Nestled in the heart of Nassau County’s North Shore, Mercer Built is reimagining what luxury living means, one custom home at a time. At the helm is Justin Marinoff, founder and multi-generation builder, whose passion for creativity and craftsmanship is transforming residential design across the region.
While Marinoff’s family roots trace back to restoration work—repairing fire- and flood-damaged properties—his own path took a decidedly more inventive turn.
“I’m a third-generation builder, but a first-generation custom builder,” Marinoff said. “The generations before me focused on restoration, but I pivoted about 15 years ago because I wanted to tap into more creative building.”
From Roslyn to the Gold Coast, Mercer Built homes are known for their originality. Whether constructing ground-up estates or executing high-end renovations, the company’s work never follows a template.
“Each house that we build, nothing is ever repeated or replicated,” Marinoff said. “Even our spec homes are built with the same care and detail as a custom home. We’re not trying to fit a million buyers—we’re creating something one-of-a-kind every time.”
Based in Roslyn, the company’s focus is primarily on northern Nassau County, with roughly a quarter of its projects extending out east to the Hamptons. The Mercer Built approach is firmly rooted in design-build principles, offering clients a more tailored and collaborative experience.
“People hear ‘custom builder’ and think cookie-cutter—like you’re going to open a photo album and pick Model A, B or C. That’s not us,” Marinoff said. “If a client sends me a photo of a hotel patio they love, I’ll scale and adapt that idea into something that fits their home and lifestyle perfectly.”
One of the most notable shifts Marinoff has observed in recent years is the rising demand for elevated outdoor living. What started as a design trend for second homes in the Hamptons has quickly moved westward to primary residences in Nassau County.
“Fifteen years ago, a patio and pool were enough,” he said. “Now, people want outdoor spaces that are destinations—covered porches with heaters, outdoor fireplaces, full-scale outdoor dining and living rooms.”
He attributes the change to the pandemic and a broader shift in wellness culture.
“People realized they need to love where they live,” he said. “Your backyard, if designed properly, is often a better investment than renovating your living room. We’re not just building patios anymore—we’re building real, usable living spaces outside.”
Mercer Built is also leading the charge in rethinking the lower levels of homes. What were once dark, underutilized basements are now wellness-focused retreats.
“We don’t call them basements—we call them lower levels because they’re built to the same standard as upstairs,” Marinoff said. “We’re putting in full gyms with cold plunges, saunas and steam rooms. These are serious health spaces, not just a room with gym flooring and a few dumbbells.”
The Mercer team’s philosophy extends into how they design for natural light and views—particularly for waterfront homes on the North Shore. Marinoff often works on properties out east with ocean or bay access and those lessons carry over.
“When we design a home, every window is intentional,” he said. “It’s not just about the view, but the quality of light it brings in. Scale and proportion are everything.”
The company’s process is highly collaborative, often starting with a vision and evolving through discussions with architects, designers and clients. The goal is always to create a result that’s not just beautiful, but livable.
“If you want to paint a wall red, there are a dozen guys who can do that,” Marinoff said. “But we aim to make it better than what the client thought was possible.”
Though the Mercer name is his own creation—distinct from his family’s earlier business—Marinoff carries forward the integrity and discipline he learned through years of hands-on experience. And while some builders might focus primarily on profit margins, he sees success through the lens of creativity.
“I’m in this to create beautiful, original homes, to ensure the product is right,” he said.
As for what’s next, Marinoff says the market is maturing—both in aesthetic and in intention.
“People on the North Shore are no longer just looking for square footage,” he said. “They’re looking for design. They want homes that feel thoughtful, where every space—inside or out—feels like it has a purpose.”
For homeowners looking to push the boundaries of traditional suburban living, Mercer Built is offering more than construction—it’s offering a new way to live.
Contact:
Mercer Built
1353 Old Northern Blvd, Lower Level
Roslyn, NY 11576
mercerbuilt.com
justin@mercerbuilt.com
