Hi Kathy - It's hard to say. Call your contractor first regarding the installation and if he needs assistance, call 1-800-Milgard. Your windows are covered for defects in materials and workmanship under the Full Lifetime Warranty. Thank you.
Whomever installed your windows is who you should start with.
I would think it was the contractor. I have been in my home sine 1995. My Milgard windows have been wonderful. The only faulure has been seals between the two pieces of glass. These will go bad with any window over time. Milgard has fixed these problems under their warantee. Excellent product and service.
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