Joist Options

[richo106]

I am starting my renovation/extending/remodel project shortly where i will be adding another floor

 

I was planning on installing MVHR system throughout so was going to go the posi joist route

 

But I am toying with the idea of not installing MVHR now due to not probably getting the ACH/insulation levels where they need to be. But installing some form of MEV instead

 

Is it worth just installing standard joists now? Is there a big difference in cost?

 

I will need to run a couple of ducts (probably 125mm) through some joists, is there a way this can be done through a normal joist with support plates or something? Would only need to do 2/3 

 

Thanks in advance

[markc]

Joist selection comes down to span, floor loading, bounce, sound transfer plus ease/practicality of installation of services etc.

assuming the span is pretty average then solid joists are the easiest and cheapest for a small job. Cutting out big holes can be done but then moving to I’s or pozi’s is easier.

I joists can be fabricated on site or local joiners shop pretty easily, just add a percentage over factory produced spec as tolerances and glue is often better and more controlled.

[nod]

We used I joists on our previous build 

Main reason being was that they where a third cheaper than Posi

I regretted my decision as soon as I started first fix plumbing 

Ive used Posi this time 

[markc]

Oh yes! 1st fix electrics aren’t too bad on I’s but pozi’s make plumbing or conduit (protected fire alarm cables) runs so much easier

[Russell griffiths]

With the cost of timber I think solid timber will not be a lot cheaper.