YOUR CUSTOM HOME AND COMMERCIAL CONTRACTOR

  • Scenic view of a calm lake surrounded by autumn trees with vibrant orange, yellow, and green leaves, reflecting in the water, with rolling hills in the background and a dirt road on the right side.
  • Scenic view of a lake surrounded by colorful autumn trees with mountains in the background under a partly cloudy sky.

Our Services

  • New Construction icon

    New Construction

    Specializing in high-quality new construction services across Maine. Whether you're building a custom home or residential development, our experienced team delivers expert craftsmanship, local knowledge, and personalized service from the ground up. From planning and permitting to the final walkthrough, we build with integrity—on time and on budget.

  • Additions icon

    Custom Additions

    Expand your space without compromising your home’s character. We build custom additions that seamlessly blend with your existing structure while meeting your evolving needs. Whether it’s a new bedroom, sunroom, garage, or expanded living area, our Maine-based team ensures quality craftsmanship, thoughtful design, and smooth project management every step of the way. Let us help you reimagine your home—beautifully and practically.

  • Commercial Construction icon

    Commercial Building

    From ground-up construction to tenant fit-outs, we deliver dependable commercial building solutions across New England. We work closely with business owners, developers, and architects to bring commercial spaces to life—on schedule and within budget. Whether you're building a retail center, office space, or industrial facility, our experienced team ensures top-tier craftsmanship, code compliance, and attention to detail from start to finish. Let us build the space your business needs to grow.

  • Green Building icon

    Green Building

    Build smarter, healthier, and more sustainably with 4K Builders. Our green building services prioritize energy efficiency, eco-friendly materials, and long-term performance—without sacrificing style or comfort. Whether it's a new home, addition, or commercial project, we integrate sustainable practices that align with the area’s natural beauty and your environmental goals. From design to construction, we’re committed to building a better future—one structure at a time.

Our Projects

  • Cocheco River Home Rendering

    Cocheco River Home

  • Great East Lake Addition

    Great East Lake Addition

  • Cocheco River Home

    Cocheco River Home

  • Great Lake East

    Great East Lake Renovation

A person is using a power saw to cut a piece of wood, with sawdust flying around.

Ready to Build Your Vision?

Let’s bring your vision to life. Whether you're planning a new build, custom addition, or commercial project, 4K Builders is here to guide you every step of the way. We make the process clear, collaborative, and stress-free—from the first consultation to the final walkthrough. Ready to get started? Contact us today to schedule a conversation and take the first step toward your dream space.

Building Homes as a Family

The Kidney’s — all 4 of us (the 4 “K’s” in 4K) — started this company as a family business and we treat every project like it’s for our own family, because we know that building a home or business is more than just construction; it’s about creating spaces where life happens.

As a family-owned and operated company, we bring trust, care, and commitment to every job. We listen closely, communicate openly, and build with heart. When you work with us, you’re not just hiring a contractor—you’re joining a family that’s dedicated to building your dreams.

What Our Clients Say

  • "I've worked with Seamus for over 5 years now and hope to continue for many more. Seamus and his team have always brought the upmost care to all the projects we've done together and always worked hard to exceed our expectations"

    Zachary Smith, AIA