All we do is replace windows & doors!

Installing high-quality replacement windows and patio doors improves your home’s beauty, minimize outside noise, and reduce heating and air conditioning bills.

Here’s why Cornerstone is different:

• Serving the South Bay since 1999
• Owner, Tony Szik, has over 40 years of contracting experience
• Fully licensed, bonded, and insured
• NO subcontractors – only Cornerstone employees
• Products are purchased directly from the manufacturer – no middlemen
• All windows & doors are custom manufactured to fit your home
• Cornerstone practices all health and safety precautions required by the CDC and local health departments.

We offer a large selection of high-performance products in the following categories:

• Vinyl Windows
• Fiberglass Windows
• Aluminum Windows
• Patio Doors – swinging & sliding
• Entry Doors
• French Doors

Our Commitment

Our commitment spans from everything to the value of our products to the craftsmanship of installation.

Transform your home with new windows! Call (310) 325-4700 or contact us today for a FREE in-home estimate.