Prefab ADU Comparison (2026)
Compare top modular and factory-built ADUs. Faster timelines, predictable pricing.
Prefab vs. Custom Stick-Built
Prefab / Modular
- ✅ Fixed, predictable pricing
- ✅ Faster site installation (weeks, not months)
- ✅ Less yard disruption
- ❌ Limited design customization
- ❌ Requires crane access (can be costly)
Custom Stick-Built
- ✅ 100% customizable to your lot
- ✅ Better for sloping or tight access lots
- ✅ Matches main house architecture perfectly
- ❌ Subject to weather delays
- ❌ Months of construction noise in yard
Top Prefab Companies
Abodu
$226K+Size: 340-610 sf
Timeline: 4-6 mos
Availability: CA, WA
Note: High-end design, Crane install
Villa
$100K+Size: 400-1200 sf
Timeline: 3-5 mos
Availability: CA, TX, WA
Note: Multiple layouts, Fast permitting
Boxabl
$50K+Size: 375 sf
Timeline: 2-3 mos
Availability: Nationwide
Note: Foldable, Affordable (Long waitlist)
Mighty Buildings
$149K+Size: 400-800 sf
Timeline: 4-6 mos
Availability: CA
Note: 3D-Printed, Eco-friendly
Dvele
$175K+Size: 400-1000 sf
Timeline: 4-6 mos
Availability: CA, OR, WA
Note: Smart home integrated, Passive house
Azure Printed Homes
$60K+Size: 400-1000 sf
Timeline: 3-4 mos
Availability: CA
Note: 3D-Printed from recycled plastic
The "Hidden Costs" of Prefab
The "base price" of a prefab unit rarely includes site prep. Budget an additional $30,000 - $60,000 for:
- • Foundation pouring and leveling
- • Trenching and connecting utilities (water, sewer, electric)
- • Crane rental and street closure permits (for lifting over the main house)
- • Local city permit fees
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