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Bay State Remodeling

Design-build remodeler serving Greater Boston. Kitchens, bathrooms, whole-home renovations, and additions, one project lead from design through completion.

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121B Tremont St., Suite 24
Boston, MA 02135
(617) 397-5158
info@baystateremodeling.com
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Services

  • Kitchen Remodeling
  • Bathroom Remodeling
  • Whole House Remodeling
  • Basement Remodeling
  • Attic Remodeling
  • Additions / ADU
  • How we work

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© 2026 Bay State Remodeling. Serving Greater Boston since 2007. All rights reserved.
Licensed & insured in MA · HIC #169948 · CSL CS-110634 · Written proposals, always · One project lead per home · Greater Boston service area.
    1. Services
    2. /
    3. Additions and ADUs
    4. Service overview

    Additions and ADUs, designed and built by one team.

    Room additions, second stories, and accessory dwelling units. Zoning and permits handled by us, built by one team.

    Book a ConsultRead the Complete Additions and ADU GuideVisit the showroom
    Garland Rd. Newton whole-home remodel with blue-gray siding, white trim and an attached two-car garage

    Second story and expansion, Garland Rd., Newton

    Additions and ADUs start with the town, not the drawing: zoning, setbacks, lot coverage, and the permit path decide what can be built. We handle that work, then design and build the addition so it reads as original to the house. Our carpentry and finish work is performed by our own dedicated team, not a rotating cast of unknown crews. Licensed trades such as plumbing and electrical are coordinated and supervised by us. Licensed in Massachusetts, HIC 169948 and CSL CS-110634, verifiable at mass.gov.

    What’s included

    What comes with your addition or ADU project

    • •Zoning and feasibility review, permits and inspections handled by us
    • •Architectural and structural design with stamped engineering where required
    • •Foundation, framing, roofing, and exterior tie-in to the existing house
    • •Kitchen and bath in the new space, with selections from our showroom
    • •Framing and finish carpentry by our own dedicated team; plumbing, electrical, HVAC, insulation, and paint coordinated and supervised by us
    • •A dedicated field Project Manager and Operations Coordinator, daily jobsite photos, and a punch list before completion
    Cost

    What will it cost?

    Your first payment is a flat Design and Planning fee that counts toward your project total. The Proposal is a firm price and a mutual commitment; the Contract confirms it after measurements and is not a renegotiation. Plan for a possible deviation of up to 10 percent from the estimate as standard budgeting guidance. Scope changes you request are handled by change order.

    See the tiers and what each includes →
    Bay State Kitchen Gallery

    See it before we build it

    If your project includes cabinets, countertops, or hardware, explore those selections in our own showroom in Waltham.

    Visit the showroomCompare cabinet lines
    Cabinet display with door samples in our Waltham showroom, Bay State Kitchen Gallery
    Our Waltham showroom
    Proof

    Recent additions

    • Finished attic space with dormer windows, built-in window seats, and recessed lighting, Garland Rd., Newton.

      Garland Rd., Newton

      A whole-house remodeling project on Garland Road in Newton transformed a small home into a 5,500 square foot residence. The project involved installing a…

      See the project
    • Renovated Trowbridge Ave. Newton bathroom with wood vanity, quartz counter, chrome fixtures, and pink hand towels

      Trowbridge Ave., Newton

      Bay State Remodeling skillfully created a new bathroom addition from scratch, seamlessly integrating it with their existing primary bedroom space.

      See the project
    What real projects cost in finishes →
    “Completely remodeled our condo. Ray, Roger, and David worked seamlessly, professional, accommodating, and ensured we are happy customers.”

    Elizabeth J. (Google)

    Read the Complete Additions and ADU Guide

    Vetting, permits, timeline, construction costs, and our full process for an addition or ADU project.

    Tell us which room

    A 30-minute call is enough to scope most projects.

    A showroom visit is where it gets real.

    Book a consultVisit the showroom