CALL/TEXT TO BOOK TODAY (720) 336-3777

Custom Ductwork in Boulder, CO

Welzig Heating and Air provides in-house sheet metal fabrication capabilities across a broad range of residential and light commercial applications. Creating precision fit, utilizing quality materials and customizing solutions to your specifications, we turn challenges into opportunities for greater efficiency, effectiveness and longevity. Get in touch with us at (720) 336-3777 to discuss your sheet metal project.

Family owned and operated since 1994, we’ve seen the difference of custom ductwork. The requirements of each home and business are unique. Through a design catered to optimize airflow, we achieve space-savings, greater heating/cooling capacity, maximum potential energy efficiency and more consistent indoor temperature. There’s far less chance of leaks, air quality contamination and stratification because of the integrity of our workmanship.

Contact Welzig Heating and Air for On-site Service

From ductwork fabrication to welding and on-site services, Welzig Heating and Air makes it easy to get the results you’re looking for. Our experience, expertise and resources prove invaluable, and we’re more than happy to offer guidance and recommendations. Let us take your plans from creating a vision to completion quickly and flawlessly. We are a trusted source of honesty and affordability in Boulder, Colorado.

Satisfied Customers
They Speak For Us

Bob came out to look at our swamp cooler and was remarkably helpful and professional. Not only did he give me a knowledgeable diagnosis, but he also taught me a lot in the process. We’ll be calling him for all future needs with our cooling system.


Dave Kaplan-Gomez and James Miltersen installed my new Tankless Water Heater. Both were polite and professional. Care was taken not to damage anything in my house which I really appreciated. I use Welzig for all my HVAC needs and highly recommend them.


Our 23-year-old A/C system ran out of “borrowed time” and became too difficult to continue maintaining. With great advice from Casey Welzig,, we replaced the old system with a Bryant Evolution A/C system. Max Loustaunau and Seth Bernhardt did an excellent job with removing the old system and installing the new one. Both of them are great to work with — very professional and very personable. We are really amazed at how much better the new system works!

Leave Us a Review!
Google Reviews
Angies List Reviews
Yelp Reviews
Facebook Reviews
Contact Us Now For A
Free Estimate