Any further comments on this?
The various proprietary suppliers of EWI systems do charge a lot for their non-standard-size (e.g. 500x1000) insulation boards, which I think are invariably 'aged'. It's tempting to buy 8x4s of standard insulation and cut it up, but I for one think there's good reasons to pay up for the proprietary suppliers' boards, certainly when it's going to be rendered. We don't want to see 'giant brick' effect after a couple of years or less, esp knowing the shrinkage gaps that will lie behind.
But what about EWI that's going to be clad e.g. with boarding. Not sure that's really called EWI? I have found myself treating it differently, as ordinary builders work, using those 8x4s of insulation board - seamless with same on the roof slopes. Of course no one ever sees the telltale 'giant brick' effect but I guess the shrinkage gaps are there. Or are they? We glue the boards with roofing contact adhesive to continuous OSB, and we foam all the joints however tight they are. or we do both of those in one go if using foaming polyurethane glue.
In this latter non-rendered case, should be be using aged insulation boards? If not, if we're doing enough to ensure no shrinkage gaps, then why must the boards be aged when rendered?