40# felt vs. TG-2

[quote=“dianej1”]

MBTechnology also has an SBS modified underlayment called layfast TU-35. For tile most go with their TU-43 which is heavier and you don’t need to double ply it.[/quote]

[quote=“swmrdrn”]the city will only allow me to use wood shake or Cedarlite.
[/quote]

Interesting. Neither sounds like a good choice for wildfire and earthquake country? Can the shakes be effectively fireproofed?  How much do those tiles weigh? Why don't they allow  metal?