for the heating and cooling after handover - I deleted my gas heating because I wanted a refrigerated inverter cooling and heating. CG charges close to twice as much in comparison to air conditioning specialists I asked around. One guy did mention that without posi strut joists it might be a big job to run the duct system which would include dismantling ceiling etc...