Riverhead Building Supply is a Leading Source for Custom Doors and Windows

For custom doors and windows, look to Riverhead Building Supply. We offer our Long Island and New England customers the widest selections of quality doors and windows, providing you with the confidence and flexibility to help you or your clients make the best decisions.

We deal with manufacturers that can supply windows and doors in unique configurations for a completely custom look, or standard size units for quick turn-around. Choose from gliders, bows windows, double-hung windows, French doors, and much more. Our products are available with a wide range of glazing options, grille configurations and shapes, and we can tailor each item to your exact specifications. When your order arrives, we’ll deliver it to your job site free of charge.


We carry doors and windows from the following manufacturers:

*Long Island locations ONLY