Do I need a permit for basement finishing in Centennial?

Most likely yes. Basement finishing usually requires a permit in Colorado. Confirm the specifics with Centennial.

Colorado has no statewide building code. Building codes are adopted and enforced by each city or county, and some jurisdictions have adopted none; where that happens the state adopts codes only for hotels, motels, and multifamily buildings, not single-family homes. Egress window and alarm rules for new bedrooms come from the residential code your jurisdiction adopted. Electrical and plumbing work need their own permits. The state Electrical and Plumbing Boards (DORA) issue permits and inspect where a city or county has no electrical or plumbing inspection program; where it does, the local office issues them. Colorado law requires any city or county that adopts or updates a building code after July 1, 2026 to adopt the state Model Low Energy and Carbon Code or a stricter one, which governs insulation of newly finished space. This basement project adds a bedroom, a bathroom or wet bar, or new electrical circuits, or moves the furnace or water heater. Finishing work of this kind normally needs a building permit and the matching trade permits. A basement bedroom needs an emergency escape and rescue opening, such as an egress window or door, which is one of the most common reasons basement work fails inspection. Plan for framing, electrical and plumbing rough-in inspections before insulation and drywall go up.