I think technically that is a gallery because of the supports then (regardless of modernity). But I think you're trying to pull a name for a very specific application, which may or may not have a name.

would this be a cloister?, or that only applies to the covered rectangular arcade at the ground level only?

"Cloister" refers to the function, not the architecture, so this could be a cloister but probably isn't. I'd call it a "gallery" surrounding an atrium. It's not an "arcade" because it has a straight lintel, not arches. I think it might technically also count as a "loggia", although I would typically only use "loggia" if it were outward-facing. Cloisters, galleries, arcades, and loggias can all be on floors above the ground floor.

Except for (most, not all) theater balconies, it's not a balcony if it's supported on 3 sides, and it's never a balcony if it's supported on 4 sides as this one is.

You can have a single-story atrium house. There is no requirement that they be multi-story. Many depictions of the ancient Roman atrium houses are single story

This was straight from UBC/CBC CH2. You are comparing the Roman Pompeian houses as a counter example to the current building codes?

Yes. There are plenty of single story atrium houses in contemporary styles. If their definition says two stories are required they need to change it.

i could see stasis making the argument to his AHJ "but in first century CE Pompeii they did this thing and the code official allowed it"

@Volunteer, have you successfully obtained a permit and built an atrium in a residential application? Is this from your professional experience with precedents or you are just arguing the definition of 'atrium'? Perhaps those houses didn't label their vertical opening space an 'atrium' and called it something else. If you have done this yourself, then you can certainly share how you worked through the permitting.

@Stasis, many modern houses have atria (by the traditional definition) - try Googling "Eichler Homes" for many examples. The fact that these atria are not defined as such in current Codes certainly doesn't mean they can't be built, nor does it mean "atrium" is not still the correct term.

Speaking as a former Plans Examiner myself, any plan checker or inspector who sees the word "atrium" on a set of SFR plans and assumes that means it has to meet the Code requirements for a multi-storey atrium is an idiot.

I'll continue dope;

[BG] ATRIUM. An opening connecting two or more stories other than enclosed stairways, elevators, hoistways, escalators, plumbing, electrical, air-conditioning or other equipment, which is closed at the top and not defined as a mall. Stories, as used in this definition, do not include balconies within assembly groups or mezzanines that comply with Section 505.

atrium (n.)
1570s, from Latin atrium "central court or first main room of an ancient Roman house, room which contains the hearth," from Proto-Italic *atro-, sometimes said (on authority of Varro, "De Lingua Latina") to be Etruscan. Watkins suggests it is from PIE root *ater- "fire," on notion of "place where smoke from the hearth escapes" (through a hole in the roof). De Vaan finds this not very compelling, "since soot is black, but not the fire itself," and prefers a different PIE root, *hert-r- "fireplace," with cognates in Old Irish aith, Welsh odyn "furnace, oven," Avestan atarš "fire."

The appurtenance of atrium depends on the interpretation that this room originally contained the fireplace. This etymology was already current in ancient times, but there is no independent evidence for it. Still, there is no good alternative. [de Vaan]

The anatomical sense of "either of the upper cavities of the heart" first recorded 1870. Meaning "sky-lit central court in a public building" is attested by 1967.

Residential building codes do not define atrium. Atriums in a one story is both anachronistic and complete archispeak for an interior courtyard.

oooooo, a garage. how fancy

Plans are so like you, where's the sections at?

The absence of stairs in the floorplans pretty well indicate they are for single-story atrium homes, as noted by the architects. But maybe not in whatever world you inhabit.

Volunteer, Those plans don't mean crap to me as they are not approved permit drawings. They look like example images from 'Architectural Drafting and Design' by Alan Jefferis. As this is a forum for design professionals, I'd hope to see someone to actually provide relevant examples and deeper insights based on one's professional experience. b3tadine[sutures] sort of did it for you. The point of my post was clear. To re-iterate, It was about architects need to do their due diligence in researching the name of the space for its code compliant definition and any associated requirements.

b3tadine[sutures],

Sorry, my response got truncated.. Thank you for your insights. I've never done residential projects and in fact never read the residential code. If the residential code doesn't define an atrium, then can you also get away from fire/smoke requirements as well in a residential application? If you don't know top of your head, that's fine.. i'll look it up. I'm genuinely interested.

See 2021 IBC, 404.1 Exception and 712.1.2. I'll send you an invoice for my consulting fee.

In the 2019 CBC, the relevant references are the words, "and where permitted by Section 712.1.7," (although I believe it's an error and reference should be to 712.1) and 712.1.2.

You are, of course, welcome to call an atrium "George" or "Fred" on your drawings if you'd like - they're your drawings.

i'm not disputing the permitted use of the atrium, so Chapter 7 isn't as important to me. Just wanted to know the smoke/fire requirements.