Rowland Heights · ADU permits
ADU permits in Rowland Heights
How to build a ADU in Rowland Heights: permit pathway through LA County Public Works (Building & Safety), drawings required, local watch-outs, and a free address-level wizard for your Rowland Heights lot.
Rowland Heights context
Rowland Heights is in unincorporated LA County despite proximity to Diamond Bar (incorporated city) and La Habra Heights. Permits run through LA County DPW Building & Safety at the Alhambra office via EPIC-LA. Multigenerational households are unusually common (per Census ACS data) — extended-family ADU builds dominate the local permit mix more than rental-investment ADUs.
- Permit agency
- LA County Public Works (Building & Safety)
- Median lot size
- 6,500 sqft
- ADU permits issued (2025)
- 82Source: HCD 2025 total (1,278) distributed proportionally across 2024 per-area shares. 2024: 95.
Rowland Heights ADU ordinance
Verified against LA County Public Works (Building & Safety)'s published ordinance on 2026-04-15. 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)
Permitting agency
LA County Public Works (Building & Safety), Alhambra office
Not LADBS. EPIC-LA portal for online submission.
Local processing time
60 days from complete submittal (state-mandated)
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 Rowland Heights address. The other drawings come from your architect or plan firm — we list pre-approved options in the wizard.
Rowland Heights watch-outs for ADU
Overlays that hit a meaningful share of Rowland Heights lots
Hillside Management Area (Puente Hills foothills)~30% of parcels
Southern + eastern foothill parcels trigger hillside grading review.
Local quirks
Multigenerational-household ADU demand dominates
Rowland Heights has unusually-high multigenerational-household rates. Most ADUs here are built for extended-family use (in-laws, adult children), not rental investments. Floor-plan design priorities differ accordingly.
Run your Rowland Heights address through the wizard
We pull your parcel polygon from county GIS, apply Rowland Heights ordinance + state baseline rules, generate the site plan, and walk you through the LA County Public Works (Building & Safety) submittal. Free, no signup.