Westminster, CO Building Setbacks & Zoning: Lot Coverage Limits (2026)
Key Facts
- Residential zones (RE-T1) cap
- 30% of lot area
- O1 district cap
- 5% of lot area
- B1/C1/C2/M1 districts
- No numeric cap listed
- Accessory building limit
- 5% of lot or 600 sq ft
- Combined accessory ceiling
- 2,000 sq ft per lot
Summary
Westminster caps the principal building's footprint at 30 percent of total lot area in every residential zoning district, from RE through T1. In the O1 (Open) district, the ceiling drops sharply to just 5 percent, reflecting that district's intended low-density, open-space character.
DENSITY SCHEDULE RE R1 RA R2 R3 R4 R5 T1 B1 C1&C2 M1 O1 Maximum Lot Coverage; Percent of Total Area — Principal Building: 30% 30% 30% 30% 30% 30% (d) 30% (a) (a) (a) 5%
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 12).
Full Breakdown
Section 11-4-5's Density Schedule sets Maximum Lot Coverage as a percentage of total lot area occupied by a principal building. Across the RE, R1, RA, R2, R3, R4, and T1 residential zoning districts, that ceiling is a uniform 30 percent, meaning a homeowner cannot cover more than three-tenths of the lot with the main structure regardless of which of those seven districts the property sits in. 1 dwelling units per acre. Section 11-4-5(A) makes clear these coverage figures apply to all zoning districts except Planned Unit Development, where coverage instead follows the density and dimensional requirements set out in an approved Preliminary Development Plan or Official Development Plan under Section 11-4-7(D).
Accessory buildings are governed separately: Section 11-4-6(N)(4) caps detached garages and accessory structures at 5 percent of the lot or 600 square feet, whichever is greater, with a hard ceiling of 2,000 square feet combined per lot, on top of whatever coverage the principal building already uses.
Violations & Fines
Exceeding the 30 percent (or 5 percent in O1) maximum lot coverage for a principal building is a zoning violation that can block building permit approval or a certificate of occupancy. Building officials check total footprint, including the principal structure and any accessory buildings under Section 11-4-6(N), against the applicable Density Schedule percentage before sign-off.
Frequently Asked Questions
What percentage of my lot can my house cover in Westminster?
Why is Westminster's O1 district lot coverage limit so much lower?
Do accessory buildings count toward my Westminster lot coverage limit?
Sources & Official References
Other rules in Westminster
Compare Westminster to another location·View the Colorado building setbacks & zoning overview
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