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So you think duct cleaning is going to help?

Now that another heating season is here, it seems the airwaves of both Radio and TV are filled with companies selling their duct cleaning services.

As counter-intuitive as it might seem, most duct cleaning is not only unnecessary but can make indoor air quality worse.

There are a few reasons when duct cleaning might be advised, but most of these are caused by circumstances that do not amount to everyday use of the duct system.  For example Ductwork that has been flooded, contaminated with toxic materials, infested with rodents, or coated with nicotine from smoking, might benefit from cleaning.  In these instances however I would recommend replacement—not cleaning.

Ductwork that has not been properly protected during remodeling or new construction might benefit from cleaning as well.

Generally speaking with normal use of the system, and proper installation and maintenance of the filtration system, duct cleaning should not be “routine” and is typically an unnecessary expense.  Cleaning ducts can remove the larger debris, leaving the smaller debris to be blown around in the ductwork and back into the living environment.  There are ways to clean the ducts without this happening but it is not cheap.  Certainly not the $199.99 advertized on TV.

Here is what the EPA has to say about duct cleaning:

Duct cleaning has never been shown to actually prevent health problems. Neither do studies conclusively demonstrate that particle (e.g., dust) levels in homes increase because of dirty air ducts. This is because much of the dirt in air ducts adheres to duct surfaces and does not necessarily enter the living space. It is important to keep in mind that dirty air ducts are only one of many possible sources of particles that are present in homes. Pollutants that enter the home both from outdoors and indoor activities such as cooking, cleaning, smoking, or just moving around can cause greater exposure to contaminants than dirty air ducts. Moreover, there is no evidence that a light amount of household dust or other particulate matter in air ducts poses any risk to your health. (The American Lung Association concurs with this assessment as well.)

Dust in the ductwork actually acts as a filter to assist in cleaning the air.

One reason to clean the ducts, which is almost never discussed, is to improve air flow and thus system efficiency.  This is not discussed because it would take EXTREME amounts of dust in the ductwork to affect efficiency greatly.  Given the benefits of some amount of dust in the ductwork, one could argue that any perceived loss of efficiency is offset by the Indoor Air Quality benefits.

One can also argue that brand-spanking-new-clean ducts allows for more particulate to be in the air because the ductwork is not filtering it out.

It is imperative that when, and if, you have your ducts cleaned, that it be verified that the service provider will take the necessary steps to protect the inhabitants from exposure to dislodged particulate as well as to the chemicals used in the cleaning process. 

If HEPA filtration was not used, if respirators were not used, if all supply and return registers were not removed or if you were allowed to remain in the home during the process, you might very well ask what you have really spent your money on and what will be the affect on your home’s indoor air quality—and you.


For more information see Duct Cleaning for Quackers  


Charles Buell, Real Estate Inspections in Seattle

 

 

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Seattle Home Inspector

 

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Comment balloon 42 commentsCharles Buell • November 17 2013 07:03AM

Comments

Hi Charles - Thanks for that explanation - it makes a lot of sense. I've heard many complaints from clients that these services were ripoffs or scams, but never really thought much about the reason for doing it to begin with.

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Posted by Dick Greenberg, Northern Colorado Residential Real Estate (New Paradigm Partners LLC) almost 5 years ago

I've always thought that duct cleaning could help eliminate pervasive odors often encountered in properties for sale or rent, such as the stink of cigarette smoking. Thanks for setting me straight, Charles.

Posted by Elva Branson-Lee, CDPE - Atlanta Real Estate & Short Sale Agent (Solid Source Realty GA) almost 5 years ago

Charles, good report. I might add that in addition to all you mentioned, when the flexible double walled plastic duct work is disturbed by the physical cleaning, if the inner wall is punctured, this can lead to condensation and eventually mold that will permeate the air breathed by the occupants. I have seen this occur often here in Florida. The result is the $199 duct cleaning can suddenly become a very expensive fix with the need to the replacement of duct work.

Posted by Sandy Padula and Norm Padula, JD, GRI, Presence, Persistence & Perseverance (Realty National) almost 5 years ago

Dick, there is for sure the whole scam and rip-off side of the problem as well.  Usually those are involved with selling you other expensive, unnecessary stuff--on top of the cheapo "cleaning."

Elva, there are contamination reasons to clean ductwork but many times those would better benefit from replacement.

 

 

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) almost 5 years ago

Norman, yes---that kind of ductwork is even more problematic when it comes to cleaning.  How exactly is one to drag or push cleaning equipment through them and not do damage?

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) almost 5 years ago

I think the money would be better spent cleaning the dryer exhaust vents which usually get dirty with heavy use.

Posted by Geoff ONeill (John L. Scott Medford) almost 5 years ago

Flexible ducts are cleaned by vibration, not brushing, so no damage results.  If, that is, the company has that ability!

This would be one reason for the very good filter used at the system.  There are two philosophies there - I subscribe to the high-filtration one, and wash my filter monthly.

Indoor air quality is probably more affected by opening our windows!

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) almost 5 years ago

Says he, with a knowing smile and a twinkle in his eye...

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) almost 5 years ago

I've always thought that blowing all that stuff around could be bad for your health!

Posted by Marc McMaster, Putting my clients before myself (RE/MAX Centre Realty) almost 5 years ago

Years ago, we were living in a basement while finishing a house.  The cats liked playing inthe vents.  They certainly kept them open if not cleaner.

Posted by Dwight Puntigan, Dwight Puntigan (DRP Realty, LLC) almost 5 years ago

Thank you - I have clients that are being pushed to do this by the parental units and I had heard it's not necessary, but didn't have any material to give them.  Now I do!

Posted by Joetta Fort, Independent Broker, Homes Denver to Boulder (The DiGiorgio Group) almost 5 years ago

Well, that is news.  I had assumed that cleaning the air ducts would always be a good thing. 

Posted by Virginia Hepp - Mesquite NV REALTOR, Mesquite NV Homes and Neighborhoods - Search MLS (ERA - Mesquite NV Homes For Sale) almost 5 years ago
Having proper air filters and changing them is where you should spend your money.
Posted by David Popoff, Realtor®,SRS, Green ~ Fairfield County, Ct (DMK Real Estate ) almost 5 years ago

I always thought it was to improve the efficiency, but I guess it makes sense that they'd have to be really really clogged up for that to happen.

I think I mentioned in one of your other posts that I was supposed to have my ducts cleaned on Friday. Turns out they couldn't do it because of how the system is set up and what their process was. But I did invest in an electrostatic filter because I go through my regular ones too quickly.

Posted by Suzanne Otto, Your Montgomery County PA home stager (Six Twenty Designs) almost 5 years ago

Well, that's interesting.  I'll bet that there are a lot of unnecessary and potentially unhealthy duct cleaning jobs performed. 

Posted by Kat Palmiotti, The House Kat (Grand Lux Realty, 914-419-0270, kat@thehousekat.com) almost 5 years ago

Not a fan of the duct cleaning process, especially on flex type duct work!

Posted by Fred Hernden, CMI, Albuquerque area Master Inspector (Superior Home Inspections - Greater Albuquerque Area) almost 5 years ago

Geoff and I would second that--and they aren't even included in those estimates for duct cleaning that you get.

Jay, I don't believe that flexible duct buried under 12 inches of cellulose fiber insulation can be vibrated at all.

Marc, and it seems it is

Dwight, that sounds a bit like putting the cat on a mop clip and dusting the house with it

Joetta, now you do---gotta love the parental units

Virginia, I wish it was---because it sounds so logical

David, absolutely

Suzanne, I have an electrostatic filter too.  Just remember they need to be cleaned really often too---and they are not really very easy to clean if you do a good job.  They are easier if you do it more often however.  There effectiveness drops way off as soon as you start to blacken the plates.

Kat, tons of them

Fred, for sure.  The metal ducts are one thing but with the flex ducts it is even worse.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) almost 5 years ago

Charles - I agree with you and really don't recommend the duct cleaning unless there has been smoking in the house.

Posted by AJ Heidmann ~ CRS, YOUR Alexandria & Arlington, VA Real Estate Expert (McEnearney Associates, Inc.) almost 5 years ago

I agree with you. Think it is mostly a rip off. Think I will just continue to replace the filter regularly

Posted by Bill Reddington, Destin Florida Real Estate (Re/max Southern Realty) almost 5 years ago

AJ, and actually cleaning the nicotine off the insides of ductwork is  probably not as practical as replacement of the ductwork.  More hidden costs of smoking.

Bill, a good filter, maintained and properly fitted to prevent the by-pass of air is a big component of maintaining indoor air quality

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) almost 5 years ago

This is the first time I've seen in writing why this should not be done.  There are a lot of firms here that do it, particularly with our long, cold winters.  Thank you for the information!

Posted by Margaret Goss, Chicago's North Shore & Winnetka Real Estate (Baird & Warner Real Estate) almost 5 years ago

Perfect timing.  We just completed a remodel on our personal residence and were contemplating cleaning the ducts or just replacing them as we see physical dust coming out of the ducts. After reading this I think it is better to pop for the full replacement of the ducts.  Thanks.

Posted by Jay & Michelle Lieberman, Creating Calm in the Buying and Selling Chaos (Keller Williams World Class) almost 5 years ago
Hi Charles, This is terrific information. The best way to filter and keep the vents clean is a built in air filtering system. Great for people with allergies or that have pets.
Posted by William Johnson, San Diego Real Estate Voice, GRI CRS e-Pro CDPE (RE/MAX Associates) almost 5 years ago

Charles:  Thank you for this post.  I have a referral partner that cleans duct work ... and he has been trying to talk me into having him come into our home to clean the ducts for a couple of years now.  I've not been convinced that this was something we needed to do, given our home is only about 10 years old.  Your post answered many questions I had ... thanks again!

Gene

Posted by Gene Mundt, IL/WI Mortgage Originator - FHA/VA/Conv/Jumbo/Portfolio/Refi, 708.921.6331 - 40+ yrs experience (NMLS #216987, IL Lic. 031.0006220, WI Licensed. APMC NMLS #175656) almost 5 years ago

I really appreciate the clarification on cleaning ducts when & why and also what to ask if and when I decided to do that.  This makes a lot of sense and great to communicate to buyers and sellers.

Posted by Kelly Young, Colorado Springs Real Estate ~ 719-226-0126 (The Platinum Group Realtors) almost 5 years ago

Great post Charles. I used to always recommend duct cleanings, but then I wisened up. Sometimes the floor registers get really nasty, but anyone homeowner can clean those up.

Posted by Juan Jimenez, The Richmond Home Inspector (A House on a Rock Home Inspections LLC) almost 5 years ago

Charles:  I was wondering about duct cleaning as I started to receive a lot of literature in the mail.  I think you have said it all with this quote

It is imperative that when, and if, you have your ducts cleaned, that it be verified that the service provider will take the necessary steps to protect the inhabitants from exposure to dislodged particulate as well as to the chemicals used in the cleaning process. 
Posted by Joan Whitebook, Consumer Focused Real Estate Services (BHG The Masiello Group) almost 5 years ago

Margaret, I am afraid that the duct cleaning is mostly snake oil

Jay & Michelle, of course all ductwork should be properly protected (not used) during construction, and if they have been contaminated they should be properly cleaned or replaced as necessary

William, the better the filtration system the better for the ductwork and indoor air quality

Gene, glad you find the info useful

Kelly, sometimes it is difficult to tell when something is snake oil or really necessary

Juan, same here---always have to be willing to learn in this business

Joan, yes---that is pretty much it

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) almost 5 years ago

Charles, this is some great information! I never thought about it but assumed it would be beneficial. I'll be bookmarking this post.  Thanks

Posted by Tom White, Franklin Homes Realty LLC, Franklin TN (Franklin Homes Realty LLC (615) 495-0752 or www.FranklinHomesRealty.com) almost 5 years ago

This is the first time I have heard that cleaning the ducts was a waste of time and yo made some very logical points.

Posted by Gerard Gilbers, Your Marketing Master (Higher Authority Markeing) almost 5 years ago

GOOD MORNING CHARLES ... well, I guess I was ripped off as I had my ducts cleaned for the first time earlier this year.  Sigh.

Posted by Gabrielle Kamahele Rhind, Broker/Owner (KGC Properties LLC, Tucson Property Management & Real Estate) almost 5 years ago

Tom, thanks

Gerard, it seems there are always two sides to every argument---especially when one finds there is a another side

Gabrielle, now you know for next time

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) almost 5 years ago

Charles, I have always thought that this duct cleaning scheme was a scam, but now you just confirmed it for me.

Posted by Morris Massre, Real Estate Instructor Broward County Florida almost 5 years ago

wow I would have never known that, Big Mahalo Thanks. Jeff

Posted by Jeffery Griffin, Broker Owner (Jeff Griffin LLC ) almost 5 years ago

Hi Charles,

Now that is some really dirty duct work. I bet they had a time cleaning all that.

Have a great day in Seattle.

Best, Clint McKie

Posted by Clint Mckie, Desert Sun Home, Comm. Inspection 1-575-706-5586 (Desert Sun Home, commercial Inspections) almost 5 years ago

Morris, certainly nowhere near as necessary as it is made to seem

Jeff, you are welcome

Clint, most likely

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) almost 5 years ago

I suspected as much and was always suspicious of the advertisements.  They were very effective in getting my tenants' attention and the tenant demanding that we clean the ducts.  We tried  to explain but those  ads are very effective. Your article goes a long ways in explaining why you should not have to clean the ducts.  Thanks.

Posted by Robert Fowler - 55CommunityGuide.com, 55+, Active Adult and Retirement Communities (President of Retirement Media Inc.) over 4 years ago

Once again, very helpful information Charles. I've developed allergies of some sort over the past year and many folks recommended air duct cleaning for our home. ( It's only 7 years old). Personally, I felt it was not the answer - and now I have your good advice as to why NOT to have them done.

Posted by Debb Janes EcoBroker and Bernie Stea JD, REALTORS® in Clark County, WA (ViewHomes of Clark County - Nature As Neighbors) over 4 years ago

Robert, there is nothing like a nervous tenant to compound the issue.  I see this with mold concerns as well.

Debb, the whole business of allergies will never be as simplistic as duct cleaning.  There are so many triggers and most people are not willing to look at the lifestyle changes that might be necessary to get to the root of the issue.  Many things in the environment "aggravate" conditions caused by totally different stressors.  I personally think diet plays a much bigger role than many of the things that people see as "causes."

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

Charles, I suspect you are right. I am going to explore the "food" triggers more this year.

Posted by Debb Janes EcoBroker and Bernie Stea JD, REALTORS® in Clark County, WA (ViewHomes of Clark County - Nature As Neighbors) over 4 years ago

Debb, you are entering a minefield---but can be well worth the exploration.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

Charles

I'm glad to see this reblog from Mimi Foster since I missed it the first go-round. It's not yet come up as an issue in any inspections, or with buyers requesting sellers take this on. No doubt at some point it may. There is some really useful and important information here! Thanks

Jeff

Posted by Jeff Dowler, CRS, The Southern California Relocation Dude - Carlsbad (Solutions Real Estate ) over 1 year ago

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