Residential Land Surveying FAQs

A boundary survey is a professional determination of where your property lines actually are on the ground. A licensed land surveyor researches your deed, subdivision map, and neighboring records, then locates and verifies physical monuments (iron pipes, rebar, tags) in the field. The result is marked corners on your property and, when required, a recorded map.

You typically need a boundary survey when you’re:

• Building a fence, wall, or structure near a property line
• Resolving a disagreement with a neighbor about where the line is
• Buying or selling property and want certainty about what you own
• Planning an addition, ADU, or new construction that must meet setback requirements

**Tip: A fence is not a property line. In our experience, existing fences are frequently off the true boundary — sometimes by several feet.

A boundary survey answers “where are my property lines?”

A topographic (topo) survey answers “what does my property look like?” — it maps elevations, slopes, trees, structures, utilities, drainage patterns, and other site features.

If you’re planning a remodel, addition, ADU, pool, retaining wall, or hillside project, your architect or civil engineer will almost always need a topographic survey as the base map for design. Many residential projects combine both into a single boundary-and-topographic survey, which is usually more cost-effective than ordering them separately.

A lot line adjustment (LLA) moves the boundary between two or more existing adjacent parcels — no new parcels are created. Common examples: transferring a strip of land to a neighbor, fixing a garage or driveway that encroaches over a line, or reshaping parcels to make both more usable.

A lot split (subdivision) creates new parcels and requires a parcel map or, under SB 9, an urban lot split application.

Lot line adjustments are generally simpler and faster than subdivisions, but they still require city or county approval, new legal descriptions prepared by a licensed surveyor, and recorded deeds. If either property has a mortgage, the lender typically must consent (a “partial reconveyance” or subordination), which we help coordinate early to avoid delays.

Senate Bill 9 (effective 2022) allows many single-family homeowners in California to:

• Split one lot into two (an “urban lot split”), and/or
• Build up to two units per lot (potentially four units total across a split lot)

Key requirements generally include:

• The property must be in a single-family residential zone within an urbanized area
• Each new lot must be at least 1,200 sq. ft. and roughly 40% of the original lot
• The owner must sign an affidavit intending to occupy one unit for at least 3 years
• The property can’t be in certain hazard, historic, or protected-housing areas

SB 9 projects require a survey, a tentative and final parcel map (or equivalent), new legal descriptions, and coordination with the city or county. Every jurisdiction implements SB 9 a little differently, so the first step is a feasibility review of your specific parcel — something we routinely provide.

Several common certifications fall under this umbrella:

• FEMA Elevation Certificate — documents your home’s elevation relative to the base flood elevation. Lenders and insurers use it to set (and often reduce) flood insurance premiums, and it supports Letter of Map Amendment (LOMA) applications to remove a property from a mapped flood zone.
• Foundation / pad certification — verifies during construction that your foundation or building pad was built at the elevation and location shown on approved plans. Cities commonly require this before framing or final inspection.
• Setback certification — confirms a new structure sits the required distance from property lines.

These certifications must be prepared by a licensed land surveyor or civil engineer. If your city, lender, or insurance company has asked for “a certification from a surveyor,” send us the request — we’ll identify exactly which one you need.

Honest answer: it depends — primarily on the quality of the existing record, terrain, vegetation, lot size, and what deliverables you need. As rough guidance:

• Simple certifications are typically the least expensive
• Boundary surveys on flat lots in modern subdivisions with good monumentation are moderate
• Boundary surveys on older properties with poor records, hillside lots, or heavily vegetated parcels cost more
• Lot line adjustments and SB 9 lot splits involve survey work *plus* mapping, legal descriptions, and agency processing, so they’re the largest scope

We provide a written fixed-fee proposal before any work begins, so you’ll know the cost up front. Beware of quotes that seem too good to be true — an unlicensed or cut-rate “survey” that can’t be recorded or relied upon usually costs more to fix than doing it right the first time.

Typical timelines from authorization:

• Certifications (elevation, pad, setback): often 1–2 weeks
• Boundary or topographic survey: commonly 2–4 weeks, depending on research complexity and field conditions
• Lot line adjustment: a few months, driven mostly by city/county review and lender consent
• SB 9 urban lot split: several months, driven by the jurisdiction’s application and map review process

Fieldwork itself is usually just one or two days — the bulk of the time is record research, calculations, mapping, and (for LLAs and lot splits) agency processing. If you have a deadline — a close of escrow, a permit submittal, a construction milestone — tell us at the start and we’ll build the schedule around it.

Yes, when the scope calls for it. Depending on your project you may see:

• Property corner monuments— durable markers (iron pipes or rebar with a cap or tag bearing our license number) set at your actual corners
• Lath and flagging— temporary wood stakes marking lines, offsets, or proposed improvements
• Construction staking — precise marks that guide your contractor in building foundations, walls, or grading to the design plans

Please don’t remove or disturb monuments — under California law, only a licensed surveyor may set or reset them, and they protect your property rights. If a contractor or landscaper disturbs a corner, let us know so it can be properly restored.

Sometimes — and this surprises many homeowners. Under California’s Land Surveyors’ Act, when a survey reveals certain conditions (for example, a material discrepancy with the record, or when we set new monuments), the surveyor is legally required to file a Record of Survey with the county or a Corner Record documenting the monuments. This isn’t optional or an upsell — it’s a state-law obligation that protects the public record and future owners, including you.

We’ll tell you in advance whether your project is likely to trigger a filing and include any recording fees in our proposal so there are no surprises.

First: don’t build, remove a fence, or escalate until you know where the line actually is. The right sequence is:

1. Get a boundary survey from a licensed surveyor — this establishes the factual starting point

2. Share the results with your neighbor; many disputes end once both sides see the monuments and the map

3. If a real conflict exists (an encroaching structure, a fence long treated as the line), options include a lot line adjustment, an easement or license agreement, or in rare cases legal action

We regularly serve as the neutral technical expert in these situations, and our principals have extensive experience providing expert witness support when disputes do reach attorneys or the courts. In our experience, though, a clear survey resolves the vast majority of neighbor disagreements without litigation.