Insulation for thin joint block + block

[WWilts]

Question: Can Dritherm mineral wool slabs be used with block inner and outer leaves, if thin joint blockwork is used? 
Any serious potential downsides?
Any more economical / buildable way of cavity wall insulation if thin joint blockwork used for inner & outer leaves?

Thanks

Context: Need to control costs,  for better or worse. Not forever home.

Non-masonry options ruled out for various reasons. Site foreman, scaffolding costs etc all increase with duration of build/delays. So, for better or worse, duration of build is important consideration.
SAP pass with wall U value 0.25, airtightness 4.0, floor over slab insulation 100 mm Celotex
 

 

 

[A_L]

@WWilts^, Dritherm Cavity slabs are rated for 'full fill'. Silver/Graphite/Grey bonded EPS bead, conductivity 0.033/0.032W/mK with any block with a thermal resistance less/equal to 0.18W/m^.K  would get to your U-value. i.e. 100mm block/100mm bonded bead/100mm block. It could possibly be top filled.

[PeterW]

Bin the thin joint if you want fast (as I have said before)

 

Are you sure that is the wall figure or the weighted wall figure when including the windows...??

[WWilts]

7 hours ago, PeterW said:

Are you sure that is the wall figure or the weighted wall figure when including the windows.

My guess is wall figure