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Floor Area does not match its construction area

asked 2015-08-04 20:34:19 -0500

hugopft's avatar

I am modeling a Building and I am getting the following warning: * Warning * BuildingSurface:Detailed="0B_ARQUIVO GERAL - FLOOR:A", underground Floor Area = 50.97 * ~~~ * ..which does not match its construction area.

I have already checked the areas of the space pointed out by the program report in the Sketchup (where I modeled the building) and in the Openstudio, and in both cases the areas values are matching with the value shown in the ERROS AND WARNINGS REPORT. So, Why I am getting this messange? Is it ok, Imean, can I stay with it or can I have wrong results because of that?

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I assume you don't have any sub-surfaces in this surface? If you did you would be seeing warnings about that as well. When EnergyPlus runs does the resulting building area match what is expected? Could it also be something weird like a non/level floor, never tried that, but it if floor area was measured orthogonality it wouldn't match the surface area.

David Goldwasser's avatar David Goldwasser  ( 2015-08-05 10:22:17 -0500 )edit

Yes @David Goldwasser, the area matched as expected. I checked the areas in all the ways possible, and that is why I can not understand the meaning of this warning.

hugopft's avatar hugopft  ( 2015-08-06 07:30:19 -0500 )edit

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answered 2015-08-19 14:29:39 -0500

This error occurs when the surface outside boundary condition is GroundFCfactorMethod and the area in the corresponding Construction:FfactorGroundFloor does not match the area of the surface.

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ok @MJWitte . So, is it right? I mean, should I leave in this way and justify to the LEED reviewer that I am using GroundFCfactorMethod or there is a way to fix it? In case it is ok, my question is: Can I trust my results, I mean, this warning is not saying that my results are wrong because of this incompatibility?

hugopft's avatar hugopft  ( 2015-08-19 16:51:47 -0500 )edit

Doesn't sound like it's right. Why is the area in the Construction:FfactorGroundFloor object different from the floor surface area?

MJWitte's avatar MJWitte  ( 2015-08-21 18:26:15 -0500 )edit

Yes @MJWitte, and this is my question: how to fix it? I ask if it is right or not, because sometimes, an warning does not mean that I can not trust my results, but I understood that is not the case. Thanks.

hugopft's avatar hugopft  ( 2015-08-21 21:34:19 -0500 )edit

@hugopft I am not sure exactly how OpenStudio manages the C-factor and F-factor constructions, but I would guess that you need to create surface-specific construction objects in the Constructions tab and then assign them to their corresponding surfaces by drilling down to each floor surface in the Facility tab.

MJWitte's avatar MJWitte  ( 2015-08-25 10:24:07 -0500 )edit

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Asked: 2015-08-04 20:34:19 -0500

Seen: 262 times

Last updated: Aug 19 '15