• 800-378-3650

Welcome to Riverhead Building Supply

Home improvement professionals and homeowners look to us for a broad range of building supply products and specialty services. Providing the highest quality products and customer service is our main objective.

Find Marvin Windows and Doors at Riverhead Building Supply. Marvin is an industry leader in product innovation and energy efficiency, offering the most extensive window and door options. Experience Marvin's expert craftsmanship and superior materials for yourself. Visit one of our convenient locations on Long Island and speak with a design expert. Our consultative approach simplifies the selection process, enabling our customers to select the products and features needed to make each project as unique as they are.

GET STARTED NOW

All fields with an (*) are required.

Customer Form

Read This Guide Before You Replace Your Windows

If you're shopping for replacement windows or patio doors, it's easy to become overwhelmed by all the decisions you have to make. It doesn't have to be any longer.

Quite Possibly the Perfect Building Material
Quite Possibly the Perfect Building Material

Ultrex® pultruded fiberglass is the unsurpassed leader for lasting performance, strength and beauty. It is specifically designed to withstand the rigors of time and our harshest climates, while providing long-lasting aesthetics with clean lines and bold colors. Eight times stronger than vinyl, Ultrex products feature a superior finish that resists fading, dings and scratches.

Ultrex is available exclusively through the Marvin Family of Products. So you can rest assured that whether you are replacing your windows and doors, or building new construction, your home will look beautiful now and in the future.

The advantages of working with a Marvin Dealer

Whether you're building a new home, remodeling or making home improvements, we understand that choosing windows and doors can be a big decision. Our Marvin experts will walk you through the options - including energy-efficient glazing, hardware finishes, clad colors and other design features. We'll be there to answer your questions and help you make the right choices for your project.

20+ Years of Residential Remodeling and Replacement Experience

Every remodeling project has its own unique requirements and Integrity is equipped to meet those challenges. Two distinctive series, All Ultrex® and Wood-Ultrex®, provide an abundance of sizing, performance, and configuration capabilities to meet your needs. The Ultrex material pioneered by Marvin Windows and Doors, combines proprietary pultruded fiberglass and finish technologies that deliver proven energy efficiency and sustainable performance advantages. Our experts can guide you through even the toughest projects.

Tradition that never goes out of style

The double hung window has been a prominent feature in American architecture for centuries. At Marvin® Windows and Doors, it is part of our heritage of providing industry-leading products, and quality windows and doors for the American home. We are proud to make an American classic, handcrafted in America. With advancements in engineering the Marvin Ultimate Double Hung window now integrates a classic look with state-of-the-art durability, versatility and ease of use. Smooth operation, tilt-in convenience and extensive size, shape, and finish options make this the perfect window for remodeling, replacement, historic renovation or new construction projects.

Wide Open Possibilities

There's a magnificent vista on the horizon. You want to knock down a wall to turn an ordinary room into an extraordinary one and redefine your family room to include indoor and outdoor living spaces. And after all that, you don't want anything to stand between you and your view. That's why Marvin designed a line of Scenic Doors. The Ultimate Lift and Slide and Bi-Fold doors are available in stunningly large sizes and numerous panel configurations, they allow for a seamless transition from the exterior to the interior of your home. Marvin's industry-exclusive hardware virtually disappears, giving you an incredibly clean and unobstructed view with simple, effortless operation.