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
Hi Everyone,
I'm modeling an office building for LEED that has a DES system. The central
heating and cooling plants are located in the basement of the building, but
also serve other satellite buildings. The DES is owned and operated by a
separate entity (not the building owner).
According to the following excerpt from the DES Guidance for LEED NC 2.2
document dated 3.28.2009 ? ?Also, the requirements in this document apply
only to the satellite buildings served by the central plant building; the
central plant building itself is treated as an ordinary building in
LEED-NC.?, it is our understanding that the building is not covered by the
DES Guidance document (i.e. we are not required to follow the two step
process).
We also think that treating the project as ?ordinary building? means that
all central plant equipment should be modeled explicitly as if the building
had a dedicated plant, prorating capacities based on building sizes.
Does anyone have any experience with this type of situation?
Thanks ahead of time,
Mike Karpman
Mike,
I have used the exception you noted below on several occasions but in my
opinion your building does not qualify. The exception is for when a
dedicated CEP building is to be modeled. While your building does
contain a central energy pant within it, the building is not a dedicated
CEP building due to the office located above. I assume your building
purchases energy from the plant. A CEP building does not typically
purchase energy from itself which is why the exception was created.
Your office is in effect a satellite building with minimal transmission
losses.
Thanks
Seth Spangler, LEED(r) AP