Accessory Dwelling Unit (ADU) Construction Cost
ADUs (granny flats, in-law suites) are one of the highest ROI investments due to rental income potential. Many cities have streamlined ADU permitting to address housing shortages.
Low Estimate
$60,000
Mid-Range
$150,000
High End
$350,000
Avg ROI
80%
Interactive Cost Estimator
Mid-grade materials, good quality fixtures, standard options.
Estimated Total Cost
$150,000
Based on 200 sq ft at mid quality. Actual costs vary by location and contractor.
Cost Breakdown
Approx. $75,000 at mid-range pricing
Approx. $75,000 at mid-range pricing
Labor-heavy projects (with high labor costs) benefit most from getting multiple contractor bids. You can save on materials-heavy projects by sourcing materials yourself at contractor pricing.
What Affects the Price
- 1Attached vs detached
- 2Size and bedroom count
- 3Kitchen and bath quality
- 4Local ADU regulations
- 5Utility connections
Popular Upgrades
- Full kitchen
- Separate entrance
- Solar panels for energy independence
Discuss upgrades with your contractor before finalizing the quote. Some upgrades are cheaper to include during initial construction than to add later.
DIY vs. Hire a Pro
Professional installation strongly recommended.
DIY Advantages
- • Save 50% on labor costs ($75,000 at mid-range)
- • Control over timeline and material selection
- • Satisfaction of completing the project yourself
- • Flexibility to work in phases
Pro Advantages
- • Guaranteed workmanship and professional finish
- • Proper permits and code compliance
- • Access to trade pricing on materials
- • Required for safety and code compliance
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