Email: info@markinproducts.com

Tel: 888-229-3298

Showroom and Office:

475 36th St SE, Grand Rapids MI 49548

Company:

About Us

Who We Are

Careers

Service Locations:

Greater Grand Rapids Area

Ann Arbor

Lansing

Kalamazoo

Office Hours:

Monday - Friday: 9am to 5pm

Saturday - Sunday: Closed

All Major US Holidays: Closed

Proven Strength

The facts prove it. Ultrex fiberglass is eight times stronger than vinyl and three times stronger than vinyl/wood composites. It resists fading, chalking, peeling and cracking, giving you unparalleled strength and durability. We’re constantly testing Ultrex to prove it’s the toughest window material available.

WHY INTEGRITY FIBERGLASS WINDOWS AND DOORS?

Integrity windows and doors are made with Ultrex®, a pultruded fiberglass we’ve patented that outperforms and outlasts vinyl, roll-form aluminum and process to manufacture high-demand windows and doors that endure all elements without showing age or wear. 

Our values and work ethic are forged by the communities where we’re proud to live and work. When you choose Integrity windows and doors, you support a small-town, family-owned and pultrusion other fiberglass composites. We use Ultrex and our proprietary operatedcompany with deep roots in the community; some Marvin employees are fourth-generation, following the family tradition. We share profits with our employees; we support our communities; we treat our dealers and customers fairly and with respect. That’s Integrity.

Wood-Ultrex Windows and Doors

With a strong Ultrex Fiberglass exterior paired with a rich wood interior, our Wood-Ultrex has both strength and beauty.

All Ultrex Windows and Doors

Constructed with Ultrex from the inside out, our All Ultrex offers outstanding strength and durability.