ADU vs. Home Addition: Which Is Right for Your San Diego Home?

When you’re running out of space, two of the most common solutions are building an Accessory Dwelling Unit (ADU) or adding square footage with a home addition. Both can dramatically improve your property — but the right choice depends on your goals, budget, and lot conditions.

What Is an ADU?

An ADU (also called a granny flat, casita, or backyard cottage) is a self-contained living unit with its own entrance, kitchen, and bathroom.

Homeowners in San Diego choose ADUs for:

• Rental income that offsets mortgage costs
• Housing for parents, in-laws, or college-age children
• Guest space with privacy
• Dedicated home office or creative studio

What Is a Home Addition?

A home addition increases the square footage of your existing house. Instead of creating a separate unit, it extends your current layout.

Popular additions across San Diego include:

• Second-story additions in Clairemont, Mission Hills, and La Mesa
• Primary suite expansions in Del Mar and Carmel Valley
• Larger kitchens, family rooms, or sunrooms

ADU vs. Home Addition: Key Differences

• Privacy
  • ADU: Separate entrance, utilities, and complete independence
  • Home Addition: Fully connected to the main home
• Rental Potential
  • ADU: Can generate monthly rental income in places like Encinitas and Oceanside
  • Home Addition: Cannot be rented separately
• Cost
  • ADU: Often $150k–$350k+ depending on size and finishes
  • Home Addition: Typically $80k–$250k+ depending on scope
• Timeline
  • ADU: 6–12 months (permits and construction)
  • Home Addition: 3–9 months
• Design Flexibility
  • ADU: New footprint, more options for layout and privacy
  • Home Addition: Limited by the existing structure
• Resale Value
  • ADU: Adds both space and rental income potential
  • Home Addition: Adds livable square footage but no independent rental unit

Which Option Is Right for You?

• Choose an ADU if you want:
  • Passive rental income
  • Independent space for family
  • Flexibility for changing needs
• Choose a Home Addition if you want:
  • To expand your current lifestyle without creating a rental unit
  • A seamless extension of your home’s design
  • A lower upfront cost and faster utility integration

Why San Diego Homeowners Choose Fabrick

At Fabrick Construction, we’ve delivered both ADUs and home additions across the county — from compact garage conversions in North Park to spacious multigenerational retreats in Carlsbad.

We’re known for:

• Transparent budgeting and clear timelines
• Responsive communication from start to finish
• Local expertise in San Diego’s ADU regulations
• Quality craftsmanship that lasts

Ready to Compare ADUs and Home Additions?

Every property is unique. Whether you’re in La Jolla, Encinitas, Chula Vista, Carlsbad, Point Loma, or anywhere in San Diego County, we’ll help you choose the right path with confidence.

👉 Book your free consultation today and find out whether an ADU or a home addition is the best choice for your home.

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