Contact Cornerstone Windows

Cornerstone Windows and Doors is open to service your window and door replacement needs!

Please call or email to schedule a free in-home estimate, or if you have questions.

Cornerstone practices all health and safety precautions required by the CDC and local health departments.

Stay healthy. Stay Safe.

Tony Szik-Owner, Cornerstone Windows

Our Showroom is Open by Appointment Only

  • Monday-Thursday: 9:00 a.m. – 2:00 p.m by appointment only.
  • Please no drop-ins. Masks required.
  • Friday & Saturday: By Appointment Only
  • Sunday: Closed
  • Cornerstone Windows has a *4 window minimum*

Our Showroom

Cornerstone transforms homes with our large selection of:

  • Windows: High quality vinyl and fiberglass replacement windows
  • Sliding and swinging patio doors
  • French Doors

Contact Us for a Free In-Home Estimate

At Cornerstone, our expert estimators, office personnel, and installers are committed to providing skilled and satisfying service. We feature competitive pricing on all of our highly crafted products. Increase the beauty, value, security and improve energy efficiency of your home with new windows & doors. Please submit your contact form for a free, in-home estimate. We’re also available on weekends by appointment only.

Location: 3545 Lomita Blvd, Unit A, Torrance, CA 90505

Cornerstone Windows Patio Doors - 3545 Lomita Blvd Unit A, Torrance, CA 90505 - Truck Fleet

    Tony Szik's Cornerstone Doors & Windows, Inc., Door Installation, Torrance, CA
    Cornerstone Windows & Patio Doors - 2021 Daily Breeze South Bay's Favorite Window Door Company
    Cornerstone Windows & Patio Doors - 2020 Daily Breeze South Bay's Favorite Window Door Company