Every Phase 1 LA-area city's junior adu (jadu) cost page, in one place, sorted by cost-tier.
Conversion of an existing interior space (typically a bedroom + adjacent bath) to a JADU, ≤ 500 sqft, with efficiency kitchen.
California typical range (2026): $55,000–$130,000 standard tier across LA-area cities.
What anchors the schedule: JADUs use a separate, lighter permit track than ADUs; owner-occupancy requirement is the recurring constraint.
Junior ADU (JADU) cost, Junior ADU (JADU) cost Los Angeles, Junior ADU (JADU) cost California, Junior ADU (JADU) permit, TRUbee project hub, construction cost comparison.