Sonoma's Fence Regulations: The Rules That Matter

Every city handles fence regulations a little differently. In Sonoma, California, there are 5 distinct rules that residents and property owners should be aware of. Some are stricter than what neighboring cities enforce, and others are more relaxed. Here is what you need to know.

Height Limits

Per SMC 19.46.030, fences in front and street-side setbacks are limited to 3.5 feet; rear and interior side yards generally allow up to 7 feet (8 feet with the top foot at least 40% open). Corner-lot sight triangles cap fences at 30 inches.

Key details: Front/street-side max: 3.5 feet (42 inches). Side/rear yard max: 7 feet (8 feet if top 1 ft is 40%+ open). Corner sight triangle max: 30 inches. Code citation: SMC 19.46.030. Modification: Use permit from Planning Commission.

Fence-height violations are enforced under SMC Chapter 19.90 (Enforcement of Development Code Provisions). The Planning Department issues notice to comply; continued violation is treated as a public nuisance and may be prosecuted as a misdemeanor or infraction under the general penalty provisions of SMC Title 1, with civil penalties and abatement costs recoverable. Property owners are typically ordered to lower or remove the noncompliant fence within a set time.

Approved Materials

Sonoma Municipal Code Ch. 19.46 regulates fence materials, including special wall and fencing guidelines (SMC 19.46.070) and material restrictions (SMC 19.46.080). Solid wood, masonry and concrete fences over 7 feet require a building permit; all fences over 10 feet do regardless of material.

Key details: Permit-free solid fence: 7 feet or less. Permit-free open fence: 10 feet or less. Above 7 ft solid: Top must be 40%+ open. Code citation: SMC 19.46.070, 19.46.080. Building permit: Required above thresholds.

Use of a prohibited or non-conforming material is enforced by the Planning and Building Departments under SMC Ch. 19.90. The City issues a notice of violation; failure to cure can result in administrative citations, civil penalties, and abatement at the owner's expense. Building a permit-required fence without a permit can also trigger investigation fees and double permit fees.

Neighbor Fence Rules

California's Good Neighbor Fence Act (Civ. Code §841) presumes adjoining owners share equally in the reasonable cost of a boundary fence and requires 30 days' written notice before incurring shared costs. Local fence height and material rules in SMC Ch. 19.46 still apply.

Key details: State statute: Cal. Civ. Code §841. Cost presumption: Equal share. Notice required: 30 days written. City mediates disputes: No - civil court. Local rules still apply: SMC Ch. 19.46.

Failure to give the required 30-day notice can be raised as a defense or basis to reduce a neighbor's cost claim. If a fence is built that violates SMC Ch. 19.46 (e.g., too tall, prohibited material, in a sight triangle), the city's Planning/Building Division will enforce regardless of the neighbors' private agreement, and the owner of the property where the fence is located is responsible for compliance.

Retaining Walls

Per SMC 19.46.040, retaining walls in Sonoma may not exceed 6 feet measured from finished grade at the base of the wall. Walls over 4 feet of unbalanced fill (measured from bottom of footing to top of wall) require a building permit under the California Building Code.

Key details: Max height: 6 feet from finished grade at base. Code citation: SMC 19.46.040. Building permit threshold: Over 4 ft (bottom of footing). Measured from: Finished grade at base (downhill). Hillside review: Geotechnical may be required.

Building a retaining wall taller than 6 feet without a use permit is a violation of SMC 19.46.040 and is enforced under SMC Ch. 19.90. Building a permit-required wall without a building permit triggers stop-work orders, investigation fees, and potential double permit fees from the Building Division. Continuing violations may result in administrative citations and abatement actions.

Pool Barriers

California's Swimming Pool Safety Act (Health & Safety Code §§115920-115929) controls pool barriers in Sonoma. Enclosures must be at least 60 inches tall with self-closing/self-latching gates opening away from the pool, and new/remodeled pools must include at least two of seven approved drowning-prevention safety features.

Key details: Minimum enclosure height: 60 inches. State law: HSC §§115920-115929. Safety features required: At least 2 of 7 (HSC §115922). Gate: Self-closing, self-latching, opens away. Max ground gap: 2 inches.

Pool barrier violations are a building code and life-safety violation enforced by the Building Division. Building a pool without compliant barriers or modifying an existing barrier to a noncompliant state can result in stop-work orders, mandatory drain-down or fencing, administrative citations, and denial of certificate of occupancy. Civil liability under HSC §115920 et seq. and tort law for drownings is substantial.

Compared to other cities, Sonoma takes a harder line on pool barriers. The enforcement and penalty structure reflects that.

The Bottom Line

Sonoma's fence regulations 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 Sonoma is broadly strict or permissive.

This guide is based on Sonoma's current municipal code. Local rules can and do change, so check the individual ordinance pages for the latest details, penalties, and FAQs.