Insblok 19

[Pcoulton]

I know this is not whats designed for. But, the price is right. $25 a bundle.
What is estimated R -value of Insblok 19 3" sheets.
we were thinking about using for attic insulation.
thanks

[JRPizza]

Wow, that seems to be a very low price! Since this material is intended for very high temperature applications, all of the data I have seen for heat transfer is for 400F and above.