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CBECC-Com Issue - Status Classification #945

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago 
Version = 2013_3b-beta_700

Category = Other

Issue Summary:
List the steps taken to produce the error. For example:
      1. step 1 - open the file
      2. step 2 – Run the file
      3. step 3 - software produces error relating to the UndergroundFloor Ruleset.

Hi,

I am struggling to figure out how to assign “new”, “altered” and 
“existing” to objects in CBECC-Com and I can’t find any help anywhere so 
suggest whether my assignment is correct. I have a project that is a warehouse 
that was roughly 50% conditioned by a PVAV system and the other half was 
technically conditioned but just had two gas furnaces in the rest of the space. 
The project is undergoing a core and shell renovation applying for envelope and 
mechanical permits with the tenant to complete the lighting compliance upon 
moving in. The original PVAV system will remain and there is another PVAV unit 
being installed to condition the space that was previously conditioned by 
heating only. What I don’t understand is should the original PVAV be 
“existing” or “altered” because the terminal units are technically 
changing? Should the new PVAV be “new” or “altere””? It was 
previously conditioned so it’s conditioning type hasn’t changed, but the 
system is completely new – along with a new boiler and HW loop for reheat. As 
the lighting is not being permitted, should I be specifying the lighting as 
“new”, “altered” or “existing” in order to set it equal to the 
baseline as the ACM states? If I do it as “new”, then I need to select the 
place mandatory daylighting controls option, but if that’s the case then the 
report will be covered with the text saying that it isn’t usable for 
compliance. Moreover, the floors, walls and roofs of the building are not being 
changed at all, but there are places where new windows will be put in. Are the 
walls then “existing” and the windows “new” or are the walls 
““altered”” and the windows “new”? I have a similar scenario with 
skylights in the roof. Is there anywhere I can find an explanation of how to 
classify the objects in the model?

Currently, I have the model as I see I think makes sense but I am running into 
errors as shown below - the PVAV is set to “altered” and the slabs are 
“existing”, which I think is the right classification for them. The only 
way I can get the simulation to run is if the slabs are “altered” or the 
PVAV system is “new”. I have attached the model and if you could help me on 
this model, as well as provide some information on how I should be classifying 
the statuses of the objects, that would be incredibly helpful.

Original issue reported on code.google.com by f.le...@gmail.com on 24 Feb 2015 at 12:37

GoogleCodeExporter commented 9 years ago 
Status is assigned somewhat differently for different aspects of the building, 
as follows:
• New
o   Window that increases window area
o   Walls that increase floor area
o   Lighting systems that increase lighting power
o   Added or replaced HVAC components
• Altered
o   New window that replaces an existing window 
o   New wall that replaces an existing wall
o   Modification to an existing wall
o   Lighting system modifications that do not increase lighting power
o   HVAC – not applicable
• Existing
o   Unchanged windows
o   Unchanged walls (thermally)
o   Unchanged lighting systems
o   Unchanged HVAC components

Also, it is important to remember that status has no effect on the proposed 
model, it only affects the baseline.  This is why “Altered” does not apply 
to HVAC systems.  The rules are not able to mix new and existing components in 
a single system.  An HVAC system in the baseline must be entirely new or 
entirely existing.  In the situation you describe, the new PVAV system is 
entirely “new”.  The existing PVAV will need to be “new” if the reheat 
coils are changing heating type or efficiency, but the degree of change to an 
existing HVAC system that makes it new is not well defined.  My basis is if the 
thermal performance has been improved, it becomes “new.”

For the lighting, I would use the default LPDs for the space type and show the 
mandatory daylighting controls only, but then explain the you are not 
submitting for lighting compliance.

Original comment by rhedr...@archenergy.com on 24 Feb 2015 at 3:01