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Home > Guides > Faxing architectural drawings
Not well. A fax machine only scans sheets about 8.5 inches wide, so a 24-by-36-inch drawing shrinks to letter size and the fine lines, dimensions, and text turn unreadable. Faxing is built for text documents, not large-format plans. If a client or building department insists on a faxed plan, scan the drawing to a PDF and send that instead.
| Drawing sheet size | What a fax does to it |
|---|---|
| C size (17 x 22 in) | Reduced to fit 8.5 in width; text and linework shrink to about half |
| D size (24 x 36 in), the common architectural sheet | Crushed down to letter width; 1/8-inch scale text becomes dots |
| E size (36 x 48 in) | Nearly 5x reduction; dimension strings and hatching merge into blobs |
| 11 x 17 in half-size sheet | Still cropped or reduced; fits length-wise only if the machine takes legal paper |
A fax treats every page as a scanned image sent over a phone line. The sending machine scans at fax resolution, compresses the image, and the receiving machine prints whatever arrives at letter or legal width. Three things go wrong with drawings.
First, the width limit. Most fax machines accept sheets up to 8.5 inches wide. A few office machines take 11-by-17-inch sheets, but nothing larger. A full-size drawing physically cannot go through most machines, so the sender has to reduce it on a copier first, and every reduction step loses legibility.
Second, resolution. Fax was designed for typed text, not linework. Fine line weights blur together, hatch patterns fill in solid, and grid lines can alias into wavy moire patterns. A dimension string like "12'-6"" can read as "12'-8"" or vanish entirely, which is a real problem on a permit set where dimensions carry legal weight.
Third, black-and-white only. Color-coded layers, revision clouds in red, and revision annotations all land as the same shade of gray. Reviewers cannot tell what changed or what was flagged.
Almost never, but there are edge cases. A rough sketch on letter-size paper faxes fine. A single detail drawn at full scale on an 8.5-by-11 sheet can go through cleanly. And if the recipient's process still runs on fax and they only need to see the general layout, a reduced copy may be enough for a preliminary chat. But anything that will be measured, permitted, or built from needs a better channel.
The standard answer in architecture and engineering is a PDF. A PDF keeps the sheet at full size, preserves every line weight and color, and the recipient can zoom and print it at whatever scale they need. Most offices now have a large-format scanner or use a copy shop for sheets they cannot scan in-house. Phone apps can capture smaller drawings well enough for discussion, but they should not replace a scanned plan for anything official.
If the recipient genuinely only accepts faxes, the least bad option is to have the drawing scanned to a PDF and faxed through an online fax service, where the PDF is converted on the way in. The output is still a fax with fax quality, but at least the conversion is consistent and you keep the clean original. LetterAgent sends faxes to US and Canadian fax numbers (fax is currently in testing, so availability is limited), and the page count is quoted up front before you approve the send.
Ready to fax it? Fax with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it is sent.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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