Ayer, MA Permit Requirements: Fence Permits (2026)

The Massachusetts State Building Code (780 CMR) exempts fences 6 feet or less in height from building permits statewide. This applies across all 54 municipalities in Middlesex County. Fences exceeding 6 feet require a building permit with structural plans. Municipal zoning bylaws layer additional height and placement restrictions: front yard fences are typically limited to 4 feet, side and rear yard fences to 6 feet, though exact limits vary. Massachusetts' unique 'spite fence' law (MGL Chapter 49 §21) provides that a fence over 6 feet that is unnecessarily erected for the purpose of annoying the adjoining landowner is a private nuisance. This can be raised even when a fence technically complies with zoning — the malicious intent makes it actionable. Some municipalities in Middlesex County require a zoning permit for fences even when no building permit is needed — this is a simpler review process to ensure setback and height compliance. In historic districts (Cambridge, Concord, Lexington, etc.), fences visible from public ways may require Historic District Commission review for materials and design. Fences near wetlands may need Conservation Commission approval under the Wetlands Protection Act (MGL Chapter 131 §40). Pool fences must comply with Massachusetts State Building Code requirements: minimum 4 feet tall with self-closing, self-latching gates (780 CMR 3109). Property line disputes are common in older New England neighborhoods where boundaries were historically marked by stone walls — a professional survey is recommended before fence installation.