Depending on your need, I think a phone scanner (I use Fastscanner) is a viable workaround for what I interpret your situation to be. It does not automatically save as a pdf in Arch D format, for example, but the quality from a decent original is okay when the whole sheet is in the image. (I just tried it with a 24"x36" on the floor) These programs take the phone image, adjust the contrast so that it reads like a b/w drawing, and save as a pdf or jpg.
It's not ideal if you need to be able to scale the resulting drawing, but it works if, for example, you have a drawing at your home office and you need to share it with a colleague at her/his home office. Consider putting a graphical scale on the drawing before the photo-scan.