Boulder, CO Building Setbacks & Zoning: Setback Rules (2026)

Boulder does not set one citywide setback: Section 9-7-1, 'Schedule of Form and Bulk Standards,' states that all primary and accessory structures are subject to the dimensional standards set forth in Table 7-1 of that section, and the table assigns separate minimum front, side, and rear yard figures to each of the city's zoning district groups, labeled Form Modules a through s. In the Agricultural (A) district, the first column of Table 7-1, the minimum front yard landscaped setback is 25 feet, the minimum side yard setback from an interior lot line is 15 feet, the minimum total for both side yards combined is 40 feet, and the minimum rear yard setback is 25 feet.

Other districts carry different figures under the same table, ranging down to a zero-foot setback in some business and downtown districts where buildings are allowed to sit at the property line. Section 9-7-2, 'Setback Standards,' supplies the rules for applying those table minimums: front yards may be reduced under the setback-averaging rule in Subsection 9-7-2(b) when more than half the buildings on the same block face already sit closer to the street than the table minimum, and Subsection 9-7-2(c) sets separate maintenance-easement and wall-height rules for residential districts that allow a zero side yard.

A property owner has to check the district-specific row in Table 7-1 before any addition or new structure, since the same setback label carries a different number in nearly every zoning district.