Contour Survey

ADU Surveys & Site Plans for Permit Applications

The survey work your ADU permit actually needs — scaled site plan, verified property lines, and slope data — delivered before your designer draws a single wall.

Start Your ADU on Solid Ground

Pre-construction surveys for accessory dwelling units across the East Bay — the scaled site plan, boundary verification, and topographic data Bay Area cities require before an ADU permit application is accepted. California law makes ADU approval ministerial with 4-foot side and rear setbacks, but those setbacks are measured from your true property line, not your fence — and every city's checklist starts with a site plan drawn to scale showing property lines, existing structures, easements, and utilities. We deliver a surveyor-prepared base map your designer builds directly on, staked property corners so the 4-foot setback is real, and 1-foot contours where sloped lots or city checklists demand them.

  • Scaled site plan base map matching city ADU checklists
  • Boundary verification — 4-ft setbacks measured from the true line, not the fence
  • Property corners staked for design and construction
  • 1-foot contours and drainage data for sloped lots
  • Easement and utility locations from record research
  • CAD-ready DWG base file your designer builds on directly
  • Foundation form verification when the inspector requires it
Laser scanner setup transitioning into dense point cloud data
Reality Capture
Drag reveal

Reality Capture

Point clouds that become usable project files.

High-density scan data supports CAD, BIM-ready modeling, field verification, and existing-condition coordination.

Point cloudScan-to-CADBIM-ready

Typical Deliverables

Stamped site plan base map to your city's ADU checklist

Layered DWG/DXF file your designer draws on directly

Staked property corners at the ADU footprint

1-foot contours, spot elevations & drainage data where required

Why ADU Projects Fail at the Property Line

State law lets you build an ADU just 4 feet from your side and rear property lines — which means most East Bay ADUs are designed right up against the setback. That only works when the line itself is known. Three problems show up over and over:

The fence is not the line

In East Bay neighborhoods platted a century ago, fences routinely sit a foot or more off the legal boundary. Design a 4-foot setback from the wrong line and the error surfaces at final inspection — after the foundation is poured.

The checklist wants real data

City ADU checklists require the lot drawn to scale with property line dimensions, setbacks, easements, and utilities. Some are explicit: Fremont requires a boundary survey when an ADU sits within 24 inches of a minimum setback, and Pleasanton wants 1-foot contours for detached units.

Slopes change everything

On hillside lots in Oakland, Berkeley, and Lamorinda, grading, drainage, retaining walls, and foundation design all hang on accurate existing-ground contours — and hillside plan checkers know the difference between measured and guessed.

1

Checklist Review

We confirm your city's ADU submittal requirements — site plan content, survey triggers, slope and drainage items — so the survey is scoped to what plan check will actually ask for.

2

Boundary & Records Research

We research your deed, recorded maps, and easements, then locate existing monuments to establish where your property lines actually are.

3

Site Survey

One laser-scanned site visit captures structures, hardscape, trees, utilities, and terrain — spot elevations and contours included where the lot slopes or the city requires them.

4

Deliverables

You receive a stamped site plan base map and layered DWG file sized to your city's checklist, with property corners staked on the ground for your designer and builder.

ADU Surveys FAQ

It depends on the city and how close you build to a property line. Every Bay Area city requires a site plan drawn to scale showing property lines and setbacks, and many make a survey explicit — Berkeley requires one for all new construction, Oakland within 3 feet of a line or on slopes over 20%, Lafayette within 5 feet of a setback, Fremont within 24 inches of one, and Concord's checklist says site plans should be based on a licensed surveyor's work. Even where no survey is formally required, the 4-foot setback is measured from the legal boundary, and fences in older East Bay neighborhoods are commonly a foot or more off the true line.
City checklists typically require the lot drawn to scale with property line dimensions, all existing and proposed structures with setback distances, easements of record, utility locations, and existing trees. Sloped lots often add contours, drainage direction, and earthwork quantities — Pleasanton calls for 1-foot contours for detached ADUs, Moraga requires topography on every ADU site plan, and Piedmont wants 2-foot contours with lot-line coordinates on every application. A surveyor-prepared base map covers all of it in one deliverable.
They can draft it, but they need accurate data underneath — property line locations, setback distances, and elevations. A designer working from the assessor's parcel map or a tape measure off the fence inherits whatever error those sources carry, and a setback violation discovered at final inspection can mean tearing into a finished structure. Our base map gives your designer measured, stamped data to draw on.
Not necessarily. Even where the submittal checklist is silent, field inspectors frequently require a licensed surveyor to verify that the foundation forms conform to the approved plans before the pour — Albany and Fremont have written that practice into their rules, and inspectors elsewhere impose it case by case when forms sit close to a line. If that request lands mid-construction with no boundary established, the surveyor has to do the full research and fieldwork on a rush schedule. Starting with a comprehensive survey means design gets accurate data and form verification is a quick return visit instead of a project delay.
Sloped lots usually need a topographic survey with the site plan — grading and drainage design, retaining walls, and foundation stepping all depend on accurate existing-ground contours, and hillside cities in the Oakland, Berkeley, and Lamorinda areas scrutinize this closely. Our laser-scanned topo delivers 1-foot contours, a terrain model, and drainage flow data from the same site visit as the boundary work.
They can. Parcels mapped in FEMA A, AE, or AO zones may need elevation certificates with the application — Dublin's ADU checklist, for example, requires two elevation certificates for properties in those zones. We prepare FEMA elevation certificates and can confirm your parcel's flood zone status before you submit.
Most East Bay ADU site plan surveys fall in the range of a combined boundary and topographic survey for a residential lot — typically $1,500 to $3,500 depending on lot size, slope, vegetation, and how much boundary research the neighborhood requires. It is a small fraction of ADU construction cost, and far cheaper than relocating a structure that encroached into a setback.

Boundary Determination

Establish clear, legally defensible property boundaries with a licensed Bay Area boundary surveyor — including difficult boundaries on hillside lots, irregular parcels, post-1906 SF blocks, fire-rebuild areas, and properties with conflicting record evidence.

Site Plan Surveys

Stamped site plan surveys, boundary + topographic base maps, and existing-condition documentation for Bay Area permit submittals.

Topographic Surveys

Survey-grade topographic mapping for East Bay and Bay Area properties, captured with a Trimble terrestrial laser scanner (TLS).

ADU Surveys Across the East Bay

Local conditions, permitting, and county recording differ city to city — see how we handle adu surveys where your property is:

OaklandBerkeleyPiedmontAlbanyAlamedaSan LeandroEl CerritoRichmondWalnut CreekConcordLafayetteOrindaMoragaMartinezPleasant HillEl SobranteRodeoBeniciaVallejoAntiochPittsburgBrentwoodPinoleHerculesKensingtonCrockettEmeryvilleSan Pablo

Planning an ADU?

Send us your address and city — we'll confirm what your ADU checklist requires and quote the survey scope that gets your application accepted the first time.

Get a Quoteor(510) 543-2220

Meeting-first estimates • Response within 24 hours • Serious projects only

Call (510) 543-2220Get a Quote