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.

To protect customers and employees, we’re practicing all health and safety precautions required by the CDC and local health departments, including: employee temperature monitoring, social distancing, masks, gloves and sanitizing practices.

Stay healthy. Stay Safe.

Tony Szik-Owner, Cornerstone Windows

Our Showroom

Cornerstone transforms homes with our large selection of:

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

Our Showrooms are Open by Appointment Only

  • Our “Showroom on Wheels” comes to you!
  • Monday-Friday: 9:00 a.m. – 5:00 p.m by appointment only. Please no drop-ins.
  • Saturday: By appointment only
  • Sunday: Closed

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 - 2020 Daily Breeze South Bay's Favorite Window Door Company