Family Owned Since 1983
A Dream Come True
The story behind Colorado Window & Siding, Inc.
Where It All Started
From a $2,000 dream to a Front Range tradition
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.
1983
Founded
$2,000
Starting Investment
3
Generations
A+
BBB Rating
Building a Legacy
Three generations of craftsmanship
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.
We would be honored to work with you. For an honest, no pressure, and free quote, please call or email us today.
Why Families Trust Us
The CWSI Difference
Window, Door, and Siding Specialists
Decades of focused expertise on the products that protect and beautify Colorado homes.
Wide Range of Products and Services
Access to over 20 leading manufacturers means the right fit for every style and budget.
Honest, No-Pressure Consultation
We listen first, recommend second, and never push a product you don't need.
Courteous, Clean, Professional Installers
Many of our craftsmen have been with us for decades — and it shows in every detail.
100% Satisfaction Assurance
Our leadership team is involved from start to finish to ensure excellence and integrity.
A+ Better Business Bureau Rating
We've held an A+ rating with the BBB since grade ratings were introduced.
"Our motto has and will continue to stay the same."
— Scott Zimmermann
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