OUR GUARANTEE Whether you are buying windows or patio doors for your own home, a client's home, or a commercial project, get real peace of mind. Get Milgard. Milgard stands behind every window and patio door we build. Our warranty promises we will repair or replace any defective window, door or skylight free of cost to the original homeowner. Parts and labor included. Our warranty ranges from 10 years for commercial applications to a Full Lifetime Warranty for homeowners. It's no hassles, no hidden costs, and no headaches.