Bolthole Index

Santa Clara County, California

Zoning, building permits and septic rules in Mountain View, California

Mountain View, California requires a building permit for a new single-family home or duplex, and the City sets zoning under Chapter 36 of its code12. Owners of single-family and duplex properties may elect to sign as owner-builders3. Septic permits in Santa Clara County, which includes Mountain View, are issued by the county Department of Environmental Health, not the City4.

At a glance

Building permit
Required for a new single-family home or duplex; apply online through ePermitsMV15
Zoning
City zoning under Chapter 36, with district-specific standards2
Septic
County Department of Environmental Health issues septic permits4
Owner-builder
Allowed for single-family and duplex properties3
Minimum lot (R1)
6,000 square feet for new subdivisions6
Minimum lot (R2)
7,000 square feet for new subdivisions7
Overnight camping
Not allowed on a vacant lot without the owner's permission8

Who to call

Building permits

City of Mountain View Building Division

Building permits for new single-family homes and duplexes inside Mountain View city limits

(650) 903-6313

[email protected]

500 Castro Street, Mountain View, CA 94041

Online permits →

Planning & zoning

City of Mountain View Planning Division

Zoning standards and planning review for lots inside Mountain View city limits

(650) 903-6306

[email protected]

500 Castro Street, Mountain View, CA 94041

Online permits →

Septic permits

Santa Clara County Department of Environmental Health

Septic (onsite wastewater treatment system) permits for new systems and repairs, and installation inspections, in Santa Clara County

Contact details are copied from each office’s official page and were checked against it on October 10, 2026.

Off-grid gear

Going off-grid in Mountain View means bringing your own water and power. The kit we’d start with:

These are affiliate links — we may earn a commission, at no cost to you. As an Amazon Associate, Bolthole Index earns from qualifying purchases.

Do you need a building permit in Mountain View, CA?

Yes. Mountain View requires a permit to construct a new single-family home or duplex inside city limits1. A new home also needs separate electrical, mechanical, plumbing, demolition and excavation permits, and a flood permit if the lot is in a flood zone9.

The City adopts the California Building Standards Code by reference with local amendments, and applications submitted from January 1, 2026 must comply with it10. California also states that no building may be erected, altered, moved or demolished without a permit11.

Expect real cost. The City's fee page lists building inspection at $218 per hour where no other fee is specified12, and the City's new-home page puts building permit fees for a single-family home at $15,000 to $25,0009.

Who issues building permits in Mountain View, and how do you reach them?

The City of Mountain View, not Santa Clara County, issues building permits inside city limits. Building and fire protection permits must be submitted electronically on the City's ePermitsMV portal5.

The Building Division can be reached at (650) 903-6313 or [email protected], and the Planning Division at (650) 903-6306913. Both are at City Hall, 500 Castro Street, first floor9.

Santa Clara County's own Department of Planning and Development issues building permits only for unincorporated land, so its rules do not apply to a lot inside Mountain View14.

Does Mountain View have zoning, and what does it mean for lot size and setbacks?

Yes. The City administers its own zoning under Chapter 36 of the city code, with district-specific standards2. Zoning districts, not one citywide rule, decide what you can build, so look up the exact district for a parcel first.

In the R1 single-family district, new subdivisions need lots of at least 6,000 square feet6. In the R2 one- and two-family district, the minimum is 7,000 square feet7.

R2 buildings are limited to 24 feet for one story and 30 feet for two stories15. R2 front setbacks start at a 20-foot minimum for the first-floor wall16. Detached accessory structures in R1 and R2 may not cumulatively cover more than 30 percent of the required rear yard17.

Subdividing into three or more lots where one lacks street frontage requires a planned unit development permit18.

How do septic permits work in Mountain View?

Santa Clara County's Department of Environmental Health, not the City of Mountain View, handles septic permits and issues them for new onsite wastewater systems and repairs419. The county requires a permit to construct, reconstruct or repair an individual onsite sewage disposal system, and such systems are used where public sewer is unavailable within 300 feet of the property line20.

Soils are a challenge: only 1 percent of Santa Clara County soils rate as not very limited for a conventional drain field, so expect a site evaluation and often an engineered system21. Cesspools are not authorized in the county22.

We could not confirm whether a specific Mountain View address must connect to public sewer; ask the Building Division and the county Department of Environmental Health before you buy919.

Can you live in an RV or tiny home on your lot in Mountain View?

Camping or lodging overnight in a vacant lot or building in Mountain View without the owner's or occupant's permission is prohibited8. That rule is about permission, so it does not itself answer whether you may live in an RV on your own lot. California says RVs are not intended for occupancy as a permanent dwelling unless a local ordinance allows it23.

On lots in the RMH mobile-home district, no travel trailer, camper or other recreational vehicle may be placed for occupancy or storage24. In flood hazard areas, an RV must stay less than 180 consecutive days or be fully licensed and ready for highway use25.

We could not confirm a Mountain View rule on tiny-home occupancy. Ask the Planning Division at (650) 903-630613. Accessory dwelling units are allowed in some cases, including on qualifying flag lots26, and California requires ministerial approval of ADU applications27.

Building a home in Mountain View: the steps, in order

  1. Confirm the zoning district and its standards with the Planning Division213.
  2. If the lot is new or oddly shaped, check subdivision rules18.
  3. Decide who will pull the permit. Permits must be signed by a California licensed contractor, except that an owner of a single-family or duplex property can elect to sign as an owner-builder3.
  4. Submit the permit application online through ePermitsMV5.
  5. Get the septic or sewer question settled with Santa Clara County Environmental Health19.
  6. Build to the 2025 California Building Standards Code as amended by the City, and schedule inspections10.

What stays with Santa Clara County, and what to check before you buy

Septic permits and county wells stay with county offices, and the county's unincorporated-area rules do not apply inside city limits. For instance, the county's ban on using RVs as housing on residential lots covers unincorporated Santa Clara County only28.

Wells in the Santa Clara Valley Water District service area require a permit29. We could not confirm a well-permit rule specific to land inside Mountain View.

Before buying, check flood zone status, since flood permits and RV limits depend on it25. Prices are high: the typical Santa Clara County home value is $1,624,35630.

Watch-outs

  • The City confirms the 2025 California Building Standards Code applies to applications submitted from January 1, 2026, so older plans may need updating10.
  • We could not confirm Mountain View rules on tiny-home occupancy, wells, off-grid sanitation, or agricultural building exemptions; ask the Planning Division at (650) 903-630613.

Sources

  1. New Construction (Mountain View), quoted and re-checked
  2. R2 zone development standards (Mountain View), quoted and re-checked
  3. Who Can Sign For a Permit? (Mountain View), quoted and re-checked
  4. Onsite Wastewater Treatment System (OWTS), quoted and re-checked
  5. Permit Center (Mountain View), quoted and re-checked
  6. Minimum lot area and width in R1 subdivisions (Mountain View), quoted and re-checked
  7. Minimum lot area and width in R2 subdivisions (Mountain View), quoted and re-checked
  8. Camping, etc., on property without owner's permission (Mountain View), quoted and re-checked
  9. City of Mountain View Building Division (developmentpermits.mountainview.gov)
  10. Building and Fire Codes (Mountain View), quoted and re-checked
  11. Do I need a building permit for my project? (California statewide rule), quoted and re-checked
  12. Building Permit Fees (Mountain View), quoted and re-checked
  13. City of Mountain View Planning Division (developmentpermits.mountainview.gov)
  14. Apply for a Building Permit, quoted and re-checked
  15. library.municode.com (Mountain View), quoted and re-checked
  16. R2 zone development standards (Mountain View), quoted and re-checked
  17. Development standards for detached structures in R1 and R2 zoning districts (Mountain View), quoted and re-checked
  18. Subdivisions in the R1 zone creating parcels without required frontage (Mountain View), quoted and re-checked
  19. Santa Clara County Department of Environmental Health (deh.santaclaracounty.gov)
  20. Other approvals that may be needed for construction, quoted and re-checked
  21. Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data
  22. Santa Clara County OWTS Ordinance No. NS-517.85, quoted and re-checked
  23. hcd.ca.gov (California statewide rule), quoted and re-checked
  24. Mobile home parks/subdivisions (Mountain View), quoted and re-checked
  25. Flood-resistant development; temporary placement of recreational vehicles (Mountain View), quoted and re-checked
  26. Subdivisions in the R1 zone creating parcels without required frontage (Mountain View), quoted and re-checked
  27. Accessory Dwelling Unit Handbook March 2026 (California statewide rule), quoted and re-checked
  28. plandev.santaclaracounty.gov, quoted and re-checked
  29. Well Permits and Inspections, quoted and re-checked
  30. Typical home value (Zillow): Bolthole Index county data

Written October 10, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

Answers from the rulebook for Mountain View

Mountain View’s own rules

  • Building permitRequired

    New single-family homes and duplexes inside Mountain View city limits.

    • Permit must be obtained before construction begins.
    “Permits are required to construct a new single-family home or duplex.”
  • Owner-builder exemptionAvailable (with conditions)

    Permits for single-family home and duplex properties inside Mountain View city limits.

    • The exception is limited to permits related to single-family home and duplex properties.
    • Other building permits must be signed by a California Licensed Contractor.
    “All building permits must be signed by a California Licensed Contractor, except for permits related to single-family home and duplex properties whereby an owner can elect to sign as an owner-builder.”
  • Building code adoptedAdopted

    Building and fire permit applications inside Mountain View city limits.

    • The City adopts the California Building Standards Code by reference with local amendments.
    • The cited page states the 2026 application date.
    “Effective January 1, 2026, all applications submitted for Building and Fire permits will be required to comply with the following California Building Standards Code (State Code or Title 24) and certified standards, which are adopted by reference with local amendments by the City of Mountain View.”
  • Local zoningPresent

    Land inside Mountain View city limits; the City administers Chapter 36, Zoning.

    • District-specific standards apply.
    “The following table entitled "R2 Zone Development Standards" defines minimum standards for development within the R2 zoning district.”
  • Zoning districtsPartial

    Mountain View zoning districts, including the R1 and R2 residential districts documented in the opened code sections.

    • The provided code excerpts are a search-ranked subset of the full code and do not establish that every district or the complete zoning map was reviewed.
    “The following table entitled "R2 Zone Development Standards" defines minimum standards for development within the R2 zoning district.”
  • Minimum lot sizeSpecified

    New subdivisions in the R1 single-family residential zoning district inside Mountain View city limits.

    • R1-7, R1-8, R1-10, and R1-10+ suffixes impose different or potentially larger requirements.
    • The rule has exceptions for special limitations, planned unit developments, and urban lot splits.

    minimum lot area: >= 6000 square feet (R1 suffix districts may require more) · minimum lot width: >= 60 feet (Corner lots require 70 feet)

    “R1 | 6,000 square feet | 60 feet (corner lots: 70 feet)”
    One more reviewed finding on this topic
    • Specified — New subdivisions and duplex/two-dwelling development in the R2 one- and two-family residential zoning district inside Mountain View city limits.
      “R2 | 7,000 square feet | 60 foot corner lots: 70 feet”
  • SetbacksSpecified

    New construction in the R2 zone inside Mountain View city limits.

    • The cited front setback applies to the first-floor wall.
    • A second-floor-over-garage exception is stated.
    • Other side, street-side, rear, and interior separation standards also apply.

    front setback: >= 20 feet (5 feet from first-floor wall for a second floor over an attached garage where the garage projects forward)

    “Front 20 ft. minimum for the first floor wall; 5 ft. from the first floor wall for a second floor over an attached garage, where garage projects forward.”
  • Lot coverageSpecified

    Detached accessory structures in R1 and R2 zoning districts inside Mountain View city limits.

    • Accessory structures less than five feet in height are excluded from the cited coverage calculation.
    • Roof eaves greater than one foot count toward lot coverage.

    maximum cumulative accessory-structure coverage: <= 30 percent of required rear yard (Structures less than five feet high do not count)

    “Maximum lot coverage: All accessory structure(s) shall not cumulatively cover more than thirty (30) percent of the required rear yard, excluding accessory structures less than five (5) feet in height which shall not count toward lot coverage.”
  • Building heightSpecified

    Principal structures in the R2 zoning district inside Mountain View city limits.

    • The cited values distinguish one-story and two-story structures.
    • The code references exceptions to height limits.

    maximum height, one story: <= 24 feet · maximum height, two stories: <= 30 feet

    “Maximum building height for 1 story: 24 ft. Maximum building height for 2 stories: 30 ft.”
  • Living in an RVLimited

    Recreational vehicles placed in flood hazard areas inside Mountain View city limits.

    • The RV must be placed for less than 180 consecutive days or be fully licensed and ready for highway use.
    • Ready for highway use requires wheels or a jacking system, quick-disconnect utilities and security devices, and no permanently attached additions.

    maximum placement duration: < 180 consecutive days (Unless fully licensed and ready for highway use)

    “Recreational vehicles in flood hazard areas, shall be placed on a site for less than one hundred eighty (180) consecutive days or shall be fully licensed and ready for highway use.”
  • Camping on your landProhibited

    Camping, lodging, or tarrying overnight in a vacant lot, place where hay or straw is stored, or building inside Mountain View city limits without owner or occupant permission.

    • The rule does not prohibit the conduct when the owner or occupant first gives permission.
    “No person shall camp, lodge or tarry overnight in any vacant lot or in any place where hay or straw is stored, or in any building within the city unless the permission of the owner or occupant of the premises first be obtained.”
  • Manufactured homesLimited

    Manufactured/mobile homes and RVs on mobile-home lots or in mobile-home parks in the RMH zoning district.

    • No more than one occupied mobile home is allowed on one lot.
    • Travel trailers, campers, and other recreational vehicles may not be placed on a mobile-home lot for occupancy or storage.
    • RV spaces in RMH parks require conditional-use-permit authorization.
    “No more than one (1) occupied mobile home shall be allowed on any one (1) lot. No travel trailer, camper or other recreational vehicle shall be placed on any mobile home lot, either for occupancy or storage.”
  • Accessory dwellingsAllowed (with conditions)

    Flag lots or other lots without required public-street frontage created through qualifying R1 subdivisions inside Mountain View city limits.

    • The lot may contain one single-family dwelling, one ADU, and one JADU.
    • Other ADU standards and permit requirements may apply.
    “A flag lot or other lot without the required frontage on a public street may contain one (1) single-family dwelling, one (1) accessory dwelling unit and one (1) junior accessory dwelling unit.”
  • Subdividing landRegulated (with conditions)

    Subdivisions and qualifying urban lot splits inside Mountain View city limits.

    • R1 subdivisions creating three or more lots, including lots without public-street frontage, require a planned unit development permit.
    • Urban lot splits have separate minimum-lot and frontage standards.
    “The approval of a subdivision in compliance with Chapter 28 of the City Code (Subdivisions) that results in three (3) or more lots, where at least one (1) lot does not have the required frontage on a public street, shall require approval of a planned unit development permit to evaluate the appropriateness of the lots, establish setbacks, and address any lot design problems.”
  • Permit feesPublished

    Building, inspection, occupancy, and related permit activities inside Mountain View city limits.

    • Fees vary by permit type and task.
    • The cited schedule includes inspection and temporary certificate-of-occupancy fees.

    building inspection: 218 USD per hour (Where no other fee is specified) · temporary certificate of occupancy, single-family residential/ADU/commercial tenant improvement: 757 USD · temporary certificate of occupancy, all other development: 1725 USD

    “Building Inspection per hour or for which no fee is specified | $218 per hour”
  • Permit processPublished

    Building and fire permits inside Mountain View city limits.

    • Applications are submitted electronically through ePermitsMV.
    • In-person assistance and virtual public-counter appointments are available.
    “All Building and Fire Protection permits must be submitted electronically online at ePermitsMV.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Mountain View or Santa Clara County directly.

  • Certificate of occupancy — New or changed occupancies inside Mountain View city limits.
  • Minimum dwelling size — Residential dwellings inside Mountain View city limits.
  • Tiny homes — Tiny-home occupancy inside Mountain View city limits.
  • Off-grid sanitation — Off-grid sanitation systems on land inside Mountain View city limits.
  • Well permit — Domestic or other wells serving land inside Mountain View city limits.
3 more unanswered
  • Mandatory utility hookup
  • Agricultural exemption
  • Driveway access

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.

Unanswered questions are usually a sign that Mountain View publishes no rule on the point, not that none exists. Santa Clara County’s page lists the county offices to call.

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