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G.M. Roth Design Remodeling
12 Murphy Drive, Unit G
Nashua NH, 03062
603-421-6631
Monday - Friday: 10am - 5pm
Showroom by Appointment Only
ADU Builders
Home > ADU Builders

Build a Beautiful, Legal ADU in NH & MA

New 2024–2025 state laws make ADUs easier than ever. Let G.M. Roth Design Remodeling guide you.

Whether you’re planning for family, future needs, or additional income, our Design–Build team handles everything — zoning, design, permits & construction.

A backyard with an ADU

Why Homeowners Choose G.M. Roth Design Remodeling for ADUs

  • 40+ Years Local Experience
  • True Design–Build Process
  • Expert ADU Zoning & Codes Guidance
  • Aging-in-Place Certified Design (CAPS)
  • Transparent Pricing & Detailed Plans

ADUs create flexible living space that adapts with your life:

Aging in Place / In-Law Suite

Give parents or relatives a private, safe, accessible home connected to yours.

Multigenerational Living

Let adult children move back while maintaining privacy and independence.

Potential Rental Income (Town-dependent)

Some communities allow long-term rentals — a major financial advantage.

Guest Suite, Home Office, or Caregiver Quarters

A separate space adds versatility to your home.

Boost Resale Value

Buyers prefer homes with legal, well-designed ADUs.

NEW ADU LAWS (2024–2025)

The rules changed — and homeowners now have MORE rights.

Massachusetts

Affordable Homes Act (2024 – H.4977 / Chapter 150)

  • ADUs now allowed by right statewide in single-family zoning
  • Up to 900 sq ft or ½ of the primary home
  • Limits on restrictive parking requirements
  • ADU cannot be unreasonably blocked or restricted by towns
  • Local rules still apply, but the state now overrides unnecessary barriers

New Hampshire

RSA 674:71–73 + HB 577 (Effective 2025)

  • Towns must allow at least one ADU on any single-family lot
  • Expanded rights for detached ADUs
  • Clarified septic rules so towns can’t demand oversized systems
  • Expanded allowable size and layout flexibility
  • Greatly improved homeowner rights for backyard cottages & additions

WHAT TYPE OF ADU DO YOU WANT TO BUILD?

Choose from the most popular ADU models:

Attached ADU / In-Law Suite

Connected to the main home with shared utilities.

Detached Backyard Cottage

Perfect for privacy, multigenerational living, or flex space.

Garage Conversion ADU

Add a complete living unit above or within an existing garage.

Basement / Lower-Level Apartment

Cost-effective ADU solution using existing space.

OUR DESIGN–BUILD ADU PROCESS

You’re not managing architects, contractors, engineers, and zoning boards — we do all of it.

1. Discovery & Site Review

We assess your property, goals, and what’s possible under local ADU regulations.

2. Zoning & Feasibility

We evaluate setbacks, septic, utilities, lot coverage, and your town’s bylaw.

3. Concept Design + Budget Range

Layouts, 3D renderings, and an accurate cost range based on real builds.

4. Architectural Plans & Engineering

Full drawings for structure, mechanicals, and code compliance.

5. Permitting & Approvals

We handle all submissions and communicate with your town.

6. Construction & Project Management

A clean, efficient process with a dedicated project manager.

7. Final Walkthrough & Warranty

Your ADU is delivered move-in ready, with ongoing support.

Ready to Explore an ADU on Your Property?

Whether you’re planning for family, flexibility, or long-term value, we’ll help you understand what you can build — and how to build it right.

Schedule Your ADU Consultation
Request ADU Feasibility Review

    Complimentary Consultations







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    Serving:
    Nashua, Hudson, Merrimack, Litchfield, Hollis, Brookline, Amherst, Milford, Wilton, Lyndeborough, Mont Vernon, Pelham, Windham, Londonderry, Derry, Manchester, Bedford, Goffstown, Hooksett, Auburn, Candia, Chester, Raymond, Deerfield, Francestown, Greenfield, Mason, New Boston, Greenville, Temple,Tyngsborough (MA), Dunstable (MA), Groton (MA), Pepperell (MA), Townsend (MA), Ashby (MA), Dracut (MA), Lowell (MA), Chelmsford (MA), Westford (MA), Littleton (MA), Ayer (MA), Shirley (MA), Tewksbury (MA), Billerica (MA), Carlisle (MA), Acton (MA), Boxborough (MA), Harvard (MA), Lancaster (MA), Lunenburg (MA), Fitchburg (MA), Leominster (MA), Clinton (MA), Bolton (MA), Hudson (MA), Marlborough (MA), Stow (MA)

    Customer Pledge

    We pride ourselves in the fact that more than half of our projects come by way of referral from previous clients! Because we appreciate your trust and confidence, and because your satisfaction is central to our core values, we pledge to:

    • Construct your project using quality, up-to-date materials and construction techniques.
    • Communicate with you honestly and fairly
    • Provide detailed specifications.
    • Treat you and your property with respect.

    We want you to be delighted with our work, and will make every effort to see that you are.

    Guild Quality’s 2023 Guildmaster Awards Honors G.M. Roth Design Remodeling with the designation Guildmaster with Distinction

    G.M. Roth Design Remodeling of Nashua, NH received the 2023 Guildmaster with Distinction award from Guild Quality for demonstrating exceptional customer service!

    Our Staff
    Senior Management Team
    Gerry Roth, CGR,CAPS, MASS, CSL
    President
    Dean Rascoe
    Director of Sales and Marketing
    5 years of service
    Taylor Barry
    Accounting/Office Manager
    5 years of service
    Spencer Roth, CAPS, Mass. CSL
    Director of Production
    5 years of service
    HEATH COXALL, MASS. CSL
    DIRECTOR OF OPERATIONS
    View All Our Staff

    Customer Testimonials

    Customer satisfaction is the cornerstone of our success since our founding in 1986. We pride ourselves in the fact that more than half of our new projects come by way of referral from previous clients! Read more about our Customer Pledge

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      This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. By clicking "Submit", you are agreeing to have GM Roth Design Remodeling contact you about products and services and keep you informed about our company in the future. We may use an auto-phone system to contact you by phone or text. You do not need to make a purchase or submit this form but instead can call 603-880-3761 to speak with us Please be aware that all calls are recorded for quality and safety purposes.

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      Gerry Roth
      Gerry Roth, CGR,CAPS, MASS, CSL
      President
      GRoth@gmroth.com
      • Certified Graduate Remodeler
      • Certified Aging In Place, Designate Secretary Of The NH BBB
      • Past President Of New Hampshire Home Builders & Remodelers Association (NHHBRA)
      • Licensed Massachusetts Construction Supervisor

      While Gerry contributes in many ways to the business he founded over 35 years ago, his leadership is most evident in the form of taking clients’ input and converting it to reality in their homes. In addition to supporting and directing design team members on their projects, Gerry spends most of his time working on Design Build projects, using his knowledge of construction techniques and well developed design skills to guide clients from initial consultation through project development and on to project completion. Many of Gerry’s projects have won industry awards and accolades over the years. Gerry also takes an active leadership role in the construction industry, working with other business leaders to improve our ability to serve homeowners.

      Dean Rascoe
      Dean Rascoe
      Director of Sales and Marketing
      5 years of service
      DRascoe@gmroth.com
      • Marketing Degree From The School Of Business At The University Of Massachusetts

      Dean has delivered consistent results in sales and marketing leadership positions in diverse markets. He is responsible for driving and managing the continued growth of the company while ensuring excellent client service. He is focused on exceeding client expectations. His extensive sales and marketing experience combined with his passion for remodeling allow him to utilize his unique skill set to ensure G.M. Roth continues to deliver client dreams while building long-term relationships. He enjoys running, playing soccer and golfing with his wife and two daughters.

      Taylor Roth
      Taylor Barry
      Accounting/Office Manager
      5 years of service
      TBarry@gmroth.com
      • BS In Corporate Finance & Accounting From Bentley University; Minor In Psychology

      Taylor has over seven years of accounting experience in various industries – banking, publishing and remodeling. Math has always been her strong suit and she loves nothing more than when things balance. At G.M. Roth, Taylor is responsible for preparing and maintaining the financial statements while overseeing all billing, invoicing, accounts payable, payroll and financial reporting functions. She also is the Human Resources Administrator, handling employee benefits and onboarding. In her free time she enjoys reading, spinning, hiking, and traveling.

      Spencer Roth
      Spencer Roth, CAPS, Mass. CSL
      Director of Production
      5 years of service
      SJRoth@gmroth.com
      • BS In Civil Engineering From Northeastern University, Massachusetts Supervisor License, EPA/HUD RRP Certified Renovator, Certified Aging In Place

      Spencer worked as a Civil Engineer after school, before joining the family business, and prides himself in ensuring projects run as smoothly as possible, end on schedule, and surpass client expectations. Enhancing the lives of others by producing remodeling projects of the highest quality is his goal, each and every day. In his limited personal time, Spencer plays hockey and golf and enjoys live music. He has become a very reliable part of the team, who has proven to be an innovative professional while retaining a spirited character. He has a good sense of humor and can make others smile while getting the job done.

      Heath Coxall
      HEATH COXALL, MASS. CSL
      DIRECTOR OF OPERATIONS
      HCOXALL@GMROTH.COM
      • BA In Communications From Worcester State University
      • Massachusetts Construction Supervisor License
      • EPA/HUD RRP Certified Renovator
      • OSHA 10

      Heath has a proven track record of success leading teams of sales and production personnel in various industries over the last 25 years. He has an extensive background in construction, emergency restoration, reconstruction, and sales. He is responsible for removing obstacles and barriers, which allows the sales and production teams to achieve their goals. In his free time Heath enjoys spending time with his 4 children, wife, and dog while hiking Acadia National Park and other local trails.