Do I need a survey to build a fence or ADU?

Sun, 08 Feb 2026 01:32:22 GMT

Many Ventura Homeowners Ask If A Formal Survey Is Required

Building a fence or an Accessory Dwelling Unit (ADU) in Ventura County often requires a land survey, though the specific triggers depend on whether you are in an incorporated city (like Ventura or Oxnard) or an unincorporated area of the county. At Land Survey Ventura, we can help you figure it all out.

1. Building a Fence or Wall

In many parts of Ventura County, a survey is not strictly required unless you are building on or very close to the property line. However, it is highly recommended to avoid "civil litigation" with neighbors.

City of Ventura: If you are building a fence or wall within 5 feet of the property line , the city requires the wet signatures of your neighbors on your site plan to verify they agree with the location. If you cannot get their signatures , you must provide a signed and stamped property survey from a licensed surveyor.
Property Line Construction: In most jurisdictions, including the City of Ventura, you cannot build a new wall directly on a property line without a recorded easement.
Simi Valley & Others: A building permit is typically not required for fences under 6 or 7 feet, but a "Zoning Clearance" is. To get this, you must submit a plot plan. While a survey isn't always mandatory for the permit, the city notes that a survey is the only "accurate way" to determine the line, and the owner bears all liability if the fence is misplaced.

2. Building an ADU

For an ADU, the requirement for a survey is much more common because of setback regulations .

Setback Verification: State and local laws usually require a minimum 4-foot setback from side and rear property lines for detached ADUs. If your proposed building is close to these limits, the Building and Safety department will likely require a survey to prove the structure isn't encroaching on the setback or the neighbor's land.

Topographic Surveys: If your property is on a slope (common in Ojai, Ventura hillsides, or Santa Paula), you will almost certainly need a topographic survey . This is required for the "Grading Permit" to show how water will drain around the new ADU.
Impervious Surface Limits: A survey is often required to calculate "pervious vs. impervious" surface area. Ventura County has limits on how much of a lot can be covered by concrete or buildings; a survey provides the exact measurements needed for these calculations.

Common "Triggers" That Make a Survey Mandatory:

Missing Property Markers: If the original iron pipes or "monuments" at your lot corners are missing or buried.
Odd-Shaped Lots: If your property is a "flag lot," is irregularly shaped, or sits on a curved street.
Hillside Areas: Any construction in designated "Hillside Overlay" zones usually requires land development approval based on a professional survey.
Encroachment Issues: If there is an existing fence that doesn't seem to align with your deed, the county will require a survey before they allow a permanent ADU foundation to be poured nearby.

Pro-Tip for Ventura County Homeowners:

Before hiring a surveyor, check VCView (the County’s GIS map). It can give you a rough idea of your property lines, flood zones, and any protected tree overlays (like the Ojai Oak tree protections) that might affect your project's footprint. For a consultation or questions, call us !

Custom Home Plans for 2021

Sun, 27 Dec 2020 13:28:16 GMT

Custom Home Plans

Custom Homes in 2021 Will Reflect the “Safer at Home” Experience of 2020

Custom Home Builders and Buyers Are Looking For Calm and Zen Spaces Where They Can Gather Family and Enjoy Being At Home.

Most custom homes today are built for families who want to create their dream home. Custom home families want a floor plan that fits their needs and that includes their extensive list of desired amenities. All this customization of plans translate into a myriad of extra costs and careful coordination of the build.

The COVID-19 pandemic has fostered a new appreciation the home and “being home.” So, custom home buyers want the space and amenities to enhance the lifestyle of the family. Safer at Home also means that mom and/or dad will be working from home for the foreseeable future. So open, bright, organized home offices are trending. We are seeing larger living space, kitchens (which are getting used more now), and a return to the pleasure of the back yard -- requiring landscaping, hardscaping, and, of course, a swimming pool.

We will not only see more innovation, allowing our homes to support our “stay-at-home” lifestyle, but we will also see a trend toward simpler fixtures, cabinets, and color palettes within the home. While “simpler” is the overarching theme, families are looking more room, rather that more rooms. Open concept is now ubiquitous , but the pandemic experience of 2020 has retrained homeowners to appreciate more a variety of separate rooms -- home office, media room or home theatre, the ability to close off the living room, and maybe a separate den. Handy when EVERYONE is home ALL DAY AND NIGHT! A more closed concept space gives a family options for togetherness, and still allow some space for family members to “get away” and do their own thing at times. presents the option of family time and togetherness, but still allows some space for everyone to do their own thing. This could become especially desirable if family members are working from home and have kids that are attending school virtually.

Particularly desirable in 2021:

Home offices -- for work or school
Finished basements -- for returning kids or as an escape
Energy/utility efficiency -- use climbs with more occupants
More storage -- for anything from returning kids items to toilet paper stockpiles
Outdoor space -- where the family can relax and enjoy

So, “at the end of the day,” a custom home can certainly be worth the required extra time and cost. Just look out for costly delays and cost overruns in labor and materials.

Land Survey Blog

Do I need a survey to build a fence or ADU?

Many Ventura Homeowners Ask If A Formal Survey Is Required

Custom Home Plans for 2021

Custom Homes in 2021 Will Reflect the “Safer at Home” Experience of 2020