you wrote-
>I challenge Bruce or anyone to suggest a wall system which provides
>equivalent thermal and structural performance while maintaining a lower
>environmental impact in terms of embodied energy, manufacturing emissions,
>toxicity, and non-reusable waste generated.
Your right to challenge me, because I did have the impression of bales
rather than blocks ... and I have not read the CMHC "proof-of-concept"
document to which you refer.
However, if the concept of 'Bio-Blocks' is to lock up waste in blocks, it
troubles me to the extent that that waste is a random aggregation of
material including plastics, and wood fiber. Separating the waste will get
us a wall system that is better by the standards you cite above - I am
thinking simply of a wood framed wall with blown in cellulose sourced from
the waste stream. The embodied energy should be lower (because it doesn't
have any plastic) and it thermal performance should be better for the same
reason.
I appreciate that we trying to improve upon the landfill as a destination
for waste (it is a "destination" rather than a stop along the way and
that's clearly a big problem) ... but sorting the waste stream- even
rudimentarily - will give us a better Bio-Block I think.
Have I missed the point again? I often do,
Bruce Coldham
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