[Bldg-sim] sources for material libraries

Joe Huang yjhuang at whiteboxtechnologies.com
Thu Jan 16 09:07:38 PST 2014


Chip, others,

I was thinking along that line when I posted my comment on this topic last night.  What 
about proposing this as an activity to IBPSA World (?) where interested chapters in each 
country or region would compile their sources of material properties, and if there's 
sufficient interest, the properties themselves?  That would sure beat anyone in one place 
trying to compile data from the whole world, although some central coordination would be 
vital to make sure everyone is consistent in reporting their material properties.  I would 
also like to see that extended to commonly used calculation methods for heat transfer, 
such as for foundation heat flows, infiltration, and two-dimensional heat transfer. In my 
experience in China, every building energy code contains the same standard description of 
of how to derive equivalent U-factors for thermal bridging, which is a significant heat 
loss factor because 99% of the construction is heavy mass concrete, yet in the US only the 
real "nerds" ever bother with thermal bridging (even I don't! ).  I see many benefits from 
such an activity - (1) the local chapters would get clarity on what's different (or not) 
with the conditions in their country, (2) people working across national boundaries would 
be able to improve their modeling (I'm always bothered by people creating "ASHRAE-90" 
models for buildings in non-Western locations, as if all that differs is the climate), and 
(3) we might all learn something new and unexpected.

Joe

Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 108D
Moraga CA 94556
yjhuang at whiteboxtechnologies.com
http://weather.whiteboxtechnologies.com for simulation-ready weather data
(o) (925)388-0265
(c) (510)928-2683
"building energy simulations at your fingertips"


On 1/16/2014 6:58 AM, Chip Barnaby wrote:
> All,
>
> For ASHRAE 1199-RP some years ago (2003 - 2004 ish) I scrounged around looking for 
> material properties.  Attached is a summary of what I came up with for some common 
> materials.  As you can see, there is quite a range of opinion for some properties for 
> some materials (including cases of different values from 2 different places in ASHRAE 
> HOF).  I do not know the source(s) of those differences, in some cases there are 
> probably regional differences and/or changes over time.  Or maybe just bad measurements.
>
> Moisture content is another variable of which we are all becoming more aware.  Lab 
> measurements vs. real-building situations.
>
> Updated versions of some of these sources are probably available.
>
> It would be an excellent project to build up a collection of this sort of info in some 
> shared place, such as the IBPSA-USA Wiki (bembook.ibpsa.us).
>
> Chip Barnaby
>
>
> At 10:48 PM 1/15/2014, Christoph Reinhart wrote:
>> Content-Language: en-US
>> Content-Type: multipart/alternative;
>> boundary="_000_1B23446CBF250648A2FC775DE3FE7E8037C14614OC11expo28excha_"
>>
>> Dear colleagues,
>>
>> We are currently assembling a material library as a basis for energy simulations and 
>> the question came up which source we should use to describe the various thermal and 
>> optical properties of  typical construction materials? A natural answer seems to be to 
>> use the ASHRAE Handbook of Fundamentals 2009 Chapter 26 which lists such numbers. Are 
>> these the tables that "all" of you are using or am I missing an important resource? 
>> What about our Canadian, European and other international friends? Would you scorn at 
>> an ASHRAE library and rather use your own numbers? This data input is obviously tedious 
>> so we want to avoid having to do repeatedly.
>>
>> All the best,
>>
>> Christoph
>>
>>
>> _______________________________________________
>> Bldg-sim mailing list
>> http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org
>> To unsubscribe from this mailing list send  a blank message to 
>> BLDG-SIM-UNSUBSCRIBE at ONEBUILDING.ORG
>
> ---------------------------------------------------------
> Chip Barnaby, BEMP     cbarnaby at wrightsoft.com
> Vice President of Research
> Wrightsoft Corp.            781-862-8719 x118 voice
> 131 Hartwell Ave            781-861-2058 fax
> Lexington, MA 02421 www.wrightsoft.com
> <http://www.wrightsoft.com/>---------------------------------------------------------
>
>
> _______________________________________________
> Bldg-sim mailing list
> http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org
> To unsubscribe from this mailing list send  a blank message to BLDG-SIM-UNSUBSCRIBE at ONEBUILDING.ORG
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20140116/ea6856b7/attachment-0002.htm>


More information about the Bldg-sim mailing list