[Strawbale] bubble foil

[Nancy or David Gray]

Hello Don.  Thank you for the numbers.  I was wondering about the performance of foil wrap all by itself.  I would never use it under a slab and would never depend on it to replace insulation anywhere.  I hope you did not think that.  I was only suggesting it as a final layer below the insulation and with an air gap to allow reradiation from above, but mostly to reflect heat from what would have been an exterior space in that particular building, a raised second story above unconditioned space.  
I respect your knowledge, so where would you use foil?  And what do you think of its use on rigid foam?  How do you like to reduce radiative heat?  Best wishes, David Gray