I agree Robert!

The push to clarify the boundaries between LEED, the 90.1 mandatory requirements, and demonstrating compliance with 90.1 as a standard was driven by other language. The foundation of your query is sound: these vestibule requirements are indeed part of the mandatory requirements LEED mandates through EAp2.

Perhaps by lucky circumstance (?), I often find myself advising my architects and envelope designers what 90.1/IECC truly require for a given project & jurisdiction, and more often than not I tend to find one or more building entries fall into those 90.1 exceptions. There are certainly circumstances and projects that will require a vestibule at each entry, and I don?t mean to say that isn?t a possibility. I merely hope to encourage those approaching this to thoroughly review those passages, so that nobody misses an applicable exception.

Regards,

NICK CATON, P.E.