Building a 2-story home in Austin, TX. What insulation is best?
The roof is already insulated with R-19. There is no attic in this home. The exterior walls are part stone, part constructed stucco/plaster-like material.
I would suggest a bio-based foam.
Depending on what structure is, assuming wood, might affect your choice of closed vs open cell.
For more information:
Read "We have inadequate wall insulation. What is the best approach to insulate our walls?" a Q&A answered by Mike Holcomb.
Also, read our insulation backgrounder "Choosing the Best Insulation Delivers Energy Savings."