search

kbenne / cbecc

Automatically exported from code.google.com/p/cbecc
0 stars 0 forks source link

3.4.1 Semi-Heated Space Sizing/Envelope Specifications Guidelines #788

Open GoogleCodeExporter opened 9 years ago

GoogleCodeExporter commented 9 years ago 
What 90.1 PRM Section(s) are relevant to this issue?
3.4.1 Space Uses

Explanation of issue:
90.1 has 3 space conditioning categories- Non residential, residential and semi 
heated. Issue 777 addresses the distinction between Non residential and 
residential for envelope requirements. Semi heated spaces are defined based on 
heating capacity per unit area for each zone- using the 90.1 baseline envelope 
requirements.

A sizing run would determine the heating capacity for each zone, using the 
Non-res or Res envelope requirements. If the heating output capacity is within 
the range for semi heated spaces, the envelope properties for the applicable 
spaces within the applicable zones in the baseline building, would be changed 
to semi-heated specifications and the sizing run would need to be repeated to 
make sure the heating output capacity is still within range.
If not, the baseline would be modeled with non-res or res envelope 
requirements. 

i.e The sizing run would need to be done twice if baseline heating capacity for 
any zone falls within the semi-heated space heated capacity range.

Proposed resolution:

Original issue reported on code.google.com by supriya....@pnnl.gov on 16 Sep 2014 at 8:04

GoogleCodeExporter commented 9 years ago 
So it's entirely possible to get into a situation where a space with non-res 
envelope is semi-heated, but with semi-heated envelope no longer qualifies as 
semi-heated, and therefore can't really comply with the standard.  

So is this just another example of bad standard writing by SSPC 90.1?  Or does 
the standard explicitly say that the semi-heated space is determined by the 
heating load with a semi-heated envelope?

Original comment by rhedr...@archenergy.com on 17 Sep 2014 at 12:04

GoogleCodeExporter commented 9 years ago 
Yes, it is possible- hence the requirement for 2 sizing runs.

The user's Manual has the following definition-
'The requirements for semiheated spaces apply to semi-exterior envelope 
components while the requirements for nonresidential or residential spaces 
apply to exterior envelope components.'

I believe it doesn't explicitly say that a semi-heated space is determined by 
the heating load with a semi-heated envelope.

Original comment by supriya....@pnnl.gov on 17 Sep 2014 at 9:59