Boulder, CO Fence Regulations: Fence Permit Requirements (2026)

Section 9-9-15(b) of the Boulder Land Use Code permits a fence, hedge, or wall, defined to include retaining walls, columns, posts, and piers, only if it meets the section's location and height standards along with the sight-triangle rules of Section 9-9-7 and the building code in Chapter 10-5. No fence may cross a property line without the abutting owner's agreement, and none may sit nearer than eighteen inches to a public sidewalk (Section 9-9-15(b)(1)-(2)). Height is capped at seven feet for any fence, wall, or hedge combination within three feet of itself on the same lot, measured from finished grade to the tallest point (Section 9-9-15(c)); a fence on a retaining wall may add up to forty-two inches without counting the wall's height, fences on a shared property line can reach twelve feet with the neighbor's written agreement, athletic-facility fencing can reach ten feet if the top three feet are at least half open, and a temporary construction fence has no height cap during construction (Section 9-9-15(c)(2)).

05 for each $100 of value with no maximum under the building permit fee schedule in Section 4-20-4(f)(2), and a Class E building contractor license, which specifically covers 'all fences of any size or value,' is required of anyone contracting to build one commercially (Section 4-4-4(e)). Barbed wire or electrically charged fencing is generally prohibited, but Section 9-9-15(d) allows a temporary construction fence topped with barbed wire, an internal livestock fence in the A district, and an electric fence in the A, RR, RE, or RL districts to protect crops, provided the electric fence stays at least five feet inside the property line, sits behind a non-electric perimeter fence, and no person shall maintain an electric fence without a fence permit. 5 of Title 10 (Section 9-9-15(e)).