Architectural paper sizes: ARCH A to E and ANSI, and what fits at each scale

ARCH paper sizes chart

The ARCH series is the US architectural standard. Each size is half the next one up: fold an ARCH E sheet in half and you get ARCH D, fold that and you get ARCH C. E1, E2, and E3 sit outside that halving chain.

ARCH A, C, and E have a 3:4 shape. ARCH B and D have a 2:3 shape. An 11 x 17 sheet is closer to 2:3.1, so a 24 x 36 sheet scales cleanly to 12 x 18 but not to 11 x 17.

What are the ANSI paper sizes?

ANSI sizes, set by ASME Y14.1, start from US letter and double each step. Engineering offices and some civil firms plot on them. ANSI D is 22 x 34 inches, two inches smaller each way than ARCH D, and both get called "D size." Always give the inch dimensions when you order prints.

Where do ISO A sizes fit in?

ISO 216 sizes are used on projects designed outside the US and by some international firms working here. Every A size has the same proportion, so halving A1 gives A2 with no change in shape. None of them match an ARCH size exactly.

An A1 drawing plotted onto ARCH D paper at 100% leaves blank margins and fits. An ARCH D drawing plotted onto A1 at 100% gets clipped, so the plotter usually shrinks it, and the drawing stops being at scale.

Which sheet size do permit and construction sets use?

Most US permit and construction sets are drawn on 24 x 36 (ARCH D) or 30 x 42 (ARCH E1) sheets. ARCH D is the default for small and mid-size buildings. Larger commercial, healthcare, and institutional projects often move to 30 x 42 so a floor plate fits at a readable scale. ARCH E at 36 x 48 shows up on site plans and very large footprints.

The building department has the final word. Many jurisdictions state a minimum or maximum sheet size in their submittal checklist, and electronic plan review portals usually expect the PDF page size to match a real sheet. Pick one size for the whole set. Mixing 24 x 36 architectural sheets with 22 x 34 civil sheets makes the half-size set inconsistent and confuses anyone scaling a print.

What happens to the scale on a half-size print?

A true half-size print cuts every dimension by 50%, so the scale halves too. A 1/4 inch = 1'-0" plan on a 24 x 36 sheet becomes 1/8 inch = 1'-0" on 12 x 18 paper. The scale field in the title block still says 1/4 inch, so mark the set "half size" or rely on the graphic scale bar.

The common office shortcut is printing a 24 x 36 sheet on 11 x 17 paper. That is not half size. The printer fits the 24 inch side into 11 inches, a reduction of 11 / 24, or about 46%. A 1/4 inch scale becomes about 0.115 inch per foot, which matches nothing on an architect's scale.

How to measure with the right edge of the scale, and how to read a reduced print, is covered in how to read an architect's scale.

How big a floor plan fits on each sheet at 1/8 and 1/4 inch scale?

Start with the paper, then take away what is not drawing area. The numbers below assume a 1 inch binding margin on the left, 1/2 inch margins on the other three sides, and a 3.5 inch title block strip along the right edge. Firm templates vary, so treat the results as a planning estimate.

1. ARCH D width: 36 inches, minus 1 inch binding, minus 1/2 inch right margin, minus 3.5 inch title block, leaves 31 inches.
2. ARCH D height: 24 inches, minus 1/2 inch top and bottom, leaves 23 inches. The usable drawing area is about 31 x 23 inches.
3. Leave about 1.5 inches on each side for dimension strings, grid bubbles, and the drawing title. The building outline itself gets about 28 x 20 inches.
4. At 1/8 inch = 1'-0", one inch of paper is 8 feet. 28 x 8 = 224 feet and 20 x 8 = 160 feet.
5. At 1/4 inch = 1'-0", one inch of paper is 4 feet. 28 x 4 = 112 feet and 20 x 4 = 80 feet.

The same arithmetic for the three common large sheets, with sizes in inches for the sheet and feet for the floor plate:

A 200 x 150 foot floor plate fits on ARCH D at 1/8 inch scale, but not at 1/4 inch. At 1/4 inch it needs four sheets with match lines, or an ARCH E sheet at 3/16 inch. When a plan gets split, the key plan in the title block shows which part of the building each sheet covers, and the match lines have to agree across sheets.

How do you check sheet size and scale in a PDF set?

In a PDF, the page size in the document properties tells you the sheet the file was set up for. A 24 x 36 page that measures 11 x 17 was printed to PDF at the wrong size, and anything measured on it with a calibrated tool will be off by the same factor.

• Confirm every sheet in the set has the same page size.
• Calibrate the measurement tool against a known dimension string, not the title block scale.
• Check that the graphic scale bar measures true at the calibrated scale.
• Treat any sheet marked NTS (not to scale) as unmeasurable.

Which scale belongs on which drawing type is in the construction drawing scale guide. Written dimensions govern over scaled ones, so the habit to build is in how to check dimensions. For where sheet setup fits in a full review, start with how to review construction drawings and drawing types explained.

How does Helonic handle sheet size and scale?

Helonic reads each PDF sheet's stated scale, view titles, and dimension strings, and checks that dimensions agree with each other and with the drawn geometry. The dimensional verification checks flag dimension strings that do not add up and scale fields that disagree with the views on the sheet, with the sheet number for each finding.

Architectural Paper Size FAQs