Is Duct Cleaning A Waste Of Money?

Your HVAC unit is one of the most expensive systems in your house and impacts your indoor air quality. I recently had to clean/replace a few vent covers on my air vents at work that looked really nasty. When I took the old ones off there was something black on the supply registers and up inside the duct. Hmmm. That’s not good.

Next step, I called an air duct cleaning service. Only $99 what a deal!

Why does this matter to you? I’m hoping that you will do one search before calling to get your ducts cleaned and find this article. You might learn a few things that could save you money. I wish I had done this research BEFORE having my air duct system cleaned.

How to determine if you have mold

You can pay to have a sample of the substance you find inside your ducts tested. You can buy mold tests on Amazon. These tests come with slides that you use to collect the samples. You mail the samples off to a lab for about $50. The tests can tell you what type of mold spores you have, if it’s mold at all. Not all molds are equal and even if your mold growth is black, it isn’t necessarily the “bad” kind.

I don’t recommend hiring a service to come in and evaluate the issue for you. This can get very expensive (greater than $500) and they usually have some kind of skin in the game. This means that they profit from finding something in your house.

Do People Need to Have Their Ducts Cleaned?

Your home’s air conditioner and heating system comes with a built in cleaning process. That’s what the air filters are for and that’s also why you need to change them on a regular basis. Much of the dust particles, dirt particles, pet hair, dust mites and particulate matter gets caught by your filters.

If you ask professional air duct cleaners if you REALLY need to have them cleaned they will say yes. Here’s the story they told me:

“Dust collects in your ducts over time. It’s not all at the end where the filter is. If you don’t clean the dust out, it builds on itself. If there is any moisture from humidity or a leak you can develop a mold problem.”

It sounds stupid when I say I asked the duct cleaning company, but of course that’s what they are going to say. They absolutely have a script. I was caught up in the fear of dirty ducts and seeing something black up in the vents.

After a little more research I learned that the EPA only recommends professional duct cleaning services if you have solid sheet metal ducts. Most houses don’t have this. You can tell which kind of duct you have if you look in your attic. If it looks like a giant slinky, it’s not the kind that is meant to be cleaned.

The bottom line is if your home has flexible duct work (the kind that looks like a big slinky) getting the ducts cleaned can actually cause damage. The flexible ducts aren’t made to withstand the negative pressure of a powerful vacuum.

What To Ask Before You Get Ducts Cleaned

Beware of companies offering to clean your ducts for $49 or $99. A lot of companies offer this but will then try to up-sell you on something more serious when they arrive. They will tell you this is “basic” or a “standard” cleaning and that you probably need more than that.

They might tell you that your duct system has soot or mold. In my case, there was a scary looking black substance inside the vents that extended up into the duct work. They tried to sell me an $800 cleaning, but then told me I really only needed to do a $300 disinfectant.

After reading more about how duct cleaning works you should make sure to do these two things:

Ask for before and after photos of the ducts so you get a visual inspection. There are Youtube videos like this that will convince you to do this.
Make sure that they seal your vents before they start running the suction machine. Otherwise it blows the dust out all of your vents. The company I used didn’t do this.

How Often Should You Get Your Ducts Cleaned?

You should be very weary of any company that tells you to clean your ducts once a year. You really only need to do it every three to five years unless you have had water damage or construction in your home.

And definitely think twice about doing it at all if you have flexible duct work. You could do damage to the ducts.

What is Duct Sealing?

Companies that do duct cleaning can also seal your ducts. What does that do for you? In theory it closes up small holes in your ducts and improves the systems energy efficiency and may lower your energy costs. There are pro and con arguments as to whether this actually improves the efficiency of your hvac system and provides measurable benefits. Do your research. In short, home owners beware.