Question 1

How much does an ADU cost to build in San Diego?

Accepted Answer

ADU costs in San Diego typically range from $150,000-$250,000 for a studio/1-bedroom unit (400-600 sq ft), $200,000-$350,000 for a 2-bedroom unit (600-1,000 sq ft), and $300,000-$500,000+ for a larger detached unit with premium finishes. Garage conversions are typically 30-40% less than new construction.

Question 2

Do I need a permit to build an ADU in San Diego?

Accepted Answer

Yes, all ADUs in San Diego require building permits. California's AB 68 and SB 13 streamlined the process significantly. San Diego now allows ADUs on most single-family lots, with reduced setback requirements and no parking mandates near transit. Permit processing typically takes 4-8 weeks.

Question 3

How long does it take to build an ADU?

Accepted Answer

Construction timelines vary: Garage conversions: 3-5 months. Prefab/modular ADUs: 4-6 months. Custom-built detached ADUs: 6-10 months. Add 1-2 months for design and permitting before construction begins.

Question 4

What's the ROI on an ADU in San Diego?

Accepted Answer

ADUs in San Diego can generate $1,800-$3,500/month in rental income depending on size and location. Most homeowners see their investment pay for itself in 5-8 years. ADUs also increase property value by an estimated 20-30% of construction cost at resale.

Question 5

Can I build an ADU on my property?

Accepted Answer

Most single-family properties in San Diego can now have an ADU thanks to California state law. Key requirements: your lot must accommodate the unit with required setbacks (typically 4 feet for detached), you need adequate utility connections, and the primary residence must remain. Our calculator factors in your specific lot details.

San Diego ADU Cost – Rough Ballpark

Rough range and feasibility call

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