Building Setbacks & Zoning in Hillsboro, OR

If you live in Hillsboro or are thinking about moving there, building setbacks & zoning are one of those things you probably won't think about until they affect you directly. Hillsboro has 3 specific rules on the books covering different aspects of building setbacks & zoning, and some of them might surprise you.

Lot Coverage Limits

In Hillsboro's R-10 single-family zone, buildings can cover no more than 40% of an interior lot or 45% of a corner lot; other zones set their own caps.

Key details: R-10 interior lot cap: 40% of lot area. R-10 corner lot cap: 45% of lot area. What counts: buildings over 24 inches tall. Cottage clusters: exempt from this standard. Governing section: CDC § 12.21.150, Table 12.21.150-1.

Building beyond the coverage cap requires an approved Variance or Adjustment under CDC §§ 12.80.150-12.80.156 before construction; the Planning Division can reject a building permit or issue a stop-work order for coverage that exceeds the approved plan.

Setback Rules

In Hillsboro's SR-6 zone, the most common single-family and middle-housing district, front yard setbacks on interior lots run 20 feet to the dwelling or garage door, side yards are 5 feet, and rear yards are 20 feet, per Community Development Code § 12.21.450, Table 12.21.450-1. Every setback in the city is measured and enforced under the citywide standard in CDC § 12.50.130.

Key details: SR-6 front yard (interior lot): 20 ft to dwelling or garage door. SR-6 side yard: 5 feet minimum. SR-6 rear yard: 20 feet minimum. Cottage cluster front/rear to dwelling: 10 feet. Compliance date: structures built after Sept. 4, 2014.

CDC § 12.50.130 sets no dollar fine of its own; a setback violation runs through the city's land use process rather than a criminal penalty. A structure built out of compliance with Table 12.21.450-1 must be corrected to meet the standard, or receive a Variance under CDC § 12.80.150 or a Minor or Major Adjustment, before it can be finaled. Structures that predate the September 4, 2014 setback standards and are already nonconforming may remain and be altered only if the alteration does not increase the deviation from the current standard, per CDC § 12.30.600.

Structure Height Limits

In Hillsboro's R-6 (single detached, duplex and triplex) residential zone, Table 12.21.450-1 caps building height at '2½ stories or 35 feet, whichever is less.' Height is measured under Community Development Code § 12.50.140 from finished grade at the center of the front building plane, following the illustrated methods in Figure 12.50.140-A for flat, mansard and pitched or hip roofs; the standard applies citywide within the R-6 zone, one of several residential base zones.

Key details: Governing provision: CDC Table 12.21.450-1, R-6 zone. Height cap: 2½ stories or 35 feet, whichever is less. Measurement rule: CDC § 12.50.140(B), from finished grade. Minimum height: None. Exceeding the cap: Requires Variance/Adjustment, § 12.80.150.

Construction exceeding the 35-foot or 2½-story cap in Table 12.21.450-1 without an approved Variance or Adjustment under Section 12.80.150 is a Development Code violation, enforceable through the Building Division's plan-review and permitting process; the Building Official can withhold a building permit or certificate of occupancy for a structure that does not conform to the approved height and measurement standard in Section 12.50.140.

The Bottom Line

Hillsboro's building setbacks & zoning rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Hillsboro is broadly strict or permissive.

All of the above reflects Hillsboro's municipal code as of our last review. If you need specifics on fines, exemptions, or filing requirements, the detailed ordinance pages linked above have the full breakdown.