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ADU BuildersPortland, ME

Best ADU builders in Portland, Maine

Looking for the best ADU builders in Portland, Maine? Our directory features 2 vetted adu builders serving the Portland area. Whether you're planning a new ADU construction, garage conversion, or backyard cottage, find the right builder for your project.

2 adu builders found
Average rating: 4.3

Top ADU builders in Portland

Why Choose ADU Builders in Portland?

Portland is one of the top markets for accessory dwelling units in Maine. With growing demand for affordable housing, ADU construction in Portland offers homeowners an excellent opportunity to add living space, generate rental income, or house family members. Our curated list of adu builders in Portland helps you find experienced professionals who understand local building codes, zoning regulations, and permit requirements.

What to Look for in ADU builders

  • 1
    Licensed and insured adu builders with experience in Portland
  • 2
    Knowledge of Portland zoning laws and ADU permit requirements
  • 3
    Portfolio of completed ADU projects in the Portland area
  • 4
    Transparent pricing and detailed project timelines
  • 5
    Strong reviews and ratings from local homeowners
  • 6
    Warranty coverage on construction and materials

Frequently Asked Questions

How much does it cost to build an ADU in Portland?

ADU construction costs in Portland typically range from $150,000 to $350,000 depending on size, design, and finishes. Garage conversions are generally less expensive ($80,000–$150,000), while custom-built detached ADUs can cost more. Get free quotes from our listed adu builders to compare prices.

Do I need a permit to build an ADU in Portland, Maine?

Yes, ADU construction in Portland requires building permits. Maine has specific ADU regulations, and local zoning laws may have additional requirements. Our listed builders can help you navigate the permitting process.

How long does it take to build an ADU in Portland?

ADU construction timelines in Portland typically range from 4–12 months, depending on the project type. Prefab ADUs can be installed in 2–4 months, while custom builds may take 8–12 months including design and permitting.