Our Services

Ground Up New Construction

See a portfolio of what we have built recently.

Full Gut Remodel

See a portfolio of what we have remodeled recently.

Insurance Restorations

See some examples of insurance repairs big and small.

Roof Decks & Porches

Many examples of decks we build all year long.

Roofing, Siding, and Masonry

See examples of exterior work we have completed.

Boston’s Expert General Contractors, Providing The Highest Quality In Residential, Commercial & Specialty Work

Welcome to Abacus Builders

Serving South Boston and the South End, Abacus Builders and General Contractors is a Ground Up Development Specialists firm. Our experienced team specializes in multi family home building, general contracting, historical building repairs, and fine carpentry.

Our reputation is built on providing our clients with the highest quality of work at a reasonable price. You will not find a more skilled team of construction experts dedicated to excellence in the South End or throughout South Boston, MA.

Abacus Builders provides quality services such as New Construction, Full Gut Renovations, Fire Damage Restoration, Full Service General Contracting, Project Management, Planning and Permitting, Property Management, Architectural Design, Engineering, Roof Deck Specialists, and even landscaping services.

Contact the experts at Abacus for your next South End or South Boston project today.

Years Established

Completed Projects

We’ve Been Building For 17 Years

Our mission at Abacus Builders is to provide exceptional construction services to our customers. To continue expanding our company, giving our employee’s the opportunity to advance and grow. And, to remain a community-minded company and an asset to our local area through our continued work with neighborhood groups and organizations such as ONEin3, Harvest of Hope and the Notre Dame Education Center and the South Boston Collaborative Center.

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GoPro Timelapse

Click on the videos below to watch the expert team at Abacus working on past and present projects


Shawn BloomShawn Bloom
01:33 12 May 24
As knowledgeable as any GC I have ever worked with, terrific communication, very detailed oriented and their work is of the highest quality. Their proposals are always competitive. Happy to give a 5 star review. I will always recommend them to my clients.
Neil O'DonnellNeil O'Donnell
14:28 01 May 24
As new owners of an old condo on Beacon Hill, we hired Abacus to fix the mess of a prior unpermitted defective partial rebuild of a large elevated rear porch. The porch is nearly two stories off the ground. The rear of the building is accessible only by a tunnel. The workplace is small and constricted. Working with our engineer’s plans and their steel subcontractor, Abacus did an amazing job promptly and properly completing this complicated project. We greatly appreciate the communication, workmanship, and attention to detail from Mark, Lua, Gerald, Ryan and crew.
Molly PhomsoukhaMolly Phomsoukha
13:43 25 Apr 24
Exceptional experience with Abacus! They came in after another contractor abandoned our full gut renovation in the South End. I couldn’t be more impressed with the level of professionalism and expertise they demonstrated throughout the entire process. From the initial consultation, to the completion of the project, Mark and his team were not only knowledgeable in their field, but also incredibly approachable and patient. Their dedication to delivering high-quality results while maintaining reasonable rates was truly commendable. I highly recommend them to anyone in need of construction services and I look forward to the opportunity to work with them again in the future.
Samson LewisSamson Lewis
19:17 07 Apr 24
Abacus did a project with us last summer, completely redoing our roof and roof deck in Boston's South End. They were extremely supportive during the at times confusing city submission and approval processes, and the end product was excellent. High quality work all around, clear communication, good value compared to competitors, and a shorter project than others had scoped for us. We really appreciate the work!
Susan AthaSusan Atha
13:06 16 Mar 24
Honest, professional, and fairly priced owner Nick Cary and his team will give you their best making your property value soar.
Dean ToulanDean Toulan
20:12 14 Feb 24
The team was at my condo daily building the roof deck was awesome. Can't say enough positive things about the crew. However, Abacus gave the ironworkers the wrong plans and they built a spiral staircase for my roof deck and installed it on the wrong side of my house. Abacus refused to take responsibility and when I wanted it moved to the correct side from the original plan I received the "dog at my homework" routine and gave me a rundown of excuses. Mark never bothered to come down to actually see the project once but somehow tried to place blame on me as if I'm in construction. He was rude and unprofessional. Never completed the project. I got the permit from the city that it was approved, even though it doesn't have a gate which the city requires. Don't work with this company.