Custom doors and windows in Long Island
and New England

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 for any project.

We partner 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, big-glass doors and 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.

Our doors & windows brands

Shop our stock door & window items

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