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MI® Windows and Doors

A flood of warm light. An effortless breeze. Slow Sunday afternoons. From morning to night, MI Windows and Doors offers beautiful, worry-free windows that help frame all of life’s little moments.

Our windows insulate as well as elevate, tirelessly working to seal out the elements and create homes that are protected, comfortable and quiet. From planning a project to everyday enjoyment, our promise is to help seamlessly connect customers to what matters most: the perfect windows for any space.

Please use our Contact Form to be connected with someone on our team discuss your project or to get further information.

Contact Form

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Why MI?

Why MI Should Be Your Trusted Manufacturer

Buying windows doesn’t have to be complicated. Our brands leverage superior experiences to seamlessly connect customers to the quality products they depend on to drive satisfaction for years to come.

With MI, you’ll experience beautiful, worry-free windows and patio doors to frame life’s little moments. Our exacting manufacturing process and the innovations we develop mean you get reliable, secure windows and doors that perform year after year. Plus, you’ll receive a level of service and quality others simply can’t match. All backed with a strong warranty for peace of mind.

Experience is Everything

Perfect windows begin and end with MI Windows and Doors. We equip you with everything you need to find the right windows and patio doors in the styles that fit your home.

Learn More at Why MI?

MI Windows and doors Product Selections

Product Selection

Learn about window and door styles, explore our series and browse features to help you find the perfect fit.

Find the right mood with a variety of window styles.

Explore Windows

Create seamless transitions from inside to outside.

Explore Patio Doors

Visit National Lumber's eShowroom to learn about their products, or contact National Lumber today to be connected with a Window & Door expert to discuss your specific project!

MI on eShowroom

Contact National Lumber

MI Windows and Doors porch showing sliding glass door and windows with black trim

Planning Your Project

Making informed purchasing decisions is vital for home improvement projects. MI is here to help. Click here or use the button below where you will find a variety of resources on the MI Windows and Doors website to help you start your project, including how to select your products, understand your options, and more.

Planning Your Project



At MI Windows and Doors, we are committed to providing our customers with high-quality, energy-efficient products. To do this, we proudly partner with ENERGY STAR® and work to continuously improve our products to meet its increasingly stringent requirements.


Satisfaction Guaranteed by MI Windows and Doors

Backed With Confidence

MI Windows and Doors strives to deliver exceptional customer experiences before, during, and after the purchase of our windows and doors. In this effort, we provide comprehensive window warranties and door warranties on all of the products we manufacture.

MI products are backed by an industry-leading Lifetime Limited warranty. Rest assured that if you have an issue with your windows or doors, we've got your back.

MI Warranty Information

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