Hillsboro, OR Zoning Overlays & Bonuses: Downtown Design Guide (2026)

1). New residential construction must replicate major elements of 1890s-1930s architecture. The garage front must sit back at least 5 feet from the dwelling's front building plane. Front or wrap-around porches, where provided, are encouraged to have a minimum area of 80 square feet, a minimum depth of 5 feet, a roof or balcony cover, and elevation of at least 24 inches above finished grade. Foundations must raise the finished floor 24 to 32 inches above grade; plain concrete or concrete block is allowed only if that elevation is 28 inches or less.

Horizontal siding must run a narrow course (6 inches to the weather for bevel or clapboard, 10 inches for drop or rustic siding); concrete slab, concrete block, corrugated metal, plywood or T-111, sheet pressboard, oriented strand board and aluminum siding are all barred. Windows need a 3:2 height-to-width ratio and trim at least 3 inches wide and 5/8 inch thick. Roof pitch must run at least 4/12 for hips and 6/12 for gables, with overhangs of at least 18 inches at the eaves and 1 foot at the gable ends; roofing must be slate, terra cotta, concrete tile, composition or cedar shingles, or standing-seam metal in gray, black or brown.

Entry and porch lighting is required on every new dwelling and capped at 2 lumens with no glare onto neighboring property. New multi-dwelling buildings need a roof gable, dormer or bay window on every street-facing elevation. C: matching materials, compatible colors, roll roofing allowed only with required parapets on flat roofs, tripartite street-facing façades, and exterior lighting capped at 4 lumens that cannot spill onto adjoining residential property. Mechanical equipment must be screened from street level or hidden from the right-of-way. 156(C), and converting an existing dwelling into middle housing need only avoid increasing nonconformance with these standards.