Forum discussion
NC-2009 EAp2: Minimum Energy Performance
Does anyone know if there was a point where the IECC became more stringent than ASHRAE 90.1-2007 that is generally accepted by reviewers or is it always necessary to upload justification that the code you're following is more stringent? I hope the question makes sense. Thanks!
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Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
August 10, 2018 - 2:34 pm
Overall stringency is always a relative comparison. Innumerable variables enter into the determination. Any percentage of stringency improvement is always a very rough average and may not be at all accurate in certain climates and with certain building types. I have not seen an overall stringency comparative study between the two. Most of the evaluations performed are comparisons, not stringency evaluations.
My understanding is that generally the latest IECC is generally considered to be overall equivalent to the latest version of 90.1. IECC 2009/90.1-2007; IECC 2012/90.1-2010; IECC 2015/90.1-2013; IECC 2018/90.1-2016; etc. There are obviously discrepancies and codes change so I think that it is generally necessary to continue to note that the code requirement is more stringent for any particular item in question.
Do you have something specific in mind beyond an overall stringency comparison?
Jason Cocek
August 10, 2018 - 4:15 pm
I realize now I should have posted this in the CI EAp2 forum. I was thinking of the mandatory provisions and prescriptive requirements of ASHRAE 90.1-2007. Do I need to provide my own item by item comparison against IECC 2015 (the local code) as documentation or would one of those comparisons (IECC 2009/90.1-2007) that has already been done suffice?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
August 13, 2018 - 10:57 am
Perhaps you could post the question to that forum and I will try to answer it there. Please cite the Option you are considering in CI EAp2.