ASHRAE 90.1-2016 - appendix G. PCI calculation - feedback

In our limited experience, it appears that 90.1-2016 using the BPF is much more stringent, in the 8.5 to 9.5 neighborhood. Especially when architects give us  floor to floor curtain wall for an envelope.  "But this building wants to be transparent..." - and I want to date Heidi Klum.   We are very much in favor of the simplified modeling approach for the baseline that easily allows users to compare performance against multiple standards without rerunning the energy model.  The downside is all the ECMs for the regulated energy use are baked into the BPF.  If the user isn’t modeling the same level of savings performance for, say a mandatory ECM, as what was modeled in the prototype model to create the BPF, you are starting at an energy deficit.    We need greater transparency and guidance on how the various ECMs were modeled for each building type in each climate zone to understand how that should be reproduced in our proposed models in the various modeling software packages in order to have any level of equivalency.   There is also the issue of exceptions.  We are not aware of any means to account for an ECM that is already baked into the BPF that may not be applicable to a particular project due to an exception to the requirement.

Adam, great post, thanks for asking the question.  I agree with you and Kim.  I am at a 9 - 9.5. In NYC projects have had the option to use PCI or Section 11 for code compiance since the 2016 Energy Code (NYC adopted the PCI method as an option in 2016).  We have yet to use PCI as the compliance metric as almost universially Section 11 is more forgiving.  This is also true in my brief experience with the 2020 NYC code (and LEED v4.1). Curious if others have the same experience.