[Greenbuilding] [BULK] FW: Aerated Autoclaved Concrete

[Corwyn]

On Feb 09, 2008, at 17:43, Jeannie Babb Taylor wrote:

> Hi, Corwyn.  I will respond to some of your points below.
>
> C:  Well I don't think concrete classifies as green.
>
> J response:  Typical concrete is not considered green because of the 
> cement
> content.  Cement produces greenhouse gases.  But if you look at the 
> cement
> content of AAC, it is extremely low.  Something like 20% of the dry raw
> ingredients -- stirred up with a whole lot of water and then aerated.  
> The
> finished material is 80% air.  By my math, that makes cement less than 
> 4%
> the finished product.  The main ingredient (other than air) is sand.

I don't consider 'air' part of the ingredients.  Wood is mostly air.   
The question to me is 'how much concrete is in the house, and would 
something else be better.  I don't know the answer to that one yet.

>
> AAC certainly classifies as a green material.  Check out LEED or any 
> other
> rating system and you will find it there.  In fact, our AAC blocks are 
> used
> in the Alberici headquarters, which is acclaimed as the most green 
> building
> in the world!  It has a platinum LEED rating.
>
> C:  Why would it be so unpopular here for 80 years if it did work?
>
> C:  I really hate the 'they do it in europe, it must be great' card.  I
> hate even more the 'it's popular therefore it must be great' card.
>
> J response:  Corwyn, don't you see how you're contradicting yourself?  
> You
> call it a "card" when I note its popularity, even after you try to 
> tear it
> down because of unpopularity here.  At least be consistent.  (Or maybe 
> I'm
> confused and someone else said that first part??  It's hard to follow a
> response to a response to a response.)

No, I am not contradicting myself.    I was pointing out how the 
original post contradicted itself.  I can hate both types of illogic 
without contradicting myself.

I saw the original post as saying:
1) It is unpopular here, therefore here sucks.
2) It is popular in Europe, therefore it is good.

Both of these are inappropriate metrics for evaluating the use and 
green properties of a material.  Let's talk R-value per embodied energy 
or some such.

Sorry, that I was unclear.

Thank You Kindly,

Corwyn