What Is a Change Order?

A change order is a signed document that modifies your construction contract: what's changing, what it costs (or credits), and what it does to the schedule — agreed before the work happens. It's the mechanism that keeps a fixed-price contract meaningful when reality intervenes. And reality always intervenes.

The three species:

1. Owner-requested. You want the window bigger, the tile upgraded, a door moved. Totally legitimate — priced, signed, built. (Just remember Module 9.2: the later the change, the pricier.)
2. Discovered conditions. The wall opens and reveals rot; the trench finds rock; the "sound" garage slab isn't (Module 6's whole warning). This is what your contingency exists for (lesson 6.9) — the change order is how contingency gets spent consciously.
3. City-driven. An inspector requires something the plans didn't show, or a plan revision ripples into built work. Rarer on well-coordinated sets (Module 9.7, still paying dividends).

The process that protects both parties: written description → fixed price or documented T&M terms → schedule impact stated → both signatures → then work proceeds. Modern builders do this by email/app in a day; it does not need to slow anything.

The failure mode to refuse: "Don't worry, we'll settle up at the end." Verbal changes accumulate into a month-eight invoice that reconstructs history in the contractor's favor — the #1 source of construction disputes, and it's fully preventable by a sentence in your contract: no extra work without a signed change order. A contractor who resists that sentence during bidding just showed you their month eight (lesson 11.6 noted this flag).

Reading change-order health: a normal ADU project sees a handful — say 3–8 — mostly small. Zero can mean a great contract or a brewing settle-up. A parade of them usually means the bid was engineered low (fantasy allowances, lesson 11.8) or the plans were thin (Module 9.1). The pattern is diagnostic; ask about it in references (lesson 11.4's question 5, closing its loop).