Hi everyone,

I am modeling a building with PTHP units installed. To account for an accurate U-Value of the external wall I want to calculate an area-weighted U-value, part of it is the "regular" external wall, the other section is the PTHP unit itself.

I already called several manufacturers to get information about the thermal
resistance for the heat transfer from the interior to the exterior, but couldn't get any info that would help.
Apparently this is not a topic for them.

Therefore, I was wondering if anybody has information about values that I can apply or if anybody knows any case studies that could help.

Thanks
Tobias