With over 45 years of tradition, we give our clients a peace-of-mind in Dane County.




Our installation approach is based on the American Window and Door Institute’s Window Fitters Guild requirements. We have several certified installers on staff that participated in installation training and certification.

Successful window installation is dependent on utilizing the right application for each type of wall and window construction. Consumer Reports lists certification through the AWDI Approved Dealer program as a top priority for any consumer considering a window replacement project.

Find out more about AWDI



THEBCO Windows, Doors & Siding has won the Angie’s List’s Super Service Award in 2015. It’s our fourth year in the row. Thank to all our customers for all the outstanding reviews.

“Thebco was totally professional from the estimate through the installation,  Installers were timely, friendly and answered all questions about the process.” Monica – March 2015

” New Patio door, new living room, picture window & new window above kitchen sink. Also Oct 2002 – new bedroom windows & bathroom. They were professional cleaned up mess, & did an awesome job. On time.” Dennis and Susan – September 2014



BBB has determined that Thebco Windows, Doors and Siding meets BBB accreditation standards, which include a commitment to make a good faith effort to resolve any consumer complaints. BBB has determined that Thebco Windows, Doors and Siding meets BBB accreditation standards, which include a commitment to make a good faith effort to resolve any consumer complaints.

See our review on BBB Website



Our windows are designed to perform. We have carefully selected the best materials to make our windows stand above the competition in both aesthetics and the comfort and efficiency they bring to your home.

Many factors contribute to our windows being energy efficient, including installation, low-e technology and construction. While our competition may tout their awards, we have the numbers to back our products. In this section, you can see our performance ratings and details regarding installation and options and how they affect performance.



Lead is a toxic metal that was used for many years in products found in and around our homes. While no longer permitted in modern building materials, traces can be released into the environment by disturbing older installations, and can leach into drinking water from outdated plumbing fixtures and solder. It can also come from industrial sources and aviation fuel. Lead can cause a range of health effects, from behavioral problems and learning disabilities to seizures and death. Children six years old and under are most at risk.

If your home was built before 1978, there’s a good chance that lead paint can be found somewhere on the walls and woodwork of the exterior and interior. Thebco is committed to maintaining a safe environment for our workers and for you and your family. We adhere to stringent lead-safe practices with all of our home improvement services. If you have any questions concerning lead hazards please contact us today!

More information regarding the dangers of exposure to lead can be found at the EPA web site.


Thousands of people have chosen our products and we appreciate each and every one! As a bonus to our valued customers we offer a $100 check for every verified sale provided by your recommendation. If you’d like to participate please do not hesitate to contact us.

Customer Referral

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