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NC-2009 EAp2: Minimum Energy Performance

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Decreased U-value increased Energy Consumption

August 13, 2014

Omar Elrawy

Green Building Consultant | Researcher
GreenA Consultants

LEEDuser Basic Member

56 thumbs up

August 13, 2014

Dear all,
I had a reviewer comment for my basecase walls and floors assemblies that were modeled with U-value higher than the appendix G values by a mistake, however, after correcting these values to the lower values the Energy consumption did increase unexpectedly, knowing that I'am modelling in a 2A climate zone.

I need to know if I should keep this result as it is for the final submittal; or try describing/ justifying the reason for this increase in the basecase energy consumption to the reviewer?

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Marcus Sheffer

LEED Fellow
7group / Energy Opportunities

LEEDuser Expert

5909 thumbs up

August 13, 2014 - 3:01 pm

Yes you should provide an explanation. Is the building internal load dominate? If so adding insulation can often increase energy use.

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