Peace of Mind for MN Homeowners
Lifetime Protection and reliable coverage.
Warranty Overview
At Cornerstone Windows & Doors, we stand behind our workmanship and products. The comprehensive warranty is designed specifically for the extreme shifts of the Minnesota climate, ensuring your investment in performance and energy efficiency is protected for years to come. We offer a transparent, multi-layered guarantee that gives you total confidence in every installation.
Glass & Seals
Lifetime warranty
Comprehensive protection against seal failure and glass stress cracks, ensuring long-term thermal performance for Minnesota homes.
Download Full Warranty PDF
Frames & Hardware
Lifetime Warranty
Durability meets peace of mind. Our high-performance frames and hardware are guaranteed for as long as you own your home.
Installation
Guaranteed Workmanship
Quality installation is our cornerstone. We stand behind our artisanal craftsmanship with assured protection and care.
Easy Claim Process
For instructions for filing a warranty claim with Alside, click here.
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To file a claim with Alside, click here.
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Or contact us with any questions or concerns, and we would be happy to help!
Warranty FAQ
What does the lifetime warranty actually cover?
Our warranty covers manufacturing defects in the glass, frames, and hardware. Specifically, it protects against seal failure, warping, and hardware malfunction for as long as you own your home, ensuring lasting energy efficiency.
How do I file a warranty claim?
Filing a claim is simple. See above for details or contact us for assistance.
Is the warranty transferable if I sell my home?
Yes, our standard warranty is transferable to the next homeowner within a specific timeframe after installation. This adds significant value and peace of mind for potential buyers of your property.