Free checklist · Southern California edition

Know what you can build before you buy, design, or sign.

50 checks for Orange County and Los Angeles properties: zoning, fire and earthquake zones, LA’s methane and protected-tree rules, the 2025 Energy Code, and exactly what state ADU law lets you build. The surprises that blow up budgets, found while they’re still cheap to plan around.

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  • Which building department and zoning rules actually govern your lot
  • The hazard maps that change your roof, foundation and insurance
  • State ADU and SB 9 numbers, taken straight from the Government Code
  • 12 red flags to price before you commit, plus a one-page property worksheet

What’s inside

Eight sections, in the order they’ll bite you.

01

Jurisdiction & zoning

Who issues your permits, floor-area caps, overlays, the Coastal Zone, HOAs and Mello-Roos.

9 checks
02

Natural hazards

Fire Hazard Severity Zones and Chapter 7A, fault and liquefaction zones, flood maps.

7 checks
03

Soil, site & utilities

Soils reports, LA methane zones, the sewer lateral, service capacity, easements.

8 checks
04

Trees, neighbors & street

LA’s protected trees and shrubs, heritage trees, construction hours and staging.

6 checks
05

Energy & green code

The 2025 Energy Code: solar, heat pumps, batteries, EV-ready garages, CALGreen.

7 checks
06

ADU & lot potential

State ADU minimums, heights, the 60-day clock, impact fees and SB 9 lot splits.

7 checks
07

Owner-builder readiness

Whether you qualify under B&P 7044, when you become an employer, lenders.

6 checks
08

Red flags + worksheet

Twelve things to price before you commit, and one page to record every answer.

12 flags

Local, not generic.

Methane zones, LA’s protected-tree list, OC’s master-planned HOAs, the 2025 fire maps. The rules that differ from what a national checklist tells you.

Sourced, not guessed.

Every state number cites its code section, checked against the statute and agency guidance as of September 2026.

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Fifty questions now, or one very expensive one later.

Get the free checklist