[Cob] Lava Rock

[Janet Standeford]

  The other folk that built with pumice cob in Victoria have a website 
www.eco-sense.ca and I think there is something on there about the 
R-value of their cob, as they are all set up with sensors in the walls.

Actually, they claim .5 R value for regular cob and 1 per inch for 
pumice cob but actually the energy model done for regular cob is R19 for 
20 inches so i don't think the additional hassle of pumice really adds 
anything unless their cob mix is vastly different.