[Greenbuilding] skepticism about mass wall values

Alan Abrams alan at abramsdesignbuild.com
Tue Apr 23 14:44:19 CDT 2013


got into a debate recently about whether claims of high R-values for mass
wall materials such as AAC really hold up in the real world, outside of
Taos, NM, and a few other climates more pleasant than my own.

f'r'instance, a claim was made that a 12" AAC wall has a functional R-value
of over 20, much greater than its "steady state" value of something like
R-12...

...I am not disputing the value of thermal mass, but my sense is that you
should base at least peak load on ordinary R-values, and analyze thermal
mass independently as it might affect annual demand.  With regard to its
value during cooling season--in places where more energy is devoted to
latent rather than sensible load--it seems like mass walls don't have huge
value.

like in "messy" climates such as the Mid Atlantic region.

AA

Alan Abrams*
**certified professional building designer, AIBD
certified passive house consultant, PHIUS*
*certified passive house builder, PHIUS**
*Abrams Design Build LLC
*sustainable design for intentional living*
6411 Orchard Avenue Suite 102
Takoma Park, MD 20912
office  301-270-NET- ZERO (301-270-6380)
fax      301-270-1466
cell     202-437-8583
alan at abramsdesignbuild.com
www.abramsdesignbuild.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.bioenergylists.org/pipermail/greenbuilding_lists.bioenergylists.org/attachments/20130423/8357c256/attachment.html>


More information about the Greenbuilding mailing list