Cornerstone uses only full-time employees — there are no subcontractors. That maintains a high level of quality control and a seamless installation process, and it is why most jobs are completed in one day.
In business since 1999, Cornerstone installs replacement windows, patio doors and entry doors from the industry’s premier companies: Simonton, Win-Dor, Milgard and Masonite. Readers of the Daily Breeze voted us a South Bay Favorite for Windows & Doors in 2020, 2021 and 2022.
Our installation system retrofits new windows and doors into your existing openings, so there is no construction mess and no repair work to schedule afterward. Protecting your home and furniture during installation is always a priority.
Every installer is a Cornerstone employee. No subcontractors, ever.
Most projects are completed in a single day.
Retrofit installation with no drywall or stucco damage.
Premier products with exceptional warranties. Ask for details.
Free consultations and free visual estimates, with a low-key approach — an informed homeowner makes the best decisions.
See windows and doors in person and talk with our team at our local showroom.
Visit our Torrance showroom or request a free, no-pressure estimate.
