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Sustainable design; Energy Evaluation, EcoDesigner and EcoDesigner STAR

Moderators: Karl Ottenstein, LaszloNagy, ejrolon, Barry Kelly, gkmethy

By Tom Krowka
#207911
Anyone know where one can find additional values of materials in "k", thermal conductiivity, density, and heat capacity for typical materials in the US......like 1/2" gyp board, 5/8" fire rated gyp. board, etc.

Also, the materials library in Ecodesigner are hard to understand. For instance, why are there four different types of concrete.....four different k values.

Some help with the material catalogue would be good. Most materials I look up online have U values, not k. How can I translate between units.

It seems like a good tool, but without the capability to accurately set up material assemblies.......well it will be garbage in.....garbage out.
User avatar
By TZG_Kevin
#207994
Let me share my experience Tom,

When I (Graphisoft AUS) was working on ArchiCAD 16 Australian Template with David Shorter (AUS Strategic technical Manager), We had exactly same problem. "thermal conductivity" values in INT version of ArchiCAD wasn't correspond to the values in AUS.

I think, the differences are coming from, testing conditions, such as climate, location, method, and "who is testing" :) so I started to collect local datas from:
1. Local simulation tools' database
2. Local manufacturers specification (picked couple of major company's data and I used the mean value)
3. Government standard values.

It took me about 2-3months to get typical AUS construction database and still working on this to update this values in the next version.

In terms of density, and heat capacity, to be honest, It was difficult to find relevant indicators, so I decided to reference the values in the standard Archicad database. (but I found most manufactures had this data in their specification).

as a result, We have completed the first version of thermal value localisation into AUS standard template.
We then created new fills with local "k" value and deleted some cover fills with no thermal values.

When I saw Bimcomponent feature in AC16, I was hoping to have similar concept of cloud system where we can post thermal values and share them. Eventually, manufacturers will be in charge of this database and can promote their products at same time.

Hope this information helps,
Attachments
AUS k.png
AUS Standard thermal attributes setting.
By Tom Krowka
#208000
So........really doesn't help the immediate situation. Have looked at the U value override......but not really tried it out. I think one has to have the BEM built with composites, then are able to assign a U value to the composite via the override.

Have you any insight into this?

Thanks.
User avatar
By gpowless
#208022
The most reliable source for material u-coefficient values would be ASHRAE ( http://www.ashrae.org/home/ ) but I have always found their stuff a bit pricey. Even still if you need standards and accuracy they would have the publications to back it up.

Another source that I used to refer to years ago was the American Graphic Standards. My older copy contains an number of materials and U-values.

Hope that helps.
By Tom Krowka
#208043
Unless I'm not seeing something, there is no way to insert U or R values in the material catalogue.
You can, however, insert the U or R value for an entire wall, roof, etc. assembly once you have the model built, and open the Energy Evaluator. I believe I will employ that workaround.
User avatar
By Barry Kelly
#208065
Tom Krowka wrote:Unless I'm not seeing something, there is no way to insert U or R values in the material catalogue.


Not in the materials setup.
But if you go to the fills setup then you will find a "Thermal Properties" section there.

The materials are just an image/colour applied to the surface of an element.
It is the fill used in plan/section that contains all the thermal information.

If you set up all your fills with their thermal properties then your composite walls will automatically get values based on those settings (if they use those fills).
If not then you will be prompted to add the values in (you will see a yellow triangular warning symbol).
You can select that and then click on the "3 dot" button to add propeties to the fill or you can click on the red padlock and override the values for the entire wall.

Barry.
User avatar
By MMontgomery
#208414
I just finished the Eco-designer webinar a few minutes ago and this was covered somewhat, but not specifically..

I am working on our company template to include the thermal values of various materials we typically use such as sheathing, batt insulation, gypsum board, etc. According to the webinar, the Materials Catalog cannot be edited (making it rather useless for the most part), so creating standard thermal properties needs to be done in the 'Fill Types' Thermal Properties dialogue.

Not being familiar with thermal property calcs, would a single set of Thermal Property values for say, the 09|Gypsum Board fill, work for the various thicknesses of gypsum board, or would I need to create a separate fill using separate values for 1/2", 5/8", 3/4" gyp board?

Would this hold true for all materials, or are there some materials that have properties that are not consistent through various thicknesses?

My assumption is that a single fill would be appropriate but I would like to verify that.

Another problem is that I have a very difficult time trying to find the thermal properties of many products. It might be my ignorance of the subject, but many times it may give Heat Capacity and Thermal Conductivity but not Density or any combination like that. Anyone having luck finding all the values they need to accurately fill out the information?


Thank you!

Mike
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By TZG_Kevin
#218826
Thanks you so much for the precious information Laura!

With my experience and the others, Many simulation users are in dilemma with these values because the thermal property values are all different by who tests it, where they take the test, how, and other testing conditions.

I have tested few standard composite structure's U-value between Ecodesigner(energy Evaluations), local manufacturer's data and Australian standard value and they are all different by upto 30%.

Again, thanks for the reference information, I will update some of AUS thermal properties in the next template edition.

Cheers,
#218827
Yes, it's a little disconcerting that there doesn't seem to be a reliable database. And 30% is a significant discrepancy! I have not had the opportunity to test EcoDesigner to the extent to know how this affects the output.