OUR STORY
Founded by Mark Lounsbury, Lounsbury Built grew out of a simple conviction: most of what goes wrong in a custom home is decided before anyone breaks ground. What began as a passion for craftsmanship became a firm built around resolving the hard questions early — on paper, where they're still cheap to solve.
Our work lives at the intersection of design, construction, and close collaboration with the architects and homeowners we build for. With roots in high-end remodels and custom homes, we've developed a preconstruction-first process that trades surprises for certainty: real budgets while the design can still respond to them, buildability questions answered before the field, and a design that arrives at the site already defended.
Today we build in Marin County and beyond, on projects that reflect each client's vision — and on relationships with the architects, trade partners, and clients who bring us back. We've found that the best homes come from the least drama: a plan everyone believed in before the first cut.
MARK LOUNSBURY, OWNER
Mark Lounsbury is a 21-year veteran of the construction industry, starting as an apprentice under his father's general contracting business. After founding Lounsbury Built in 2018, he and his team have specialized in high-end custom homes and remodels in Marin County — building a reputation on complicated projects, where reading the set closely is the difference between a calm build and an expensive one.
His passion is in the relationships he develops with clients, guiding homeowners through the subtleties of the renovation process — from pre-planning and permitting through the final finish. His conviction is the one the firm is built on: the calmest, best-built projects are the ones resolved on paper first.
Our crew
The Lounsbury Built crew is a small, hand-picked group of trade partners and craftsmen who've earned their place through the work. Careful planning is what lets them do what they do — when the plan is resolved before they arrive, their skill goes into the build instead of into fixing surprises. Their attention to detail, respect for the schedule and budget, and pride in the finished result is what clients remember long after the last day on site.