Editing Paper size (section)

==== Architectural sizes ====

[[File:ARCH PAPER SIZES v3.svg|thumb|right|A size chart illustrating the Architectural sizes]]
In addition to the system as listed above, there is a corresponding series of paper sizes used for [[architecture|architectural]] purposes defined in the same standard, ANSI/ASME Y14.1, which is usually abbreviated "Arch". This series also shares the property that bisecting each size produces two of the size below, with alternating aspect ratios. It may be preferred by North American architects because the aspect ratios (4:3 and 3:2) are ratios of small integers, unlike their ANSI (or ISO) counterparts. Furthermore, the aspect ratio 4:3 matches the traditional aspect ratio for computer displays.

The size Arch E1 has a different aspect ratio because it derives from adding 6 inches to each side of Arch D or subtracting the same amount from Arch E. Printer manufacturer recognize it as ''wide-format''.<ref name="PWG"/> An intermediate size between Arch C and D with a long side of {{convert|30|inch|mm}} does not exist.
<!-- Someone please explain the weird E2 and E3 here! PWG 5101.1 now has them -->

{| class="wikitable"
|+ US architectural standard paper sizes<ref>{{cite web |url=https://sizes.com/materials/paperUStech.htm |title=Technical drawing paper sizes in the United States |archive-url=https://web.archive.org/web/20161008145734/http://sizes.com/materials/paperUStech.htm |archive-date=8 October 2016}} at sizes.com</ref>
|-
!colspan=2| Names
! inch × inch !! mm × mm !!title="aspect ratio"| AR
|-
! Arch A !! Arch 1
| {{size|9|12|in|mm|ar=on}}
|-
! Arch B !! Arch 2
| {{size|12|18|in|mm|ar=on}}
|-
! Arch C !! Arch 3
| {{size|18|24|in|mm|ar=on}}
|-
! Arch D !! Arch 4
| {{size|24|36|in|mm|ar=on}}
|- title="wide format"|
! Arch E1 !! Arch 5
| {{size|30|42|in|mm|ar=on}}
|-
!colspan=2| Arch E2<ref name="PWG"/>
| {{size|26|38|in|mm|ar=on}}
|-
!colspan=2| Arch E3<ref name="PWG"/>
| {{size|27|39|in|mm|ar=on}}
|-
! Arch E !! Arch 6
| {{size|36|48|in|mm|ar=on}}
|}