Expert Home Addition Contractor with Legacy Construction

A great addition looks like it was always there. We design and build seamless additions, fully integrated with your existing home, from architecture through finished interiors.

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A home addition is not just more square footage. It is a structural integration that has to match your home architecturally and perform for decades. That distinction is where most additions succeed or fail. Legacy Construction has built additions that are indistinguishable from the original structure — roofline, siding, trim, and all.

What we bring to every project:

  • We show up when we say we will
  • We build exactly what we said we'd build
  • We never leave a project unfinished
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30+

years of combined experience

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250+
completed projects
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$300M+
in managed project value

TESTIMONIALS

Hear from some Southern Maine

homeowners we've helped

Five black stars.

Watching our home transform through this addition was incredible. Legacy Construction communicated clearly, respected our space and vision, and delivered work that feels solid and intentional. You can tell they care about doing things the right way—and building work that lasts.

Jennifer C.
A newly poured concrete pad in a gravel area, with trees in the background under a blue sky.
Five black stars arranged horizontally.

Legacy Construction built an addition onto our home, and the quality is outstanding. The new space blends perfectly with the original house. They worked with us on budget and design and were always upfront about costs and options. Very professional from start to finish.

Savannah B.
Interior view of a cabin with wood walls and ceiling, wood-burning stove, and a dark floor.
Five black stars in a row.

From the first meeting, Legacy Construction was honest, professional, and easy to work with. They walked us through budget, design, and expectations clearly and followed through on everything. The end result is a beautifully built space that feels solid and well thought out.

Mehak K.
Two-car garage with tan doors, brown roof, and a driveway in front of a house against a clear blue sky.
Legacy Construction Service Area

Built to match. Built to last.Structural integration done right.

Every addition we build is designed to match your home architecturally and perform structurally. We manage the full project so you stay focused on your life, not your job site.

  • Evaluation, Design, and Full Structural Integration

    We begin with a thorough evaluation of your existing home, its structural system, foundation type, roofline, and siding, to understand how an addition connects to all of it. We then develop architectural plans that extend your home in a way that looks and performs like original construction.

  • What Sets Legacy Apart on Addition Projects

    Homeowners hiring for an addition get a builder licensed in both construction and real estate, a team that has managed projects worth hundreds of millions, and a warranty five times longer than the Maine standard. We keep four to six active projects at any time so your addition never competes for attention.

  • Cost, Timeline, and What to Expect

    A single-room addition in Southern Maine typically runs $80,000 to $150,000 depending on size, finish level, and structural scope. Larger additions with full mechanical systems or second stories can reach $200,000 or more. Timelines for most additions run twelve to twenty weeks. Legacy Construction sets fixed-price contracts before breaking ground and backs every addition with our full warranty package.

We coordinate all permits, schedule every inspection, and manage the full project so nothing falls through the cracks on your property. Contact us to start planning yours.

Bright white sunroom addition on a beige house, bordered by blue hydrangeas and stone garden paths
Bright farmhouse kitchen with white cabinets, wood beams, and large windows over a wooden floor

Count on Legacy Construction for your  Home Addition Contracting needs

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Customer Satisfaction

We offer a 2-year warranty on all of our work, so you can have peace of mind knowing it'll be done right the first time.

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Built on Repeat Business

70% of our clients come back for another project. That kind of return rate tells you more about our work than any sales pitch could.

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Full-Scope Construction

No matter the scope or scale of your project, we handle every phase of the build from start to finish with our own crew on site.

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Insured and Accountable

We carry full insurance on every project we take on, and we put our 2-year warranty in writing so you know exactly what backs the work.

Our easy 3-step process for perfect Home Addition Contracting

1

ARRANGE YOUR ADDITION CONSULTATION APPOINTMENT.

Contact us to discuss your space requirements, budget considerations, and existing home conditions so we can design an addition that works with your property.

2

WE'LL CONSTRUCT YOUR SEAMLESS ADDITION.

Our team executes construction with structural precision, architectural matching, and careful management of your occupied home throughout the project.

3

ENJOY YOUR EXPANDED HOME IMMEDIATELY.

We deliver your finished addition with architectural harmony, completed on schedule and built to look like it was always part of your home.

Small white backyard outbuilding with glass door and black awning beside a house and lawn

Frequently asked questions regarding Home Addition Contracting

  • How much does a home addition cost in Southern Maine?
    A single-room addition typically runs $80,000 to $150,000 depending on size and scope. Larger additions can reach $200,000 or more. Legacy Construction provides a fixed-price contract before breaking ground.
  • How long does a home addition take?
    Most home additions run twelve to twenty weeks from groundbreaking to final walkthrough. Larger additions with second stories or complex roofline integrations can take longer. Legacy Construction builds the inspection sequence into the schedule from day one.
  • Do you need a permit for a home addition?
    Yes. Home additions require a building permit and depending on scope may require separate electrical, plumbing, and mechanical permits. Legacy Construction manages every permit and inspection for every addition we build.
  • Where do you build additions in Southern Maine?
    Legacy Construction builds home additions across Southern Maine within roughly 30 miles of Portland. Call (207) 544-4607 to confirm whether we cover your area.
  • What warranty covers home additions?
    Every home addition is backed by our full warranty: 1 year on materials, 2 years on systems, 5 years on workmanship, and 10 years on structural coverage. Five times longer than Maine's standard. Everything is in writing before work begins.
  • How do I start an addition project?
    Call us at (207) 544-4607 or fill out the estimate form. We will evaluate your existing home, discuss your addition plans, and put together a written estimate. From there we move into design and planning.