Trim bids die by a thousand small omissions: the closet nobody measured, the fourth door casing, the crown in the hallway. A house scan turns trim into arithmetic.
Baseboard: perimeter minus openings
Every room's perimeter is in the scan. Subtract the doorway widths — each one measured — and you have linear feet of base per room, before you've found your tape. Chopped-up rooms with lots of corners? The perimeter already reflects them, and the corner count warns you about miter time.
Casing: a count times a formula
Doors and windows are objects in the model, each with dimensions. Casing is (2 × height + width) plus margin, per opening, summed. The scan's contribution isn't the formula — it's the census. Every opening is in the model, including the two you'd have missed walking with a notepad.
Crown: ceiling perimeter, with eyes open
For flat ceilings, crown tracks the same perimeter as base. The scan's wall heights also flag the rooms that need scaffolding instead of a stepladder — a labor line, not a material one, and the kind that erases margin when it's a surprise.
The whole-house roll-up
Per-room numbers price the rooms; the house totals price the package. Base, case, and crown linear footage across the whole home, ready for the lumber order with your chosen waste factor. And because the takeoff traces to a model, "why is the trim line this big?" has a visual answer.
The pattern holds across trades: paint is areas, flooring is areas plus perimeters, trim is perimeters plus counts. One scan, all three.