The story of Colorado Window & Siding Inc. (CWSI) started in 1983 when my parents, Bob and Diana Zimmermann, my brother Jason, and I moved from Michigan to Littleton, CO. With $2,000.00 in savings on arrival in Denver, Diana got employment with Martin Marietta, Bob started pounding the pavement door to door looking for customers for our new company, and my brother and I started school.
CWSI was started with the dream of providing customers with quality replacement windows and quality workmanship (finish carpenters) at a decent and honest price. We started out with an office in our home, while windows were delivered to a storage warehouse. Diana would do the paperwork of the business in the evenings, while Bob was out selling and arranging for installation. Eventually, Diana left Martin Marietta to work full-time with CWSI. The company grew to become the largest Weather Shield replacement window company West of the Mississippi. As we continued to grow, we relocated to an office warehouse on Prince St. in Littleton, then to a larger warehouse office on Dumont St. in Littleton.
As I grew older, I wanted to learn the window business. I sought employment as an Installer’s Helper (Gopher). My job was to fetch, carry, and rip out. Anything the Installer needed, I tried to do. My experience installing windows was gained on the job, taught by our professional installers. After 38 years in business, some of these original installers are still with us. Through my undergraduate and graduate studies, I realized my dream was to own and operate Colorado Window & Siding. I purchased the business in 2000 when my parents retired. They still help out in the business from time to time. I have a beautiful family of my own now, two sons and a daughter. One of my sons works in our office, so CWSI now has a third-generation employee. I am very proud to say that we are a family-owned and operated business serving Denver, Boulder, and the Colorado Front Range.
Delivering great customer experiences has been our focus since 1983. Our leadership team is involved in each and every project from start to finish to ensure the job is done with excellence and integrity. Over the years our motto has and will continue to stay the same.
Window, Door, and Siding Specialists
Wide Range of Products and Services
Honest, No-Pressure Consultation
Courteous, Clean, Professional Installers
100% Satisfaction Assurance
A+ Better Business Bureau Rating
Scott Zimmermann