MJM Masonry, Inc.

When a Massachusetts redditor asked in March 2026 who could fix a set of cement stairs, the answer came with a shortcut for judging quality: "Mark M from This Old House has a company. Might be an option, and likely done right." That company is MJM Masonry of Arlington, and the television connection is the through-line of everything written about it. Mark McCullough has run MJM since 1992 — the Better Business Bureau records the same incorporation year and lists him as president of a two-employee corporation, though it declines to grade the business at all, saying it has insufficient information. The work splits between the domestic and the structural: chimneys, patios, stairwells and retaining walls on one side; elevator shafts and brick veneers on the other. It turns up in trade press as a named masonry subcontractor, including on the Cotting School campus centre addition in 2022, and on a 2014 Associated Builders and Contractors safety-recognition list. McCullough also speaks publicly about the trade's bad actors. Quoted by NBC Boston in 2023 on a Malden home-improvement scam, his advice was blunt: if someone starts one project and suddenly finds several more, that's a red flag. Two things to raise before hiring. SVEP Navigator publishes a federal OSHA inspection of MJM Masonry & Custom Construction Inc. — the company's longer registered name — opened 2010-11-05 at a Burlington address, which resulted in four citations and $14,700 in proposed penalties. And the licences the company lists on its own site (unrestricted building, home improvement, CDL trucking) are its own statements, not registry-verified. A reasonable call for chimney, stair, patio or retaining-wall work around Greater Boston, particularly if you want a mason with commercial experience. Ask about the licence numbers directly and get the scope in writing.