The out-of-place five-story walk-up on the first block of Commonwealth Avenue is almost unrecognizable now. The 1864 row house at 18 Commonwealth Ave has been rebuilt as a single-family townhome, expected to hit the market this spring with an asking range of about $20 million to $25 million. The home now runs roughly 8,100 square feet across five elevator-served floors and features five bedrooms with en-suite baths, a garden-level au pair suite, a private roof deck with an outdoor kitchen and two off-street parking spaces. Developers say they replaced the original foundation pilings, reframed most of the interior and installed modern mechanicals in a multi-year overhaul aimed at restoring the facade to something close to its 19th-century look.
As first reported by Realtor.com on March 15, 2026, the project is being marketed by Joshua Stephens of Berkshire Hathaway HomeServices and Tracy Campion of Campion and Company. Listing materials and the marketing site lean into the glossy details, calling out marble finishes, custom millwork, smart-home technology and sprinkler systems all tucked into what is billed as a historically sympathetic interior.
According to Boston.com, developers Lourenco Carminati and Eagle Hill Capital bought the building in September 2024 for about $7.85 million, then went through the Back Bay Architectural Commission to secure approvals. Project documents filed with the city, including a presentation posted on Boston.gov, spell out the approved facade restoration, a rear addition and a gated driveway plan to accommodate the new parking setup.
Design and construction
Interior work was handled by Boston Modern Design and Amber Wilhelmina Design & Interiors, and the dedicated listing site at 18Commonwealth.com underscores the marble surfaces, custom millwork and integrated smart-home systems. The listing also touts a two-car garage plus two additional off-street spaces and an elevator that runs to all five floors, turning the former walk-up into something closer to a vertical suburban house.
Where it sits in Boston's luxury market
If the home lists in the advertised range, it would land near the top of Boston’s single-family market, brushing up against recent records such as a $22 million Beacon Hill townhouse sale in February 2026. Realtor.com reports that the developers briefly considered carving the building into condominiums, but ultimately opted for a single-family restoration in order to keep more in step with the historic character of Commonwealth Avenue.
Long history on Commonwealth Avenue
The house dates to 1864 and has already had several lives, including a stint as a lodging house in the 1940s before it was gutted into 11 apartments in 1952, according to neighborhood researchers. Back Bay Houses tracks the property’s chain of title and mid-century alterations, while reporting by Boston.com notes that earlier remodels stripped out much of the original interior. Developers and architects say the latest restoration is meant to recreate the original facade and plug the building back into the avenue's historic rhythm, even if the inside now reads as decidedly 21st century.
What’s next
Agents expect the home to formally hit the market around May, with interior finishes wrapping up and facade work following after winter delays. The official marketing site offers floor plans and contact information for the listing agents for buyers and brokers already eyeing one of Back Bay’s priciest new-old addresses.
