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.

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.

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 single detached and middle housing zone, a house needs a 20-foot front yard, a 5-foot side yard and a 20-foot rear yard. Corner lots get 10 feet on one street frontage and 20 feet on the other, garage doors sit 20 feet back, and no maximum setback applies. Section 12.50.130 applies these minimums to any structure or part of a structure more than 24 inches above grade.

Key details: Front yard, interior lot: 20 feet to dwelling or garage door. Front yard, corner lot: 10 feet on 1 frontage, 20 feet on the other. Side yard: 5 feet. Rear yard: 20 feet. Maximum setback: None in the SR-6 zone.

A structure built after September 4, 2014 that sits inside a required yard needs approval through one of four routes listed in Section 12.21.460: a Variance under 12.80.152, a Minor Adjustment with a Type II or Type III application under 12.80.154, a Major Adjustment with a Type III application under 12.80.156, or a Significant Natural Resource Permit under 12.80.130. The setback sections read for this page print no fine, so the remedy is relocating or redesigning the structure or winning one of those approvals. An existing building with a nonconforming setback can be altered only if the change does not increase the deviation, under Section 12.30.600.

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.