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Around 500 sq ft

500 Sq Ft ADU Plans & Small-ADU Ideas

A 500 sq ft search usually means the goal is a compact, independent backyard home. ADU.zone currently has defined 400 and 600 sq ft planning footprints, so this guide compares those real concepts instead of presenting a made-up 500 sq ft plan.

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What this page gives you

  • Defined model dimensions where ADU.zone has a real planning footprint.
  • Bedroom, bathroom, site-footprint, and intended-use comparisons.
  • A preliminary construction-planning range generated from the current ADU.zone baseline assumptions.
  • A direct path into the property-qualification workflow.

Planning ranges are not bids. Site work, utilities, jurisdiction, access, engineering, selections, and current market pricing can materially change the final project cost.

ADU.zone does not currently publish an exact 500 sq ft standardized footprint. Final size depends on the property, local rules, design priorities, access, utilities, and professional review.

Compare real planning concepts

Start with a defined footprint, then adapt it to the property.

These concepts are planning references, not permit-ready plans. Final architecture and engineering are developed after the site, local rules, utilities, access, and owner priorities are understood.

Studio 400 ADU concept visualization400 sq ftView details

Modern compact

Studio 400

A compact, independent space designed for smaller yards and efficient everyday living.

Studio1 bath20 × 20

Best for: Guest suite, home office, or rental studio

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Cottage 600 ADU concept visualization600 sq ftView details

California cottage

Cottage 600

A true one-bedroom home with clear separation between living, sleeping, and service spaces.

11 bath20 × 30

Best for: Long-term rental or independent family housing

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Planning snapshot

Studio 400: the first concept to test.

Area

400 sq ft

Footprint

20 × 20 ft

Bedrooms

Studio

Bathrooms

1

Stories

1

Preliminary baseline range

$130,000–$160,000

Current ADU.zone baseline for this model with standard starting selections. This is an early planning range only and excludes property-specific verification.

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Site requirements

A model only works when the site works.

Buildable area

Setbacks, easements, existing structures, lot coverage, and required separation can limit the usable footprint.

Access

Construction access, staging, excavation, material delivery, and fire-department requirements can affect design and cost.

Utilities

Electrical, sewer, water, gas removal or electrification, and service upgrades need property-specific review.

Local process

Planning and building requirements, submittal standards, fees, and review times vary by jurisdiction and project conditions.

Property qualification

Do not choose the final ADU from a catalog alone.

Start with the address, test the closest planning footprint, and identify the unknowns before committing to design scope.

Check my property

Start with your property, then talk through the details.

(650) 400-7606ADUcaliforniainc@gmail.comADU California Inc. / ADU.zone84 West Santa Clara Street Suite 730, San Jose, CA 95113, United States