Luxury Modern Home Builder Long Island NY


Keith Mazzei Interiors


We are not the typical interior design company— we are the epitome of elegance when it comes to building a custom home. Keith Mazzei Interiors is a trusted luxury home builder on Long Island NY with a decades-long track record. We are the top choice for distinctive sophistication and timeless elegance if you want to build or renovate a new home. Read on to understand what makes us the select option for the wise homeowner.

Custom Built Luxury Homes on Long Island

We help people on Long Island who don’t have the time, energy, or knowledge to build their homes. Keith Mazzei isn’t just another Long Island custom home builder. He is a seasoned professional interior designer who offers a full-service experience for luxury modern home building. He deals each step to building a custom home architectural design, construction, decorating, and finishing while controlling the budget.

Make It A Home You Love

We aim to be a high-end design-build interior designer dedicated to crafting custom homes that reflect our client’s desires and visions. As a Long Island luxury home builder, we streamline the creation of custom homes, providing an exceptional experience for our clients.

Our clients value a hands-off process — we seamlessly collaborate with architects, builders, engineers, and general contractors on Long Island, NY. As your advocate, Keith Mazzei Interiors ensures your needs and preferences are addressed throughout the project.

We are committed to delivering exceptional value, controlling costs, and providing financial peace of mind.

With a keen eye for both interior design and home design-build projects, we create elegant custom built luxury homes. From the initial concept to the final finishing touches, we pay meticulous attention to detail, ensuring each aspect aligns harmoniously with our clients’ lifestyles.

First One In & Last One Out

We strive to exceed expectations, creating homes that reflect your unique personality and enhance your daily lives. Our mission is to bring your dream home to life, encapsulating elegance, functionality, and timeless beauty in every space we design.

Long Island Interior Designer For Design-Build Projects

Our Story: Custom-built Luxury Homes

Keith Mazzei is the founder and leader of Keith Mazzei Interiors, a distinctive Long Island design and build custom home builder. His eye for creative design began very early and formally advanced when he graduated from the Metropolitan Institute of Interior Design in New York.

His love for ground-up construction is what distinguishes him from the crowd. He has over two decades of experience specializing in modern and traditional interior design styles and carefully learning every personal, lifestyle, and structural detail his clients require. His strength is delivering a timely and stunning project as the first person in and the last out.

Award Winning Long Island Luxury Home Builder in NY

Keith is a versatile designer and handles projects from Manhattan to Montauk. He takes pride in being in tune with the latest credentials, currently holding memberships to the American Society of Interior Designers and the IDS, and is a founding member of the Designers and Builders Alliance of Long Island.

about-keith-mazzei-Luxury Home Builder Long Island NY

It’s Your Home, Not Just an Investment

Keith knows the steps to building a custom home and understands that you should love a home. Whether updating the style while keeping the home’s antiquity or fusing modern conveniences with authentic Victorian or Tudor designs – we make it happen.

Luxury Home Builder Long Island NY

Freedom, Love, Connection, and Adventure in Home Design

Keith connects with his clients, becoming part of their family while creating a long-term relationship. Every new job is an adventure. Hiring Keith means avoiding cookie-cutter designs; it’s about your comfort in your home.

Relationships With Proven General Contractors on Long Island, NY

We have established relationships with tried and true general contractors on Long Island NY, for each expertise required to build a luxury home. We guarantee our team will be trustworthy, respectful, and honest.

Using our connections with Long Island general contractors avoids working with subpar professionals. Finding professionals requires much trial and error to get it right. Working with us allows you to avoid this cumbersome process.

Save Time and Money on Your Custom Built Luxury Home

Working with us only costs a small fraction of the total cost of your luxury home. We will save you endless nights of sleep and stress. Hiring us pays for itself, considering that doing it yourself will cost you extra time, money, and risk. Leave the stressful parts to us and unburden yourself.

Why Choose Us As Your Luxury Home Builder on Long Island NY?

Keith Mazzei Interiors is much more than a custom luxury home builder. We offer the complete experience of bringing your dream home to life. We provide valuable artistic, technical, financial, and emotional support and insights. We provide an experience that allows you to fully appreciate the personal process of bringing your luxury home on Long Island to life.

Services We Offer



Luxury Modern Home Builder On Long Island Keith Mazzei Long Island Home Foyer

Luxury Homes

Luxury Modern Home Builder On Long Island Keith Mazzei Commercial Office

Residential & Commercial

Our Extensive Portfolio of Work

Keith Mazzei Interiors handles unique interior design and high-end custom home projects on Long Island from Nassau County to Montauk.

Work With The Leading Luxury Home Builder on Long Island NY

At Keith Mazzei Interiors, we believe in turning dreams into reality. Contact us if you’re ready to build a luxury house that represents you. With our steps to building a custom home, you’ll find the process engaging and rewarding. Let’s make your dream come true.

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