Do you need a permit for a fence or deck in California?

Section R105.2 of the 2025 California Residential Code lists work exempt from a building permit. Four items matter for fences, decks and the work around them:

Fences not over 7 feet (2134 mm) high. (item 2)

Retaining walls that are not over 4 feet (1219 mm) in height measured from the bottom of the footing to the top of the wall, unless supporting a surcharge. (item 3)

Sidewalks and driveways. (item 5)

Decks not exceeding 200 square feet (18.58 m2) in area, that are not more than 30 inches (762 mm) above grade at any point, are not attached to a dwelling or townhouse and do not serve the exit door required by Section R318.4. (item 10)

Each condition in the deck item has to be true at once. A 150-square-foot deck that is attached to the house needs a permit. So does a detached deck that is 32 inches above grade at its low corner.

The exemption covers the building permit only. The code itself adds that exemptions "shall not be deemed to grant authorization for any work to be done in any manner in violation of the provisions of this code or any other laws or ordinances of this jurisdiction."

In practice that leaves three other layers:

1. Zoning limits on height and location, which apply to every fence.
2. Planning or fence permits, which some towns require even for short fences.
3. Local amendments to the state exemption, which can be stricter.

Palo Alto, Los Altos and East Palo Alto regulate fence height and location through zoning; the city pages linked below list the limits.

Minor maintenance may be treated differently from replacement, but local rules vary. Three Peninsula towns make the distinction unusually explicit:

• Los Altos Hills: repair of less than 50 feet, or no more than 25% of the total length, of a legal nonconforming fence can go ahead without a permit. Replacing that fence means meeting current rules.
• Portola Valley: once more than 25% of the fencing in required yards is damaged or removed, the replacement portion must conform to current fence regulations.
• Woodside: repair of less than 100 feet, and no more than 50% of a fence segment within 12 months, needs no permit. An existing fence can be replaced if the new one is a like material, no taller and no closer to the property line (WMC § 153.212(B)(12)).

The practical rule elsewhere: if the work changes the height, the location, or the material, treat it as a new fence and check before starting.

For decks, height above grade decides more than size. A freestanding deck no larger than 200 square feet and no more than 30 inches above grade at every point is exempt from a building permit. A deck that is higher at any point does not qualify. An attached deck does not qualify either, regardless of height, because the exemption applies only to decks that are not attached to the dwelling or townhouse. Separately, the residential code requires guards where an open-sided walking surface is more than 30 inches above the floor or grade below at any point within 36 inches horizontally of its edge.

Certain wood-supported exterior elevated elements more than 6 feet above ground at apartment buildings with three or more dwelling units are subject to separate state inspection requirements under Health and Safety Code § 17973 (SB 721). Condominiums are covered by a separate inspection regime. Neither applies to a typical single-family deck.

A retaining wall holds back soil. Under the state code it needs a building permit if it is over 4 feet from the bottom of the footing to the top of the wall, or if it supports a surcharge such as a slope, driveway or structure above it, regardless of height. A fence built on top of a retaining wall raises a separate question: several cities measure the combined height.

A city can require an after-the-fact permit, inspection, changes, or removal of work that needed a permit and did not get one. At sale, California's Real Estate Transfer Disclosure Statement asks the seller to disclose "room additions, structural modifications, or other alterations or repairs made without necessary permits" and "features of the property shared in common with adjoining landowners, such as walls, fences, and driveways" (Civil Code § 1102.6).

Do I need a permit to replace my fence with the same fence?
Under the state code, not for a building permit if it stays at 7 feet or under. Some towns require a planning or fence permit for any fence in a setback, and Los Altos Hills, Portola Valley and Woodside set specific thresholds for when replacement must meet current rules.

Does a 7-foot fence need a permit?
Not a building permit under the state code. Mountain View requires a planning permit and written consent from adjacent neighbors for any fence over 6 feet on a single-family lot; on the building permit its own pages differ, so confirm with the Building Division.

Is a ground-level deck exempt?
A freestanding deck no more than 30 inches above grade at every point and no larger than 200 square feet is exempt from a building permit under CRC R105.2, as long as it does not serve the required exit door. Zoning setbacks can still apply.

Who applies for the permit, the homeowner or the contractor?
Either can, depending on the city. Whoever applies is responsible for the work matching the approved plans.

• How tall a fence can be, city by city
• Who pays for a shared fence
• Finding the property line
• California's balcony inspection laws
• Deck rot: repair or replace
• City fence rules

• California Residential Code (2025, with January 2026 errata), § R105.2, items 2, 3, 5, 10. codes.iccsafe.org
• Exemption preamble as adopted locally: Palo Alto Municipal Code § 16.04.110 (Ord. No. 5674, 2025).
• City of Menlo Park, Fences and walls in residential areas. menlopark.gov
• City of Mountain View, Fences or Walls (residential). developmentpermits.mountainview.gov
• City of Mountain View, Projects that Don't Require Permits. developmentpermits.mountainview.gov
• Mountain View City Code § 8.36.05 (Ord. No. 9.2025, September 9, 2025); California Building Code (2025) § 105.2, Building, item 2. library.municode.com
• Redwood City Zoning Code, Article 36, § 36.3 (version of September 24, 2026). library.municode.com
• Town of Atherton, Fences, Walls, Gates and Columns guidelines, rev. December 8, 2022. athertonca.gov
• Woodside Municipal Code § 153.212 (version of June 8, 2026). library.municode.com
• Town of Woodside, Fence/Wall/Gate/Pylon/Berm Permit Application, rev. July 8, 2025. woodsideca.gov
• Town of Los Altos Hills, Fences, Walls, Gates and Columns, October 17, 2025, § 10-1.507(g). losaltoshills.ca.gov
• Town of Portola Valley, Municipal Code § 18.43.080; Fence Permit Application, rev. July 1, 2023. portolavalley.net
• California Civil Code § 1102.6. leginfo.legislature.ca.gov

General information, not legal advice. Permit rules change; confirm with the city's building and planning departments before starting work.