Cob: RE: Re: Thermal Mass and R-values

[Michael Saunby]

On 25 July 1999 17:06, Mike Carter and Carol Cannon 
[SMTP:cobcrew at sprynet.com] wrote:
[SNIP]
>   Consider
> also two samples that have the same density but in one, the insulating
> material is in a solid layer in the middle instead of being dispersed 
evenly
> throughout.

OK, how do you suggest folks do that?  What mathematics should be applied 
to these types of problem? How does one go about considering the degree of 
comfort/discomfort felt by occupants of a building?


Consider the possible combinations of 10m x 2m x 0.1m of polystyrene or 
some other insulator and 10m x 2m x 0.1m of brick or some other structural 
material, e.g. cob. To build a wall of 10m x 2m x0.2m how should these 
materials be combined?  Which will be the most comfortable? Which will use 
the least energy to heat?  Which will use the least energy to cool? Is the 
answer the same for all?  How DO builders calculate this today? Are they 
getting the right answers?  Should the costs of the materials be conside  
red?  If so what would be the trade-off between structural material, i.e. 
something that will hold the roof up, vs. insulation which will just 
collapse under the weight?

For myself I would have no interest in a building that required energy to 
cool it.  I'm prepared to heat in winter but at other times I expect 
natural heating, cooling, and ventialtion to be sufficient.

Michael Saunby