Zoning, building permits and septic rules in Piedmont, California

Piedmont’s own rules

• Local zoningPresent

  Land inside Piedmont city limits; the city's own zoning ordinance (Piedmont City Code Chapter 17) governs uses and development standards there.

  • Piedmont's zoning ordinance is Chapter 17 of the city code; the city's own zoning page calls it the zoning ordinance.
  • Zoning map and zone assignment are governed by City Code section 17.08.010 and the zoning map; the city Planning Division verifies a parcel's district.

  “includes both the general plan and city code chapter 17, the city's zoning ordinance.”

• Zoning districtsPublished

  Land inside Piedmont city limits

  • Five zones: Zone A single-family residential; Zone B public facilities; Zone C multi-family residential; Zone D commercial and mixed-use; Zone E single-family estate residential (City Code section 17.08.010).
  • Zone D and the other zones are subject to conditional use permit rules that the city has been amending (October 2025 ordinance 783 n.s.).

  “piedmont is divided into five districts or zones.”

• Minimum lot sizeSpecified

  Zone A (single-family residential), inside Piedmont city limits

  • Minimum lot area is subject to an exception for accessory dwelling unit construction under division 17.38 or for an SB 9 lot split under division 17.54.
  • Section 17.38 states no minimum lot area or lot size applies to approval of permits for an accessory dwelling unit.

  lot area: >= 8000 square feet (ADU construction (division 17.38) or SB 9 lot split (division 17.54))

  “zone a requirements lot area minimum 8,000 square feet, subject to exception for accessory dwelling unit construction set forth in division 17.38 or for a lot split under sb 9 set forth in division 17.54.”

  One more reviewed finding on this topic

  • Specified — Zone E (single-family estate residential), inside Piedmont city limits

    “minimum 20,000 square feet, subject to exception for accessory dwelling unit construction set forth in division 17.38 or for a lot split under sb 9 set forth in division 17.54”

• SetbacksSpecified

  Zone A (single-family residential), inside Piedmont city limits

  • Street yard setback is subject to an ADU construction exception under division 17.38.
  • Structures supporting pedestrian and vehicular access (retaining walls, driveway bridges) up to 8 feet tall may be allowed in the street yard setback.
  • Side and rear yards: minimum 5 feet, but 20 feet where the yard is street facing; section 17.20.040 contains a further 4-foot exception that was not fully extracted.

  street yard setback: >= 20 feet (ADU construction (division 17.38)) · side and rear yard setback: >= 5 feet (20 feet where the yard is street facing; 4-foot exception in section 17.20.040)

  “street yard setback minimum 20 feet for primary or accessory structure, subject to exception for accessory dwelling unit construction set forth in division 17.38.”

  One more reviewed finding on this topic

  • Specified — Zone E (single-family estate residential), inside Piedmont city limits

    “minimum 20 feet for primary and accessory structure, subject to exception for accessory dwelling unit construction set forth in division 17.38.”

• Lot coverageSpecified

  Zone A (single-family residential), inside Piedmont city limits

  • Subject to ADU construction exception under division 17.38.
  • Under section 17.38, an ADU of 800 square feet or less has no maximum lot coverage.

  lot coverage, primary and accessory structures: <= 40 percent (ADU construction (division 17.38))

  “maximum 40% lot coverage for primary and accessory structures, subject to exception for accessory dwelling unit construction set forth in division 17.38.”

  One more reviewed finding on this topic

  • Specified — Zone E (single-family estate residential), inside Piedmont city limits

    “maximum 40% lot coverage for primary and accessory structures.”

• Building heightSpecified

  Zone A (single-family residential), inside Piedmont city limits

  • Accessory dwelling units are subject to the height restrictions in division 17.38.

  structure height: <= 35 feet (accessory dwelling units (division 17.38))

  “structure height maximum 35 feet, except accessory dwelling units shall be subject to restrictions set forth in division 17.38.”

  One more reviewed finding on this topic

  • Specified — Zone E (single-family estate residential), inside Piedmont city limits

    “maximum 35 feet, except accessory dwelling units shall be subject to restrictions set forth in division 17.38.”

• Manufactured homesLimited

  Manufactured and mobile homes in Zone A (single-family residential), inside Piedmont city limits

  • Permitted use only when on a permanent foundation.

  “f. manufactured and mobile homes on a permanent foundation.”

  One more reviewed finding on this topic

  • Limited — Manufactured and mobile homes in Zone E (single-family estate residential), inside Piedmont city limits

    “e. manufactured and mobile homes on a permanent foundation.”

• Accessory dwellingsLimited

  Accessory dwelling units in Zone A (single-family residential), inside Piedmont city limits

  • Permitted as an accessory use subject to City Code division 17.38 (ADU rules).
  • An ADU or JADU is not permitted on a lot created under Government Code sections 65852.28 and 66499.41.

  “an adu or jadu shall not be permitted on a lot created pursuant to government code sections 65852.28 and 66499.41, as they may be amended from time to time.”

  One more reviewed finding on this topic

  • Limited — Accessory dwelling units in Zone E (single-family estate residential), inside Piedmont city limits

    “c. accessory dwelling unit, subject to division 17.38.”

• Short-term rentalsLimited

  Short-term rentals (under 30 consecutive days) inside Piedmont city limits

  • Requires a short-term rental permit from the city (City Code 17.40.030); permit issued by the director, valid until December 31 and renewed annually.
  • Must be in a single-family dwelling that is the owner's or a long-term tenant's primary residence; not allowed in an ADU, multi-family unit or unit under division 17.54.
  • Minimum two consecutive nights; no more than 60 days rented per calendar year; no events; $1,000,000 general liability insurance required.
  • Smoke and CO detectors, fire extinguisher and egress determined by the chief building official; inspection fee or signed safety declaration.
  • Business license tax under City Code chapter 10 applies (17.40.040).

  maximum rental days: <= 60 days per calendar year · minimum stay: >= 2 consecutive nights · liability insurance: >= 1000000 USD

  “the short-term rental must be located in a single-family dwelling unit that is the primary residence of the property owner or long-term tenant.”

• Permit processPartial

  Sewer connection permits for property inside Piedmont city limits (only the sewer-permit step is documented; building permit process not found)

  • Applications are handled by the Department of Public Works, 120 Vista Avenue, Piedmont, CA 94611, and emailed to the sewers office.
  • The form includes plan check and building official sign-off lines and a contractor and owner section.
  • The form itself states the upper lateral from the house to the sewer is the owner's responsibility (from the form text; this was not verified in the excerpt).

  “in piedmont, the property owner is responsible for the upper sewer lateral from the house outlet to and including the connection to the main.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Piedmont or Alameda County directly.

• Building permit — Building permits for new residential construction inside Piedmont city limits
• Owner-builder exemption — Owner-builder permit exemption inside Piedmont city limits
• Building code adopted — Building code adoption inside Piedmont city limits
• Inspections — Building inspections inside Piedmont city limits
• Certificate of occupancy — Certificate of occupancy inside Piedmont city limits

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.