A custom living room addition with a fireplace, built-in shelves and cabinets, a vaulted ceiling, and hardwood floors by Gilmore Building Co.

Custom Additions In Boston MetroWest & Central Massachusetts

Are you dreaming of more space, a better flow, and a home that truly fits your lifestyle, but don't want to move?

An addition might be your best bet. The most successful home additions in Massachusetts start with a clear, structured approach, aligning design, budget, and construction early in the process.

At Gilmore Building Co., we design and build stunning, high-quality additions that blend perfectly with your existing home, enhancing both style and functionality. 

If you’re considering a home addition and want a straightforward design-build process, we’re here to talk through your project.

Ready to Design Your Dream Home Addition?

Let's talk about your home remodeling goals with a no-pressure conversation. Schedule your consultation today.

Expand Your Home Without Compromising How It Works

A well-designed home addition should feel like a natural extension of your home and the existing New England architecture, not an afterthought.

Many homeowners consider an addition because something isn’t meeting their needs: there's not enough space, the layout doesn't flow, or the home no longer supports how they live.

The best additions are thoughtfully integrated to improve flow, function, and long-term livability, rather than just increasing the size.

Gilmore Building Co. approaches additions as part of a larger system by considering how the new space connects structurally, aesthetically, and functionally to the existing home, so the result feels cohesive.

Image of a new kithcen in a home remodel by Gilmore Building Co. in central MA
Image of a home addition with second-story living space and a three car garage in central MA by Gilmore Building Company

Popular Types of Home Additions in Boston MetroWest & Central Massachusetts

The right type of addition depends less on square footage and more on how your home needs to function now and in the future.

In Boston MetroWest and Central Massachusetts, most additions are driven by lifestyle changes like growing families, multigenerational living, or the need to reimagine older homes that no longer fit the way families live. The goal is better space, not just more space.

If you're looking for home addition ideas, here are some of the most popular types of additions we build:

 

In Boston MetroWest and Central Massachusetts, most home additions fall in the range of $500,000 to $1,200,000+, depending on the size, complexity, and level of finish. The main cost drivers are structural work, integration with the existing home, and system upgrades.

It depends on your goals. If you're happy with your location and your home has the potential to be reconfigured, an addition could be a better long-term investment. Moving might seem easier, but it often comes with tradeoffs like higher purchase costs, limited inventory, and starting over in a new area.

Most home additions take about 8-14+ months from design through construction. The timeline depends on the level of planning, permitting requirements, and project complexity. Homes that are older or involve structural changes often require more time upfront to ensure the addition fits seamlessly into your existing space.

Yes! Many additions provide an opportunity to upgrade insulation, air sealing, and mechanical systems. When planned correctly, these improvements can make the entire home more comfortable and efficient, not just the new space.

Need project planning information? Talk with the Builder!

Expand Your Home with Stunning, Seamless Custom Additions

Since 2005, we’ve been transforming homes with expert craftsmanship, cutting-edge building techniques, and a passion for design. Our client-first approach means every addition is customized to your vision, maximizing space, efficiency, and long-term value.

Browse our portfolio and get inspired to create the home of your dreams!

A FEW REVIEWS BY OUR CLIENTS

Photo of new-old-home

"While relocating to New England, we researched 100's of homes on-line and through site visits until our real estate agent showed us a new old home designed and built by Gilmore. Upon arrival at this home, we were immediately impressed by the unique yet classic look of the exterior. The interior layout and detailing showed there are still builders who are proud of what they do. When you see quality, you know it ...."

Photo of School House Styling Home

"The level of professionalism Gilmore brings to a project is excellent.  The design and build process really allowed us to explore and then narrow the project's scope of work with ease.  No other company could have applied the knowledge and architectural expertise needed to help us achieve the historic appearance goals we had.  The completed project exceeded our goals."

Photo of addition

"We can't say enough wonderful things about the work completed and the satisfying experience we had teaming with Gilmore Building Co.  Our project came in ahead of schedule and right on budget.  We love our new addition and our new kitchen and bath.  We would recommend Gilmore Building Co. for any project."

Image of a shingle-style home window by Gilmore Building Company in Central, MA

"After a long search, my wife and I found in the Gilmore Building Co. homes everything we believed to be important in a new home. From the classic New England styling, abundant trim work, top of the line mechanicals and hardware, exceptional layout of the kitchen, custom cabinets and high quality appliances. The quality and craftsmanship built into our home was obvious from the street but even more so when you step through the front door."

Photo of beach front shingle style home

"My husband and I spent over a year working with an architect to design our summer home for our family. The execution, workmanship and temperament of the builder were critical to us. Gilmore Building Co. surpassed our expectations throughout the very satisfying process."

Photo of saltbox style home

"We chose to work with Gilmore Building Co. because they presented themselves as offering a detailed project scope and budget, high-quality work and overall excellent communication. And indeed that is what we received - an overall seamless and successful project with a level of customer service and detail not normally seen in this industry. We would highly recommend Gilmore Building Company and look forward to working with them again on future projects."

Ready to Design Your Dream Home?

Let's talk about your home remodeling goals with a no-pressure conversation. Schedule your consultation today.

Where We Work

Gilmore Building Co. works throughout Boston MetroWest & Central MA, providing high-quality remodeling, custom homes, and additions tailored to each homeowner’s needs.

Our team brings reliable craftsmanship, thoughtful design, and local expertise to every project, ensuring a smooth process and results that enhance both function and value. 

Our Service Area

  • Grafton

  • Westborough

  • Southborough

  • Northborough

  • Hopkinton

  • Sutton

  • Upton

  • Shrewsbury 
  • Boylston
  • Needham

  • Carlisle
  • Westford
  • Harvard
  • Sudbury
  • Berlin
  • Sturbridge
  • Oxford
  • Millbury
  • Newton
  • Natick
  • Wellesley
  • Holliston
  • Stow 

Gilmore Building Company is a proud member of the following organizations: