[Cob] living roofs

[yew]

Karen Mason wrote:

 >In Becky Bee's book she states that when wet, a
 >living roof will not be an effective insulator. In contrast,
 >the book written by the UK couple states that a living
 >roof is very insulating. And, I assume that in England
 >their live roofs are wet all the time. The design of our
 >roof and cost will be dependent on whether we insulate
 >or not. We would prefer to not insulate as we have also
 >realized that insulating with non-toxic materials will be
 >challenging.

Living roofs don't have meaningful insulation value.  They do help 
moderate temperatures, though, so they're great in the summer.

Is this a roof on a permitted house?  What kinds of restrictions are you 
facing?  Insulation doesn't have to be expensive.  Tony Wrench used 
straw to insulated the roof of his roundhouse (sandwiching canvas, 
straw, waterproof membrane, more straw, and finally sod):  
http://www.thatroundhouse.info/how.htm

Brina