topic Re: U Values in Sustainable design

U Values

Anonymous — Thu, 11 May 2023 08:48:49 GMT

Please forgive this newbie question:

I can put the W/mK against each element.
I can use these elements to create a composite surface.
(Except I can't make an element layer that combines timber and insulation)

... so where can I see the 'U' value of the composite?

... and if I use this composite with some openings in it, where can I see the aggregated 'U' value for that element?

Re: U Values

David Shorter — Tue, 05 Jan 2016 01:26:59 GMT

HI
you have probably found this already but if not you can find the U values of the surrounding structures by using the Energy Evaluation tool found at the bottom of the Design Menu
Hope this helps

Re: U Values

Anonymous — Thu, 11 Feb 2016 13:16:09 GMT

Thanks for the kind information

Re: U Values

Anonymous — Mon, 28 Mar 2016 08:00:55 GMT

What is the purpose to know the composite wall U-value? If this is for energy demand evalualuation, it must be done manually in ArchiCAD. The tools are not working correct in case of composites, especially in case of ventilated facades and frame walls. The best solution is: to make calculation manually or with special software and then use the U-values applying them to non-composite walls. In addition thermal bridges should be considered. For openings it is quite simple, U-values can be defined in the object properties.
By the way, the tool for thermal bridges is quite simple to use, calculates proper values, but not the actual thermal bridge PSI value. The real value can be found by isolating parts of structures involved in thermal bridge and finding their PSI values.