Our window and door showroom is currently under construction – check back soon or visit our Riverhead location at 1093 Pulaski St.

Window & door showroom

74500 Main Road, Suite 1, Greenport, NY 11944

 631-996-3250
 631-996-3199

Hours
Monday – Friday: 8:00 am – 4:00 pm
Saturday: 8:00 am – 1:00 pm
Sunday: closed

Explore all services at this location
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Riverhead Building Supply in Greenport is conveniently located at 74500 Main Road (Route 25) in Greenport.

Visit our Riverhead window and door showroom to explore top brands including Marvin, Andersen, TruStile, Therma-Tru, and more. Try out large-format windows and doors - such as bi-fold and multi-slide styles—that create seamless transitions between indoor and outdoor living spaces.

Stop by for your everyday hardware needs from hoses to power tools. Homeowners welcome!

Featured window and door products

ANDERSEN®
WINDOWS AND
DOORS 400 SERIES,
A SERIES

Quality and performance you can trust.

MARVIN® WINDOWS
AND DOORS

Windows and doors built for how you live.

THERMATRU DOORS

Where home begins.

TRUSTILE DOORS

Design that moves you.

INTERIOR & EXTERIOR
DOORS

Interior and exterior doors for any project from stock to fully custom.

RBS Pre-Hung Doors

Let us be your Master Carpenter.

Services

  • Delivery service
  • Window and door displays
  • Color and wood species samples
  • Window and door hardware options
  • Brand literature
Learn more about our services

Window & door repair and installation

  • Andersen® service & repair
  • Andersen® installed sales
  • Marvin service & repair
  • Marvin installed sales
  • Storm & screen door installation
  • Window & Door installation and replacements
  • Lift & slide ‘big door’ installation
  • Bilco® basement door installation
  • Screen enclosure installation
  • Garage Doors parts and installation

Connect with a millwork specialist

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