Arcadia · ADU permits
ADU permits in Arcadia
How to build a ADU in Arcadia: permit pathway through Arcadia Development Services Department, drawings required, local watch-outs, and a free address-level wizard for your Arcadia lot.
Arcadia context
Arcadia's ADU ordinance is in Arcadia Municipal Code Title 9. The city aligns with the California state baseline plus Hillside Standards for slope-affected parcels. Plan check is typically 60 days. The Metro A Line (Gold Line) station at Santa Clara + Wheeler opens up parking-exemption pathways for southern Arcadia parcels.
- Permit agency
- Arcadia Development Services Department
- Median lot size
- 9,500 sqft
- ADU permits issued (2025)
- 291Source: Cal HCD Annual Progress Report 2025 (Table A2, BP_ISSUE_DT1 set)
Arcadia ADU ordinance
Verified against Arcadia Development Services Department's published ordinance on 2026-05-12. State law (CA Government Code §65852.2) overrides any locally-stricter rule.
Max detached ADU size
1,200 sqft (state default)
Max ADU height
16 ft / 18 ft with second-story setbacks
Setbacks
4 ft side / 4 ft rear (state minimum)
Hillside Standards
Apply on slopes over 10%
Lot-coverage + grading rules. Northern Arcadia foothills.
VHFHSZ construction
Class A roofing + ember-resistant venting + fire-rated assemblies
Most of north Arcadia.
Local processing time
60 days for flat-lot ADUs; longer for hillside
Pre-approved standard plans
None city-specific
Drawings you'll need to submit
Type your address. See if you can build an ADU, what kind, and exactly how to permit it.
- Site plan (parcel layout + setbacks)
- Proposed floor plan
- Elevations (each side)
- Title 24 CF1R energy compliance
PermitPathLA generates the site plan free from your Arcadia address. The other drawings come from your architect or plan firm — we list pre-approved options in the wizard.
Arcadia watch-outs for ADU
Overlays that hit a meaningful share of Arcadia lots
Very High Fire Hazard Severity Zone (VHFHSZ)~28% of parcels
Northern Arcadia foothill parcels above Foothill Boulevard.
Hillside Standards~22% of parcels
Slopes over 10% trigger geotech + grading limits.
Alquist-Priolo (AP) Earthquake Fault Zone proximity~4% of parcels
Sierra Madre Fault adjacency on the north city edge.
Local quirks
Arcadia Unified school fees apply
Arcadia Unified School District (AUSD) charges school facility fees on ADUs over 500 sqft. AUSD is consistently one of California's highest-ranked public districts — a primary driver of Arcadia home premiums.
Hillside foothills need geotech reports
Lots above Foothill Boulevard typically need a geotechnical / soils engineering report. Budget $3K-$8K and add 4-8 weeks.
Santa Anita Park traffic affects construction logistics
Santa Anita Park race days (and special-event days like the Breeders' Cup) generate significant local traffic. Schedule construction deliveries around race days.
Run your Arcadia address through the wizard
We pull your parcel polygon from county GIS, apply Arcadia ordinance + state baseline rules, generate the site plan, and walk you through the Arcadia Development Services Department submittal. Free, no signup.