An ADU can create rental income, multigenerational housing, or a flexible guest suite — but success depends on zoning, utilities, parking, and construction cost, not just a pretty plan.
Confirm the site can host an ADU
- Zoning and local ADU ordinances (size, height, setbacks)
- Utility capacity (water, sewer/septic, power)
- Access and parking requirements
- Tree, slope, and drainage constraints
Who you typically need
Most homeowners start with architectural design. Structural engineering is common for detached units or complex foundations. Civil input matters when grading, utilities, or stormwater are nontrivial.
Budget for more than the building
Utility connections, driveway work, landscaping restoration, and furniture often surprise owners. Keep contingency and soft costs in the plan from day one.