Is this external studwork wall buildup OK?

[Tom]

Hi all - I need to construct a timber studwork gable end that continues on from a Nudura ICF wall over one of our cantilever steels. See pic. The concrete core of the ICF is approx 145mm so I've used the same width timber and plan to put some ply on the outside surface for rigidity, then 90mm PIR screwed on to this to make up the wall thickness to match the ICF. The interior surface would be covered in similar insulation with rockwool between the studs, see diagram in second post. I was going to put a breather membrane over the outside and vapour barrier on the inside. Does this sound right? 

[Tom]

[nod]

Have you considered Met set Metal frame Stronger straighter and easier to work with than timber 

[Russell griffiths]

Why pir, why not eps to match the icf,  

[Tom]

17 minutes ago, nod said:

Have you considered Met set Metal frame Stronger straighter and easier to work with than timber 

No I didn't tbh, but have done the studwork now

 

14 minutes ago, Russell griffiths said:

Why pir, why not eps to match the icf,  

No reason tbh, other than being a better insulator.