About Us
 Hi, my name is Gary Harstad and I am President of
GD Construction Inc.   
dba Comet Air Duct Cleaning
I'd like to tell you a little about Comet Air Duct Cleaning and how we originated.
Hi, my name is Gary Harstad and I am President of GD Construction Inc.  I have been a general contractor for over 30 years building homes from the footings to the shingles, and everything in between. I do know a thing or two about the construction industry.

In the early 90s, I started a Custom Cabinet Shop called Gold Dust Collection.  Here I built furniture and built custom kitchen and bath cabinets in and around the Billings area. If you would like to view my work go here:
GD Construction on Facebook.

Later I Incorporated and started GD Construction Inc.  (the GD stands for Gary and Debbie, my wife.) We started working with many of the box stores in Billings and have been doing kitchen and bath cabinet installations and remodels in new and existing homes. In the remodeling process of tearing out the old and installing new cabinets, we almost always come upon heat vents that come up under cabinets. It's what we would see in those heat ducts that prompted us into the air vent cleaning service. The dust, dirt, sheetrock dust, insulation and yes, the unthinkable that we would see in those air ducts was not very pretty. I'm quite sure in most homes it really is a dirty little secret in there, and if people knew, I'm certain they would want to do something about it.

My Grandson worked with me for most of his life and he was just starting a Double Major in Business at MSUB, so I asked him if he wanted to start a business, so we did and started Comet Air Duct Cleaning Inc.

We did a lot of research and found RamAir to be the safest and most effective duct cleaning system out there. With my many years in the construction industry, I knew the 3 major factors in cleaning heating and cooling vent systems would be:

Getting deep into the system. We have a Teflon ball with a series of holes that shoots the air out the back. With our system, the actual pressure we use for cleaning also propels us deep into the vent system with very little effort and time. I knew right away that we would be able to do a job much faster and better than any of our competitors and this would make us very hard to compete against.

#2- Getting the debris out. It’s one thing to get into a system, but another directing the debris out without making a mess. Comet uses a clear dome about 23” long 10” deep and 8” high with two holes on the top. One is for the pressure hose and the other for the vacuum.  The dome sits over the vent, with 200 lbs. of pressure we go deep into the system. We wait for the pressure to build back up and we begin coming out with all that pressure shooting back to us. As it is coming out all the dust and debris is going into the dome and the vacuum takes it out. You, the customer, can actually see just what is coming out of the vent and this is what we at Comet call the WOW FACTOR because you can actually see how effective Comet Air Duct Cleaning is at removing the dust and debris.  

#3 With newer homes and commercial buildings now using flex duct systems, with a brush system it is very easy to permanently ruin a duct system. Just by having a loose item such as a screw in the duct could tear it to pieces with the brush system. I couldn't imagine cleaning them any other way than with the Comet Air Duct Cleaning System.  

One of the first jobs Comet did was for a Sportscaster on a TV news station. When he came to the door, the first thing he said was “I personally think this is a total waste of money, but if this will make my wife happy, come in.” When we had everything set up and ready to begin cleaning, he was at the dining room table working on his laptop and I asked him and his wife if they would like to watch. As they were both standing right there Trei began the cleaning, and instantly you could see the debris going into the dome. I could see the expression on their faces as their jaws hit the floor. Both were shocked as they saw what was coming out. He instantly became a believer in Comet Air Duct Cleaning. This is the WOW FACTOR because seeing is believing.


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 call:  406 321 1504