Broomfield, CO Building Setbacks & Zoning: Lot Coverage Limits (2026)

The Transitional Overlay Area District applies to rural residential neighborhoods adjacent to principal arterial streets identified in the Broomfield Comprehensive Plan, under section 17-25.1-010, and its rules under section 17-25.1-040 supersede the underlying zone district's requirements where they conflict. Section 17-25.1-050(B) caps total lot coverage for all built structures, including accessory buildings, at 20% of the total lot area, with no single building footprint exceeding 10,000 square feet, and combined building and parking coverage held to 60% of the gross land area. The same section pairs the coverage cap with a one-acre minimum lot size under subsection (C), a 20,000-square-foot maximum building size under subsection (D), a 35-foot maximum building height under subsection (E), and a building mass limit of no more than 150 feet in length or width under subsection (F).

A comparable but separate coverage rule applies in the older Neighborhood Overlay Area under section 17-25-050(A)(1): single-family lot coverage there is capped at 2,500 square feet on lots up to 7,000 square feet, or 35% of lot area on larger lots, a tighter residential-only standard distinct from the transitional overlay's 20%/60% commercial-and-residential coverage formula. Development within the transitional overlay must also provide a minimum of 40% open area under section 17-25.1-050(L)(4) and set buildings and parking back at least 40 feet from the arterial street.