Onslow County, NC Building Setbacks & Zoning: Setback Rules (2026)

Table 8-1 (Residential District Dimensional Standards) sets front setbacks at 30 feet in RA, 25 feet in R-20, and 20 feet in R-15, R-10, R-8M, and R-5. Side setbacks run 8 feet in RA, R-20, R-15, and R-10, dropping to 5 feet in R-8M and R-5. Rear setbacks are a flat 15 feet across every residential district. Note 1 states: "All front setbacks shall be measured from the right-of-way line or access easement," and Note 2 adds that "Corner Lots shall have a side street setback of 20 feet and the applicant shall designate the front and side yards regardless of the building's orientation or driveway location."

Non-residential districts follow a separate table, Table 8-4. HB and CB require a 30-foot front setback, O-I requires 25 feet, and L-IN, H-IN, and CON also require 30 feet. Side setbacks are 10 feet in HB, CB, O-I, and CON, rising to 30 feet in L-IN and H-IN. Rear setbacks run 25 feet in HB, CB, and O-I, and 30 feet in L-IN, H-IN, and CON.

Section 8.6(C) allows limited setback encroachments: new construction gets an 18-inch allowance for ground-mounted mechanical equipment, uncovered porches, steps, stoops, and architectural features like eaves, bay windows, and chimneys. Existing buildings can encroach further for ADA ramps and fire escapes. Section 6.4(B) also lets the Zoning Administrator relax setbacks by up to 30 percent for a nonconforming lot of record that can't otherwise meet the district's dimensional standards.