ADU — Detached 1-bedroom Cost in San Diego, 2026

Why detached 1-bedroom × San Diego produces this band

A detached 1-bedroom scope for a adu in San Diego combines two price levers: scope and metro labor rates. A detached 1-bedroom ADU is the category anchor: 500-750 SF standalone unit with a full kitchen, full bath, and bedroom. Separate foundation, roof, MEP, and entrance. Against the national median remodel labor rate, San Diego runs 35% above the national median — so the detached 1-bedroom band comes in at the mid-range, then scales 35% above the national median on top of that. Permit timelines for residential work in San Diego typically run 6-14 weeks, which is the window you plan your design and decision sequence against. This page gives you the actual 2026 San Diego bands for this exact combination, plus the three cost drivers Baily asks about first when scoping the project live.

What drives cost for a detached 1-bedroom scope

• ·New foundation (slab-on-grade or stem-wall)
• ·New roof system and weather envelope
• ·Full MEP rough-in from the street (water, sewer, gas, electric)
• ·Site prep, grading, drainage

What makes San Diego different

• Labor — CSLB-licensed GC market with strong ADU-construction demand following SB 9 and SB 10.
• Labor — Coastal Commission jurisdiction adds project-management time for parcels west of the 1st public road.
• Labor — Military-base proximity generates steady remodel demand (off-base housing), keeping trades busy year-round.
• Material — Title 24 energy requirements same as LA — higher envelope + glazing spec.
• Material — Coastal corrosion protection required on hardware and fasteners within 1,500 ft of the ocean.

San Diego rules that affect this scope

• San Diego Development Services Department (DSD) handles plan check — timeline varies by review type and discretionary vs ministerial.
• Coastal Development Permit required within the Coastal Zone — adds 4-12 weeks.
• San Diego ADU Bonus Program allows additional ADUs above state minimums with deed-restricted affordability.
• Fire-prone hillside parcels subject to ember-resistant construction under Chapter 7A of California Building Code.

Scope your adu with Baily.

Baily asks the eight questions that determine where your project lands inside the $243K-$513K band for San Diego and hands the scoped brief to one licensed builder.

Related pages

Questions LA homeowners actually ask

• What is the 2026 cost range for a detached 1-bedroom scope adu in San Diego?

  $243,000-$513,000, with the median landing near $378,000. The range reflects finish tier and layout complexity within the detached 1-bedroom scope; the San Diego labor multiplier of 1.35× vs national median is baked in.

• How long does a detached 1-bedroom scope adu take in San Diego?

  26-40 weeks of on-site construction for the detached 1-bedroom scope, plus 6-14 weeks of permit review in San Diego if the scope requires a permit. Cosmetic-only refreshes often skip permits; anything touching plumbing, electrical, or structural does not.

• What is the single biggest budget-overrun risk for this scope?

  Sewer connection — if the existing lateral runs under the new foundation line, a new lateral cut plus utility easement and right-of-way bond can add $12-22K.