The elevation and the portrait

An architect's elevation and a house portrait can both hang in the same hallway and both show the same front door, and they are still different species. One is a measurement with a drawing attached; the other is a likeness that happens to be measurable. Confusing them is easy, and the confusion is worth untangling because each does something the other cannot.

What the elevation is for

The elevation is a working document. It is drawn flat, square-on to the facade, with the projection removed so that every inch of paper means the same number of inches of wall. Its job is to be read with a scale rule: the mason takes heights off it, the framer takes widths, and the inspector takes both. Everything in it is subordinated to being measurable, and the price of that honesty is flatness. An elevation cannot show depth without breaking its own contract.

What the portrait is for

The portrait works the opposite way. It is drawn from a three-quarter angle so the house turns in space; it uses shade the way a face uses shadow; it drops the utilities and keeps the lilac. Its measurements are all wrong, on purpose: the corner is foreshortened, the far wall shrinks, the tree is bigger than the surveyor would allow. The portrait's contract is not with the ruler but with the memory. It is asked to look like the house as the house is known, not as the house is built.

Where the two trades meet

The interesting part is that the same hand can hold both. The architectural illustrator was trained to make elevations before she was ever asked to make portraits, and the disciplines leak into each other usefully. The portrait borrows the elevation's accuracy in the parts that matter: windows are counted, not guessed; brick courses run true; the porch steps are the right number. The elevation, for its part, borrows the portrait's presentation when it needs to be sold: presentation drawings shade, cast shadows and show the building landscaped, because a committee approves what it can imagine.

The working line between them

The cleanest way to keep the two trades straight is to ask what each sheet does with a mistake. On an elevation a wrong line is a defect; the drawing exists to be measured, so an error is a fact misplaced. On a portrait a wrong line is a decision; if the tree is a hand taller than the survey says, the sheet is still true, because its measure was the memory and not the tape. One drawing is audited against the building; the other is audited against the house as it is loved. Same wall, two different courts of appeal.

Which sheet to ask for

A client who wants a drawing to build from wants the elevation; a client who wants a drawing to keep wants the portrait. The confusion only costs when one is bought as the other. The measured drawing of a beloved house is a cold object; the likeness of a house being planned is a beautiful mistake nobody can frame.

The sheet, filed

Both drawings are true; they are true in different currencies. The elevation tells the mason where the window goes, the portrait tells the family where the window was, and the mature illustrator respects the border between them even while her pen crosses it daily. The next sheet stays on the portrait's side and opens the box where its shadows live: shade, built stroke by stroke in cross-hatching.