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!
LEEDuser is supported by our premium members, not by advertisers.
Go premium forTo post a comment, you need to register for a LEEDuser Basic membership (free) or login to your existing profile.
A portion of our building envelope is historic. Can we exclude it from our model?
For an existing building, do I need to rotate the model?
Our process load is higher than 25%. Do we have to justify that?
Our local code references ASHRAE 90.1-2010. Should I use that for my documentation, or 90.1-2007?
Can mezzanines open to floors below be excluded from the energy model?
How do I provide a zip code for an international location?
For a project outside the U.S., how do I determine the climate zone?
For a project outside the U.S., how do I determine the Target Finder score?
Do hotel rooms need automatic light shut-off control?
How commonly are the 90.1 mandatory compliance forms submitted as part of EAp2/EAc1?
The Section 9 space-by-space method does not include residential space types. What should I use?
Can the Passive House Planning Package (PHPP) be used to energy model for LEED?
Which baseline HVAC system do I use if my building has no heating or air conditioning?
Our project has a diesel backup generator. Should we include it in our energy model?
Can SHGC be higher in the proposed than in the baseline model?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5867 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
5867 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.