Straw Bales as Ceiling and Attic Insulation
I am an architect in Rochester and may be able to answer your questions.
As for straw ceilinig insulation. Sounds like a great idea. The draw back is that the ceiling structure will now need extra capacity for the structural loading. Not a big deal, but a littel extra capacity will be needed. You will need to protect the straw with a 15 minute fire barrier (1/2″ drywall, 5/8″ T&G wood, plaster, etc). You’ll also want to make sure you have propert ventilation/thermal break between straw and underside of roof decking to prevent ice dams.
Depending on your existing structure and attic space, you may find you are better off paying the $2.20/SF for some open cell bio-based spray foam insulation.
Christopher Costanza, RA, AIA, LEED AP