Open assumptions · what each one carries
Stated on the sheets · heights the author did print
Two ceiling heights are printed on A2.1, both room-scoped. They tell you the ensuite ceilings, not the plate. Nothing in either sheet states a plate height, floor structure depth or slab thickness. That is not a defect in the drawings; it is what plans are for. Sections carry the rest, and there are none in this set.
The estimate
The base is the ResonAi basis-of-estimate workbook for this set: 4,055 sq ft gross across both dwellings at a 2026 Okanagan benchmark, elemental split per NAHB, markups and escalation per the workbook. That base is $1,871,640 and it is Class D.
What moves
Drag a plate height and watch. Two elements of the split scale with wall area: exterior enclosure (A3, 13.4% of net) and interior partitions (B1, 9.0%). Wall area is measured length × height. Length is measured from the sheets. Height is whatever the register says. Change a plate height and those two elements re-scale by the ratio of new wall area to base wall area; everything else holds.
What this is not
Not a unit-rate takeoff. No rate in this page was invented; the split is the workbook's and it is provisional until replaced with a sourced rate set. The point of the moving number is the direction and the size, not the cents.
What "resting on assumptions" means
The share of the estimate whose weakest input is an assumption. A wall's volume is length × thickness × height; if the height is assumed, the volume is assumed, however exact the other two are. When the author states a height, that share moves out of amber.
Method, in brief
Sheets calibrated from grid bubbles at 18.003 pt/ft against a stated 1/4"=1'-0" (18.000), median error 0.21% over 26 dimension checks. A wall is two parallel lines 3–14 pt apart with real overlap; thicknesses resolve to 4.00, 6.00 and 8.00 inches without rounding. Collinear faces merged across gaps under 4 ft, every gap logged. Two-line pairs that resolve to no standard thickness, or under 2 ft long, are shown flat and grey, or dropped: cabinets, counters and cross-pairings that a person would sort in a minute.
