A bit of a silly question but I gotta ask this. Almost all sections are named such as section AA, Section BB etc.
What do these letters actually represent? How were the letters chosen? Can anyone explain if they are chosen randomly to demonstrate where the section line is cut or if they have a meaning?
SneakyPete
Apr 6, 21 5:02 pm
There's no set rule, and anyone saying what it typically is will be speaking based on their experiences.
Generally letters, numbers, or a combination of the two.
Non Sequitur
Apr 6, 21 5:15 pm
Not almost all as I've never used AA or BB... or for that matter, never used two consecutive letters in anything. All my sections are numbered and occasionally I might use 1a or something like that. Whatever makes sense and makes reading the drawings easier for the poor sap on site is what is important.
Weird question.
tduds
Apr 6, 21 5:25 pm
I see AA, BB, etc. typically in mechanical drafting or shop drawing contexts. That's how we learned it when I took drafting way back in high school. There's no set rules, but I always tried to have some sort of hierarchy (AA is the primary section, BB is the opposite axis, CC, DD etc. work down into details).
Like others have said I almost never encounter it on architectural docs. I try to pick a naming scheme that makes sense for the building and then struggle to keep it coherent.
SneakyPete
Apr 6, 21 5:30 pm
If I recall right Revit's default setup is that views of any kind (including sections) numerically increase from '1' as they are placed on the sheet with the other designator being the sheet designation, so if the sheet the callout is pointing to is A0.01 the callouts would read1-A0.01, 2-A0.01, etc. Super annoying that they don't automatically add a 0 in front, but that's just my opinion.
Non Sequitur
Apr 6, 21 5:42 pm
My current jam is measuring out minor gridlines from major ones... and labeling as such: Aka 2.7 is 70% between 02 and 03... and I will only use 2.5 if it's dead centre.
SneakyPete
Apr 6, 21 6:23 pm
When I see or need to use minor grid lines my first though it renovation. Second is "Well someone screwed up."
Non Sequitur
Apr 6, 21 7:14 pm
We use minor grids for brace frame that don’t take up entire bays or smaller structures within a floor plate.
SneakyPete
Apr 6, 21 7:28 pm
You're nicer than I am.
caramelhighrise
Apr 6, 21 9:47 pm
I'd rather have 10 equal major bays with a X.5 somewhere than have 11 bays of different dimensions.
SneakyPete
Apr 6, 21 9:51 pm
It's all about clarity. I may agree with you on one project and disagree on another.
b3tadine[sutures]
Apr 6, 21 5:42 pm
This is funny on all accounts. I always thought it was A to A, because back in the day I'd see drawings with two heads, one at either end of the section designation, with no tail.
The other funny, is that we put sections on sheets that are coordinated to the grid location on the sheet. So, a wall section may start at A1/A6.2 for instance, B1/A6.2...etc.
sameolddoctor
Apr 6, 21 5:53 pm
For masterplan site sections Ive always seen AA and BB done...dunno why
atelier nobody
Apr 6, 21 8:57 pm
Typically if the sections are labeled that way, the section callouts on the plan views will have a single letter at each end - so if the cutline has "A" at both ends, it is for "Section A-A". I've occasionally seen it done on SD drawings, never on CDs.
Wood Guy
Apr 7, 21 12:21 pm
That's always been what I assumed. Is there ever a case where you might have a section, "A-B?"
atelier nobody
Apr 7, 21 1:17 pm
I've never seen different letters in architectural drawings, but it's common in mechanical (industrial) drafting, where the letters indicate points on the part itself.
My guess is the convention of identifying a section by 2 lettered points originated in mechanical drafting and was brought over to architectural drafting in modified form. (Despite self-identifying as an old greybeard, I'm not actually old enough to remember when drafting conventions were first developed. I do, however, have a collection of ancient drafting textbooks, just because I am a geek that way - wanna hear about my multiple compass sets or my 100+ tech pens?)
atelier nobody
Apr 7, 21 1:20 pm
(...or my half dozen electric erasers, including a couple of the old cast metal hexagonal ones...)
A bit of a silly question but I gotta ask this. Almost all sections are named such as section AA, Section BB etc.
What do these letters actually represent? How were the letters chosen? Can anyone explain if they are chosen randomly to demonstrate where the section line is cut or if they have a meaning?
There's no set rule, and anyone saying what it typically is will be speaking based on their experiences.
Generally letters, numbers, or a combination of the two.
Not almost all as I've never used AA or BB... or for that matter, never used two consecutive letters in anything. All my sections are numbered and occasionally I might use 1a or something like that. Whatever makes sense and makes reading the drawings easier for the poor sap on site is what is important.
Weird question.
I see AA, BB, etc. typically in mechanical drafting or shop drawing contexts. That's how we learned it when I took drafting way back in high school. There's no set rules, but I always tried to have some sort of hierarchy (AA is the primary section, BB is the opposite axis, CC, DD etc. work down into details).
Like others have said I almost never encounter it on architectural docs. I try to pick a naming scheme that makes sense for the building and then struggle to keep it coherent.
If I recall right Revit's default setup is that views of any kind (including sections) numerically increase from '1' as they are placed on the sheet with the other designator being the sheet designation, so if the sheet the callout is pointing to is A0.01 the callouts would read1-A0.01, 2-A0.01, etc. Super annoying that they don't automatically add a 0 in front, but that's just my opinion.
My current jam is measuring out minor gridlines from major ones... and labeling as such: Aka 2.7 is 70% between 02 and 03... and I will only use 2.5 if it's dead centre.
When I see or need to use minor grid lines my first though it renovation. Second is "Well someone screwed up."
We use minor grids for brace frame that don’t take up entire bays or smaller structures within a floor plate.
You're nicer than I am.
I'd rather have 10 equal major bays with a X.5 somewhere than have 11 bays of different dimensions.
It's all about clarity. I may agree with you on one project and disagree on another.
This is funny on all accounts. I always thought it was A to A, because back in the day I'd see drawings with two heads, one at either end of the section designation, with no tail.
The other funny, is that we put sections on sheets that are coordinated to the grid location on the sheet. So, a wall section may start at A1/A6.2 for instance, B1/A6.2...etc.
For masterplan site sections Ive always seen AA and BB done...dunno why
Typically if the sections are labeled that way, the section callouts on the plan views will have a single letter at each end - so if the cutline has "A" at both ends, it is for "Section A-A". I've occasionally seen it done on SD drawings, never on CDs.
That's always been what I assumed. Is there ever a case where you might have a section, "A-B?"
I've never seen different letters in architectural drawings, but it's common in mechanical (industrial) drafting, where the letters indicate points on the part itself.
My guess is the convention of identifying a section by 2 lettered points originated in mechanical drafting and was brought over to architectural drafting in modified form. (Despite self-identifying as an old greybeard, I'm not actually old enough to remember when drafting conventions were first developed. I do, however, have a collection of ancient drafting textbooks, just because I am a geek that way - wanna hear about my multiple compass sets or my 100+ tech pens?)
(...or my half dozen electric erasers, including a couple of the old cast metal hexagonal ones...)