Your explanation that SU doesn’t do this is instructive. Not to be snarky but I take it you’re under 35 or 40. ;p
Drawing on paper with all its perceived limitations (and paper size isn’t really a factor) is a first fundamental in all drafting - one too many architects of today have long forgotten. For example in navigation (in the car), using only small-screen GPS denies you the bigger picture - you see only a 3-by-5-inch screen and not the larger general direction - ‘basically which way should I go and which major road tends that way?’ You become a slave to the little box which as if by design limits your vision of greater (physically bigger) reality.
In modern residential architecture it is common to see houses drawn with no overall sense of unity or scale. Residential designers develop the design from individual room sizes. When they’re all put together they consult the overall dimensions. ‘That house will be… 49’7” x 88’3”; so you need a lot at least 91 ft wide.’ That’s not really helpful if you’re a serious professional.
I cut my teeth designing for LBI and OBX where you are (were) constrained by section size and cost - draw a fast- and easy-to-build 24 x 36 Cape Cod for a 50 x 100 lot and include 4 bedrooms, garage and patio without exceeding 2500 sq ft of developed foundation on the lot and coming in within 10% of budget. It starts with an overall scale, not a two-story foyer that turns out to be 17 x 19’6” that looks really cool in 3D on estate-agents’ web listings but isn’t necessary or helpful to the project.
To the other extreme I’m currently designing a castle/palace residence over 650 ft wide for another project but, again, I know all the dimensions and just need to develop working plans. (And, no, having done this since the ‘80s I know that paper size isn’t the problem - just get more paper.)
So having and knowing the starting scale is more vital than nonprofessional residential designers might wish to believe. It’s even more vital if you’re starting a remodel with an existing structure whose dimensions are finite and nonnegotiable. What I’m asking is how I begin with plotting those dimensions.
I tend to first-plot drawing on graph paper, which is what Lloyd Wright did, because it helps constrain you to 2x4 and 4x8 material dimensions. This nets the cheapest possible way to build something amazing. (But then I grew up in a Wright-inspired tract so maybe that’s why.) I’m the architect so I’ll provide the amazing part. Having drawn like this I already know all the dimensions in scale. I want to draw them in something like SU now for the output opportunities and to print large-format working plans.
Is there a way to impose a fixed-scale graph on a SU document from the start? I’m sorry but I haven’t found that yet.