How it stays accurate. Each storey's outline is taken from the heavy lines on its floor plan — the walls — with the door and window gaps closed, so the footprint is the architect's, not a tracing. Box just the one floor plan (leave the deck out if you don't want it). The upper floor is stood on the one below by matching its outer walls. The scale comes from the sheet's scale note, or from the house's overall width if the sheet has none. Wall heights come from you, off the elevation; the roof is generated over the outline at the pitch you set. Every model is checked by a person against the plans before it prints — we'll email you if something on the sheet needs a decision. PLA, four colors, the pieces printed separately and assembled.