Do you wonder why your house gets dusty so fast?

Do you have something like this in your attic?

Do you feel like your house is always dusty, in spite of how much you vacuum and clean? Have you tried all the tricks – HEPA vacuum cleaners, air cleaners, taking your shoes off before coming in the house, washing the dog…. all to no avail?

Chances are good that you’re being plagued by a leaky duct and air handling system.

When you have leaks in your ducts (virtually all duct are leaky) dust from the attic gets sucked into the ducts and distributed throughout the house. Even if you have an excellent filtration system on your air handler, the dust can be sucked in from places that don’t get filtered, and blown into your home, usually leaving fine gray dust everywhere.

Before you call in a heating/cooling (HVAC) contractor, there are a few steps that you can take yourself.

Warning: working in an attic can be dangerous. Many attics don’t have proper floors. Numerous people have taken bad steps and fallen through the ceiling, often resulting in serious injury or death.

Assuming you are comfortable working in the attic and can safely access the duct work and air handling system, here are some things to check:

  1. Ensure that the air filter port is sealed air-tight.
    At least  10% of the systems I see look like the one in this picture. The air filter port is open and an over-sized filter is sticking out the side. Not only does this rob you of 20%-50% of your system’s efficiency(!) and cause the air to get extremely dry in the winter, but it sucks nasty, dusty attic air into the system where it is blown throughout the house. Fix this simple problem  (get the right sized filter and tape over the port) and you will see immediate energy savings and probably a much less dusty home.
  2. the duct "boot" has a big gap

    Check your air registers around your house
    Your home’s air registers should mostly be clean. If some are much dustier than others, this is a sign of leaks near that particular register. Sometimes it will be a leaky duct leading to it, other times it may be the register itself is poorly attached to the ceiling, providing a gap right into the attic. I’m always suspicious when I see a really dusty register.

  3. On a cold and windy day, turn off your forced air system (air conditioner, heat pump or furnace) and see if you can feel a cold breeze coming from any of the air registers in the house. The duct system is supposed to be completely sealed, so you should never feel really cold air blowing in. You might feel cool air drifting in due to the ducts being cold, which causes the cool air to “drop” out of the ducts. But if you can correlate cold air blowing in with wind outside, you’re sure to have leaks. The more of a breeze you feel, the closer you are to the leak.
  4. Poorly attached duct

    Look around the attic to see if any ducts are visibly detached or “askew”, particularly at registers and ducts that failed test #3 above.
    These can be hard to find, but sometimes it’s pretty obvious. All the ducts should be nearly and strongly attached at both ends – where it leaves the main trunk lines and where it feeds the ceiling registers or air returns.
    I’ve seen cases where the ducts have totally fallen off and are just lying on in the insulation.
    Note: special tools and adhesives are used  to connect ducts in a permanent fashion. Do not attempt to repair these problems with “duct tape”! – this tape will fail and you’ll be left with leaky ducts again. Instead, industrial strength zip-ties and tensioning tools are used along with a sealant called “mastic.”

  5. Sometimes problems are hidden in walls
    You might not be able to find any problems in the attic but the problem could still lie in your ducts. Many duct systems run through walls and hidden cavities in your home. It is even common  practice to use naked wall cavities without ducts! Contractors will just pick a wall, ceiling or floor cavity and run air through it. This horrible practice really shouldn’t be permitted because it causes so many problems.
    This type of problem you probably can’t find yourself. A trained infrared thermographer (often an energy auditor or building scientist) may be able to locate the problem, but sometimes it can be very difficult.
  6. Beware of Vermiculite
    Some older homes have Vermiculite insulation in the attic. These homes should not be tested using a blower door or duct blaster and you should not poke around in this material because it may contain asbestos. Not all Vermiculite contains asbestos, but this is definitely a case of “better safe than sorry.”

I started this post saying that you shouldn’t call in your HVAC contractor and I’ll finish it by saying the same thing. Many HVAC contractors are not trained to find these leaks. Think about it – who created these leaky ducts in the first place?

As a building science / energy consultant, I’m biased because I’m an independent consultant, and I recommend that you use someone who is also independent to diagnose your issues. They might fix them as well or they recommend a high-quality HVAC contractor whom they know to do good work. They will also have special equipment like a “blower door” and a “duct blaster” that allows them to quantify the leakiness of your ducts much more quickly and accurately than someone without these tools. In fact, without at least a blower door, it will be very difficult to even find many duct leaks.

Fixing duct leaks can help make your house much less dusty and it has the side effect of making it more comfortable and energy efficient. This is one of those things that you’ll wish you had done years ago because it can make your house more enjoyable to live in every day of the year.


“Why does house get dusty when heat on and not with ac on?”

Occasionally, weird things happen. If you’ve gotten this far, you know that the dust is usually sucked in and distributed by the duct system. If that’s so, then how does the above situation occur?

There one possibility that comes to mind – moisture.

During the summer, the cold coils in the air conditioner are covered with water – this is the summer moisture getting drawn out of the air. When the dusty air moves through the coils, much of this dust could be trapped by that water. This would lead to much less dust when the air conditioner runs than when the heat is on.

“Does an energy audit show why there is so much dust in the house?”

Someone else asked this question. The answer is “maybe.”

If the energy audit is a comprehensive review of your home, done by a competent technician, then yes, the audit should be able to show why your home is dusty. To make sure, you should tell your auditor that you’re having a dust problem and you’d like some help finding out why. If they look confused and don’t suggest issues like the ones mentioned in this post, you should probably find a different auditor!

“Why is the air so dry in the winter?”

What does dry air have to do with a dusty house? Possibly everything!

If your duct system is sucking dusty air in from the attic, it will also suck in the very cold, dry air from the attic. When that dry air enters your house, it sucks up the moisture from your home like sponge, resulting in very dry air. That’s why an uncomfortably dry home in winter is a giveaway that the home is very leaky.

Keep in mind that the dry outside air could be coming from anywhere. If you have leaky windows and doors and a drafty house, it’s also going to be uncomfortably dry. That said, nothing dries out a house faster in winter than a leaky duct system that’s sucking in cold, dry outdoor air.

115 thoughts on “Do you wonder why your house gets dusty so fast?

  1. Hello, happy I came across your blog… our home isn’t new.. built around 1996 or so (Florida)… we had a slight dust problem and had our AC company install 9-months ago an air scrubber and had at one point a UV light installed also, since the air scrubber install the amount of dust like particles is EVERYWHERE! Within minutes it’s piled back up on every single surface… it doesn’t look like typical dust like more like what I’ve read above and something other than just plain dust… we’ve called the company back out 3x now & were told it’s part of the cleaning out the ducts old stuff that has settled process & was told initially at the 3-month mark it would stop…. Second tech that came out said at the 6-month mark it would stop… & the worst he’s ever seen was longest 6-months & the home was very old! Aside from the obvious annoyance of constant daily cleaning/dusting/vacuuming … our allergies through the roof. PLEASE HELP! Who do we call at this point? What should we do? Also to add… the one previous tech said he searched the attic/ducts and doesn’t believe there to be any leaky ducts? He didn’t do the blaster test I’ve read about on here ..: any local companies you could also suggest to help us would be greatly appreciated too… the only suggestion our AC company had was to replace entire house duct system!

    • Since this only happened after they did the installation, the most likely cause is that they left some gaps in the ductwork connection between their unit and your HVAC. Do you have access to where the unit is? A visual inspection of the connections between that unit and your ductwork should show any gaps or places air could get in. If you didn’t have issues before, then their argument about it being cleaning out gunk in the ducts is bogus. A second opinion at this point could be very helpful. You might also look up “ indoor air quality” To see who might be available locally to check out your problem. The difficult part is that it is hard to tell who is good and who is just trying to sell equipment. Sometimes I contact local contractors to see who they recommend for work of this sort. They usually have the behind-the-scenes information on local contractors.

      • Wow! You’re quick lol Thanks so much for fast reply! Since not a newer home we did have a little dust issue … prior to the air scrubber install.. but nothing like the last 9-months & only seems to be getting worse. I’ll do some digging/research with who to call out … that’s what I was worried about, getting another run around from some bogus company trying to sell another product and miss the underlying problem! Yes we have visual to where the actual system is, but honestly neither of us know at this point what exactly it is we should be looking for … I’ll pass this along to my husband about the gap part as well. Greatly appreciate your speedy reply!

      • Honestly, the problems usually are very obvious. I have seen ductwork left sitting on the attic floor and covers for the filter left off so that dust from all around the area just gets sucked in and distributed around the house. They may have also used metal tape To seal things up without cleaning the metal. Often the metal is coated with oil so you can imagine how well that works!

  2. Hi! Thanks for this post. I know I’m answering a couple years later. I recently moved to a new house and have NEVER dealt with so much dust. Our house was build in 2001 and has blown insulation. We had two AC companies come out and they said the ducts are sealed (but they didn’t do a blow test). I vacuum every day and dust every day only to come back to more dust. It does look like dryer lint like you explained. I have an attic opening in our guest room that is just the ceiling set into some trim. Do you have any suggestions on how to seal that up? And we also have recessed lighting. How can we seal that to make sure no leakage is from there?

  3. So this is a really interesting article and informative. I’m a roofing contractor of some 30 years. I’ve been in construction more than 40 years with extensive experience in electrical and allthough this helps when I’m trying to figure out why an A/C won’t work; has not helped in figuring out my current problem.
    My A/C handler seems to be producing dryer lint and covering everthing in the entire home with it and I mean everything! The handler was in a mock closet (Florida home). I had air leaking from where the fiberglass duct flume attatches to the top of the handler. The air is then disbersed from the flume down a lower hallway ceiling to conceal the foil backed fiberglass duct. Water was leaking periodically from the bottom of the handler, where the return was. The past resident had actually put a bucket under the handler to collect the water. I got into the attic and noticed the duct had moisture on top periodically.
    When I first moved in I had an A/C guy come out and as you said: didn’t have a clue! He did notice that the coils where all covered and I mean covered with this dryer looking lint. He took them out, cleaned them and put them back. I then had the the ducts cleaned. The problem persisted and after many return trips out here and frustration on both of our parts; I called another A/C guy that I’ve worked with on roofs and he told me the duct was leaking.
    I removed all the duct, vents, flume, ripped out the lower hallway ceiling. I then moved the handler into the attic above the hall, put the return in the hallway ceiling and ran all new duct. I was able to spread the drops more efficiently throughout the home. Everything was new equipment except the handler. There was also mold in the mock closet on the drywall and had penatrated into the framing so ripped all this out also. I’ve bought air cleanig machines (that currently have this gray flake dust on them) and have been running them since completing this work 6 weeks ago. exception: drywall is up on the hallway ceiling, not finished and has some very small openings, but definitely air leaks from home into the attic (will close up tight this weekend).
    Currently I’m still experiencing the same issue with this gray lint.The dryer is in the garrage that is attached to the home and it vents out the rear block wall right behind it. I’ve pulled this out and cleaned what looks like the same stuff in the house under it. The attachment to the dryer and vent going through the wall are good. The outside wall louvers are damaged and I haven’t inspected the: through the wall part of the vent for leaks yet (this weekend’s project). The door into the house is 24″ wide and has a small opening under it of 1/8″. Other than what I found under the dryer (after years I’m sure of not being cleaned) and what appears to normal garage lint and dust.
    The home has an obsessive of amount of this flufy looking gray dryer lint and small flakes on everything (walls, blinds and I mean every nook and crany). The bathroom is the worse room because it’s the smallest. Most of the dust is gray flake that is on everthing. I wipe the bathroom porcelain fixtures yesterday and it’s already on them again (I did run the dryer yesterday). It definitely looks like dryer lint. I’m baffled as to how come and why so much of it? If it’s dryer lint, how is it getting all the way from a added on attached block garage and home with just a cubby hole pass through from garage to home in the attic?
    Remember how I started: I said it appears to be the handler is producing this. I moved the handler from a A/C mock closet, inside the air conditioned part of the home and into the hot Naples Florida attic (common here). A/C appears to be running perfectly since the move and temperture is already in the high 80’s here. I haven’t inspected the inside of the handler, but plan on to this weekend before I secure the drywall from anymore through the ceiling attic/home leaks. I tried to give you as much information as I could with hopes of you maybe having a solution. I’m an exceptional roofing contractor and with as much as I know still have trouble sometimes finding the culprit; so I understand that you may not know what’s going on. If you have any suggestions or can add any light to this troubling situation it would be much appreciated. Thank you, Dean Scharn

    • Wow, you gave it a real good try by redoing all the ductwork and moving the air handler. And it seems like you’ve trouble shooted most of what comes to mind.
      Does the house have blown in insulation anywhere? That can look just like dryer lint. It still wouldn’t explain how it’s getting distributed around the house, but it’s a clue.
      Also, you can try covering all the air supply registers with air filter material.

    • (Oops, didn’t mean to send yet)
      The filter material would catch the lint coming from the registers and give a big clue if the lint is coming out the registers and if so, which ones are worst, indicating which run has problems.
      Another thought – many homes use wall cavities to run air through without ducts in them. Is it possible that any of your runs are like this?

    • Hi Dean, I can’t tell you how bizarre it feels to be reading your comment, as it is literally almost an identical situation to what my husband and I have just spent the past 2 years dealing with in our home. It continues to confound us that there are almost zero articles, publications, or environmental impact studies available to the public on the internet that outline or discuss the issues of fiberglass (including rock-wool, blown-in) insulation. It’s in something like 95% of homes in the US–behind walls, in attics, & HVAC ducting–yet virtually all companies & services being advertised on the internet (or even talking about household air quality) fail to even mention the word “fiberglass.” The EPA regulates it (albeit too loosely, but to a degree) for commercial and industrial settings, but there is virtually no regulation for residential & spaces where people reside.

      • In our personal, direct, experience, air quality testing for fiberglass (separate from asbestos or general “dust”/mold testing) doesn’t even exist for consumers or homeowners wishing to discover the level of fine particulate matter in their household air. There is a website called & a new one that’s in the works called, that serve as the most comprehensive personal accounts we’ve been able to find, but aside from that, it’s been extremely disappointing (and alarming, frankly), that so little information (including medical research) exists for the general public when it comes to fiberglass–especially when it appears, at least in your case & ours, that all other sources of indoor air pollution have been explored, mitigated, and exhausted with the problem still remaining.

    • What type of work are you looking for? Tracking down dust problems?
      For those, I’d try a company that does duct pressure testing. These should be easy to find because NJ has required testing of new homes for a number of years.
      Put your town into a search for “duct pressure testing nj bpi certified”

  4. Hello,

    Thank you for posting all this useful information. I have lived in my house for four years now and get so frustrated with the dust. My house was built in 1962, the house has new windows, I added filters to the vent, but there is still dust all over my house, floors, kitchen, furniture… I had a duck cleaning company come give me an estimate to clean the ducks, and it was $1400 for a 1400 sqft house. But the ducks were didnt look dirty. I didn’t hire the company because I thought there must be another problem. So am not sure what to do? Based on your post it seems like I might have a leaky duck?

    • Have you checked those filters you added to the vents? If they’re dirty, then you can tell the system is circulating dirty air. If they’re clean then the dust must be coming from somewhere else.
      You could try a test. With the house all closed up (windows and doors closed), try turning on everything that blows air out of the house. That would be all the bath fans, range hood fan (if that vents outside) and your clothes dryer. Then check for drafts at all the vents. You shouldn’t feel anything. But if you do feel something at a vent, then there’s a leak. The more you feel drafts at the vent, the closer the leak is to that particular vent (in general).
      Dust can come from other places. For example, if there’s lots of foot traffic in and around the house from kids or dogs, that can bring a lot of dirt in. You’d probably notice this however. Dust can also get sucked in from places like recessed lights. If you have lots of recessed lights, it’s possible that dirty air is getting sucked through the lights.
      Those are a few ideas.

  5. Looking at your article for answers to my dust problem I have been having, I dont have any Duck system cause we have no furnace or central air, I do have a draft that comes in from outside up stairs and you can feel it come down the stair well. Could all my dust be from this draft? but the dust is every where, in the kitchen down stairs the living room. Seems really bad this year vs the previous years though which is kinda odd. We’ll wipe our surfaces down one day and next day or so and itll look like its been a few more days then it has. Thank you for any replies,

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  7. We live in Arizona in a house built in 1986. Yes it is dusty in Arizona but having lived here all my 70 years I have never seen any thing this bad. I have asked my neighbors about their dust issue. None of them have the problem like we have. The dust is in all our clothing drawers and closets. We continually vacuuming and dust. I rececently noticed that the inside of the windows are more dusty than the outside. Crazy right. My husband found an unusual issue in the duct work. The inside of the duct has insulation and there are nails poking up through the insulation. We have never seen anything like this before. Could this be our problem.

    • That seems strange. Did the dust problem start recently?
      I think your husband is on the right track. My guess is that your duct system is sucking in and distributing all that dust around the house.
      In all likelihood, the small nail holes are not the culprit. Instead, I would trace the ducts looking for bigger gaps between ducts and the main system. It might even be that one of the ducts has fallen off from where it’s mounted.
      If you have the air handler (blower) in the attic or in a dusty space, you should also check that to see if there’s places dust could be getting sucked in. Culprits are where the unit connects to the ductwork and the place where you put the air filter. Everything needs to be sealed up air-tight or dust will enter and get blown all around your home.

  8. Hi! Very informative article! Question… we just purchased a quad (split) level home with one zone air conditioning and baseboard hydronic hot water heat (powered by natural gas). We do not have the ac fan running just the heat and the house is terribly dusty. Any ideas on why this would be happening?

    • Even without running the fan, natural air currents could be circulating through the ductwork and picking up dust. A cheap and easy test of this is to get a roll of Glad Press-n-seal from the grocery store and use it to cover all your air conditioning vents during the winter. If the dust is coming in from the ductwork, then the house will be much less dusty and then you can track down the problem in the ductwork. If the dustiness persists, the test is useful because then you don’t have to waste time and money having the ducts inspected.
      In a house, natural air currents are from basement up to attic, so if you have a dusty basement or dirt crawl space under the house, natural air flow will bring dust into your living area. When you run the dryer, kitchen or bathroom fans, this will accelerate the process. Note that running these items would also pull dust in through the ductwork if that’s a problem.
      If you use my “Glad” trick, try turning on all the bath fans, kitchen vent fan and dryer then look at the sealed duct vents. You might notice that the plastic is pulled inward from the air pressure applied by the fans. With a tight duct system, you shouldn’t see this. You can also remove the plastic from a single vent and see if you can feel a lot of air coming in. You shouldn’t feel much if the ducts are tightly sealed. If not, you’ll be blasted by air, probably dusty air, when you try this test.

      • Thank you so much! We will follow the advice you have given and report back in a couple months. Also, I wonder if you could shed any light on why we have dark sooty shadowing on our walls? We can see the perfect outlines of the previous owner’s frames. The house was built in 1963 and has plaster walls. The had renovated the house in 1980 and I am guessing that is the last time it was painted. I am repainting now. The house has a fireplace which we have not used along with the gas boiler for our baseboard heat and water heater. The worst shadowing is on the ouside walls in our living room above the baseboard heaters (which run the length of both walls). I have also noticed very faint tan splotches all over these walls… and a greasy tan sticky stuff in kitchen on walls/cabinets. Could this be old cigarette smoke? I read that shadowing can happen with insulation problems on exterior walls… but every article I found references the shadows following wall studs which ours does not. Could this shadowing be another symptom of our dusty house? Thank you again for your help!

      • Regarding the sooty shadows – I ran across something exactly like this once – apparently the occupant regularly burned candles and oil lamps. I didn’t realize it but these generate microscopic soot that floats in the air and sticks to any surface, leading to this type of shadowing. it’s easily possible that the fireplace or cigarette smoke is responsible too.
        Colder, exterior walls are more prone to this effect because they’re colder, resulting in a slightly higher moisture content which traps the soot. your research is correct – usually it’s at the studs, but it doesn’t have to be. Especially if it’s been building up over years. it’s possible that some of it is trapped dust. That’s fairly easily tested – if it’s soot, it will be jet-black. Dust is usually grayish.
        As for the kitchen, that sounds like it’s from frying/sauteing food.

  9. Good Morning. We had the insulation completely ripped out of our house and replaced. Now our it is extremely uncomfortable. We have done everything from sealing all duct work we could seen. to using areo seal. We had had the attice insulation completely ripped out and replaced. and now The hard wood furniture is chipping, peeling, and fading all over our house. We had the connecting walls to garage insulated. The tools in our attached garage has rust all over them. We have paid a lot of money to have this fixed and now it worse. We live in the Philadelphia, PA area. I took infrared pictures and there are blue spots all over where the wall meets roof. I really just want to get it fixed somehow! I appreciate your help.

  10. I have a house in Orange, CA with awful brown silt that gets on everything. I can write my name on the walls behind doors. If I try to clean the carpet with water it turns into mud. Awful! This happens even without a working a/c system. I was going to have the ducts cleaned but it sounds from the comments here that is the wrong first step. Any suggestions?

    • That sounds bad. From what I’ve seen over the years, and experienced first-hand visiting the region, the droughts have lead to many dust issues for people. The problem is, with nice weather, you want to let fresh air into the house, but if that air is laden with fine particles, you’ve got a problem!
      Since it’s happening without the A/C running, the dust has to be coming in with the general air that’s naturally entering through windows, doors, cracks and so forth.
      You could look at the possibility of running the central A/C fan continuously with a good HEPA filter to see if that helps. That should provide some benefit as long as the A/C ductwork is relatively well sealed. Even if the A/C itself isn’t working but the blower part works, this circulation/filtering should eliminate some dust.
      You might also ask some of your neighbors to see if they’re having similar problems and if they how they have approached it.
      If all else fails, you might look for a local ‘indoor air quality” specialist. They should be able to test the dust to see what exactly it is, and recommend remediation methods.

  11. Hello, I have commented before and told you about our excessive dust. We have had an energy audit and also an hvac company come out and look at our problem. We had a blower door test done and it says our home leaks 1498 CFM or approx 66% of our indoor air every hour. The hvac company had our dust analyzed and it came back as dryer lint. We have scheduled to have the attic insulation removed, then spray foamed and new insulation put down. Also they are going to spray foam all attic and basement penetrations and spray more foam on the basement rim in addition they are going to put aeroseal in our ducts. The hvac company is proposing to add a fresh air intake to our hvac system and add a hepa system to our hvac unit. I am wondering if it is dryer lint and our dryer sits on an outside wall and directly vents outside, how in the heck are we getting dryer lint all over our house and will we be spending a small fortune and not solve the real problem? I will send you a photo of how our dryer vents outside.

    • Thank you so much for the follow-up. Dryer lint! I should have thought of that.
      There’s got to be a leak in the dryer duct or the connection isn’t bad. You would think that there’s be lots of lint near the machine. Have you been able to remove the dryer and inspect it? I would think it should be fairly obvious.
      The other possibility is that there connection through the wall is bad.

      • We recently purchased a new dryer and had a new vent installed and the dust level is still the same. We noticed there is an attic air vent right about where the dryer vent comes out of the house. It isn’t plugged as we thought it should be, but could the dryer lint be going up into the attic and back into our house? Another strange thing is that our furnace filter never looks dirty and we keep changing it monthly. I sent photos to your facebook messenger. Also we took foam board and put in the top of all returns and sealed with tape and mastic to help prevent the possibility of any contaminated air from pulling through the returns.

      • That’s very strange. It’s unlikely to be going up then getting sucked down. The video you sent me is horrifying!
        it really doesn’t make sense that your furnace filter isn’t getting dirty with all that debris floating around unless there’s minimal air flow through the system. Is it possible that the air return for the furnace is sucking in debris that just looks like dryer lint? For example, the fibers from cellulose insulation could look similar.
        I’d like you to see how much air flow you have for your HVAC system on the return side. If you place a piece of newspaper up near the return, it should get sucked onto the return air vent with a good amount of force. This is a crude, but effective, test. Given the symptoms, I’m thinking that you may have a large leak in the return air supply for the system. This would suck in any debris near the leak (or leaks) and distribute it all around the house.
        The last thing you noted in your recent comment about sealing up the “returns” – are you talking about the air intake vents in the soffits of the house that you sent a photo of right above your porch light? If so, there should be minimal chance of that being the source of the problem.
        A final comment – from what I’ve read, the Aeroseal system seems very good. BUT – be very, very careful. I had one client who had this done and the company forgot to seal all the air vents in their basement! This lead to sticky glue (the sealant) spraying into their home which covered everything in their basement causing a horrible mess. If you do have this done, you would be advised to walk the entire house with them before they start the sealing and have them point out each and every vent that they’ve sealed. Make sure that they haven’t missed anything.

      • Well we are still trying to figure this dust issue out. Tonight we took flashlights and turned off all the lights in the laundry area and turned the dryer on with towels in it and we didn’t see any change in the particles that are already throughout the house. Then we went outside in the dark and shined our light on the dryer vent, we could see some lint coming from the vent. But what shocked us was all over and around our yard you could see massive amounts of particles swirling in the air, kinda of like what we saw earlier in the day in our bedroom. We live out in a rural area where the homes have 4 to 10 acres. We live on pavement no gravel roads for a couple miles. We drove around our neighborhood and saw this stuff wherever we shined our flashlight. We even went seven miles into town into a neighborhood development and we still saw the stuff. So now we are perplexed. Is our house so leaky we are just basically living in outdoor air? Is it normal to see so much debris in outdoor air?

      • Good detective work.
        At this point, I think the lint diagnosis is a “red herring” and the dust around your house is something else.
        Outside, it’s possible that you’re seeing regular dust, but this time of year, it might also be pollen that you’re seeing outside. I don’t know about there, but around here (eastern PA) everything turns yellow with pollen. So it’s probably different unless there’s something industrial in the area producing huge amounts of lint-like emissions. But that’s a stretch.
        It may also be worthwhile asking your neighbors if they’re experiencing anything like you are.
        Another thing you could do is see how much dust is accumulating on outdoor surfaces. A simple finger swipe across a flat surface every morning would tell you how much accumulation you’re getting and whether that dust is the same color and “feel” as what you’ve got inside the house.

  12. We live in a house built in 2000. The heat/air unit is inside the garage and has electronic filters and there are no filters in the vents inside the house. For the first ten years we had no dust problems. Now there is a fine gray dust everywhere and after dusting it is only a matter of hours before surfaces are dusty again. You can see a build up of the dust in the carpet along the base boards and those areas do get vacuumed. We had an HVAC company come out and they had a machine that they directed towards the windows and vents inside the house and they said we had no leaking issues. Another company told me it was dirt coming in from the windows. No one has looked at the duct work in the attic and unless there is a duct that is fully disengaged I wouldn’t feel competent in looking at the ducts ourselves. Can you recommend the correct type of company we should contact in the Oklahoma City, OK area?

    • The first thing I would check, and it sounds like you did, but just to be sure – are you sure your electronic filter is still functioning correctly? How often do you clean the unit? Have you noticed any change in the dirt that the filter is picking up?

      What type of machine did the HVAC company use to detect the leaks? The best way to check a duct system is to use a device called a “duct blaster” which is a calibrated fan that is used to pressurize the ducts. They seal up all the vents and blow air into the system. By measuring the pressure, they can tell how much leakage your ducts have. If they didn’t do that, then they really can’t tell much about the system.

      I searched on companies that appear to have the proper equipment and training and these came up

      Unfortunately, there are few companies who put the time and money into training and equipment, but these two look good.

      Note: please avoid “duct cleaning” services. These companies can do more damage than good. I’m not saying all are bad, but there are enough out there doing damage, that it’s best to avoid them because you really can’t tell until the damage is done. Plus, many in my field consider it a waste – if your filter is doing its job, then the insides of your ducts shouldn’t be dirty. And, if the dirt is adhered to the ducts so firmly that it doesn’t come out when the fan blows, why would you want to dislodge it?

      • We probably only clean the filters once every three months. I don’t see any difference in the dirt that is on the filters. There are two filter units & two metal screens. We clean them by rinsing them with the hose then let them dry before putting back in. The metal screens are falling apart, but are still in their frames. I have been told no one makes them anymore. I don’t hear as many zapping noises as I used to when replacing the filters anymore.

        I don’t know the name of the machine, but it wasn’t a duct blaster. The person just walked around inside the house and pointed it at the windows and where the walls meet the ceiling.

        Thank you so much for doing the research and finding the two local companies.

      • Ok, so they must have used a thermal camera? Did it have a color screen showing heat? Anyway, it’s not really important. Those are valuable diagnostics, but nothing tells you what’s happening with the ducts like a duct blaster.

        My initial guess is that your electrostatic filter may be failing and letting more dust through the system. It might be worth seeing about having it replaced by a standard pleated filter. Good quality high MERV filters are extremely good at filtering the air. The electrostatic filters have fallen out of favor.
        Another reader just posted some followup to their dusty house problem. They noted that the dust was tested and determined to be dryer lint. Is it possible that this is your problem also? That could be caused by a leak in the dryer vent or connections. It’s definitely worth pulling the dryer and checking this out.
        Good luck! Please let me know what you discover 🙂

  13. How can I find a professional who can help me locate the source of the small white particles that seem to be coming from a ceiling vent in the bedroom? I did not even notice it until a few months ago when I put a quilt with a black background on the bed. Despite daily removal of the particles with a lint remover, they come back the next day. I had a hunch they were coming from the duct above the bed, and your column confirms my suspicions. I’m afraid if I call an HVAC professional, they will try to talk me into getting my ducts cleaned, which if I understand you correctly, will not address the source. The house was built in 2000 and has two attics — one over the garage and the other over the bedroom. Thanks for your help.

    • Hi Lisa, if you post your city/state or metro region, I can do a search in your area for companies that look appropriate.
      What I would do is search on something like: duct pressure testing. That will come up with a variety of results, many of them HVAC companies. As you noted, they wouldn’t be my first choice. Instead, I’d look for something like this company (which was one of the top google hits in my region:
      Look for a specialist in duct testing that is independent. I prefer consulting companies over those that are trying to sell a product.

      Hope that helps!

  14. Great article. I would appreciate your feedback, My house of 18 years has a hall intake where filter would normally go. I had a merv11 air cleaner and filter installed for my furnace in the attic. So now my hall intake goes without a filter(told I can’t use a filter in hall as well as the attic). The hall grill that would normally cover a filter is always dirty. I do believe the house is cleaner and vents look pretty good and I can see that the merv11 air cleaner in the attic does collect a lot of dust. Is this conversion from hall filter to attic as good as I was led to believe?

  15. We have all electric heat even when all ground is covered with snow in our area we still get a smoke like film on windows and furniture. No one ever smokes in the house we have three electric heaters with fans in living room and entryway and the balance of the house is baseboard electric do you have any ideas where it’s coming from ?

    • Cooking? I had that issue in my garage where I’d used my fryer. took me a while to figure that out.
      Not sure what your reference to snow outside is. I must be missing something. What are you thinking about there?

  16. I live in my childhood house, almost 100 years old..It is so very dusty, I started with getting the ducts cleaned, I would actually have to dust every day, allergies, eyes burning..Now after they have been cleaned I only have to dust every 2 or 3 days. I am permanently on allergy pills. Who and where do I start looking for someone who can check for leaks?

    • many areas now require duct pressure testing for new homes or major renovations. I would first call your local Building Department and ask if they can recommend anybody who does duct testing. that would be the place to start.
      however one thing you can do yourself is to look at your furnace especially where the filter is installed if it is located on the furnace. often dust is sucked in and spread around the house by the furnace itself. if the unit does not look airtight, that is you can see cracks in the joints where air would easily be sucked in, those can be sealed and can make a considerable difference.
      the difficulty with old homes is that often compromises are made when installing the ducts. sometimes they run air through the walls without even using any ductwork. that can lead to horrible dust problems.

  17. We have had a new AC unit put in, all new duct work, i have hardwood flooring throughout, and crawlspace. The crawlspace does not have plastic on top of the dirt. Could this be causing dust issues in my house? I dust and the next day I have dust again I can’t keep up with it. My son is suffering with awful allergies and asthma just trying to do all I can to help him.

    • Someone might be able to tell you what type of dust it is which could give you a hint as to where it’s coming from. Normally, unless there’s something disturbing the dirt in the crawlspace, I wouldn’t think that it would cause that type of problem.
      If the dust is like fine lint – white dust, it could be coming from insulation getting into the system somehow. Is any part of the system in the attic? If so, what is the insulation like in there? Blown in insulation can be very dusty and if the air system has any leaks, the dust can get sucked in and blown around the house.
      Look at the air vents where the air comes out. If they look dusty/dirty, then you’ve got a problem with the system because those vents should only be passing filtered air. Then look at the air intake vent for the system. If that duct is really dusty, then you’re probably sucking in dust from somewhere else.
      You should also check the main air filter. Does it get dirty fast? Are you using a good quality pleated air filter or one of those horrible fiberglass ones? A pleated filter with a MERV of 8, 10 or higher is recommended as they do vastly better at filtering the fine dust. Those other ones are virtually useless for filtering anything smaller than dog hair.

  18. Wow, this is a huge problem for us. We constantly have dust, with the downstairs registers always coated (no matter how often i clean them). The problem is that we have NO real ductwork – the wall cavities are used as ducts like you describe. AND our attic is full of blown in loose fill insulation (the fluffy white stuff)! My son has asthma – it’s horrible! i am constantly dealing with dust! My question is – are we doomed bc we do not have duct work??

    • Oh, that’s a sad situation.
      It really depends on your budget. The health of your family is of top importance, but I realize that most people don’t have it in their budgets to redo their air distribution system.
      You might be able to focus your efforts if someone in the family is handy.
      Where is the air handler for your system? Is there any part of the system that is in the attic with all the insulation?
      How does the air filter look? It should catch and filter much of the dust if it’s a good filter. If you’re using one of those cut-to-size filters, they’re really no good. You want a pleated, high MERV filter. Look for a rating of at least 8. Preferably a MERV 11 filter. Try this first and see if that improves the situation. If not, I can give you more tips.
      Check out info about air filters at this link:

  19. The home we moved into so dusty. I can dust one day and the next day you can start seeing dust. We have the good HEPA filters in. At least I thought they were good . Please help! Thanks

  20. I am getting what appears to be white type lint that gets in my eyes and face and is giving me headaches.I had a new furnace put in 10 years ago through a government assistant program that did a shoddy job. I am worried. Can I get cancer from this? They would not address this at the time and I had to pay over three hundred dollars to redo all the ductwork,as it all fell apart.I wonder if I am breathing in insulation?

    • I certainly can’t comment on your specific cancer risk. If it’s that bad, you need to have the material tested. In general however, no modern insulation materials have been shown to have serious health consequences. Yes, some are irritants – for example, handling fiberglass leads to extremely itchy skin. Loose fill insulation, the type that’s blown into attics such as fiberglass and cellulose (shredded newspaper) often are very dusty and if the ductwork isn’t well sealed, can be sucked into the ducts and blown around the house which will lead to a dusty house.
      If you have ductwork in the attic or the main system is in the attic, this would have to be carefully examined for leaks and sealed up. This requires someone with a real eye for detail, but anybody can examine it if they can safely navigate the attic. Look for openings around the blower – seams that aren’t sealed air-tight. Then examine how the ducts are attached and run to the vents. Seams should be sealed and/or taped with special materials. Any gaps will be prone to sucking in dust. It’s unpleasant and time consuming work, but your health comes first.

    • I just had the same done in 2016. My entire home is infected. We had to close off the air condition system due to the debris falling from the vents. It’s a total mess. You might want to check your health. We are having a lot of health issues. We have had many Infections in just over a year. The entire home has been infected. I can’t clean any more I get so sick when I try to clean. I can’t get any help from any agencies. I’ve been looking into it for over a year now. There are regulations listed but no one to report them too. The energy program is running all on there own. All of these programs run on goverment money. There is no goverment agencies to report problems too. I wish I knew this before I had them come into my home. I have photos videos of all the damage. They were suppose to prep the attic before installing the insulation, They did not do it they blew the fiberglass insulation into the attic. It was falling all over the house including us and the animals. The fiberglass would cut into my skin then the bacteria would enter into my body . I am covered with sores. Every nook and cranny in my house had debris falling out of it. My walls now have mold growing on them. I have a brand new fridge that has begun to decay on the side where the fibers fell onto it. I have been living in hell. I can’t find a law firm willing to take it unless I pay them a lot of money.

  21. Our furniture is dusty within 2 to 3 days. We had a mold miser put on our unit we have a new heat pump and also had the electric static filter system put on. We do not have any duct work in our attic. What type of company would we hire to look at our duct work?

    • You can start by asking the company that installed your heat pump for a reference to a contractor that does duct testing and troubleshooting. Often this will be an energy auditor. Depending upon where you live, there may be several qualified contractors or none. But that’s a start.

  22. I have many of the problems described in this well-written piece…I just don’t know what my next steps should be. I change my filters once a month. There is visible dust in the air in the morning light in the living room. I have dust on the clothes and jewelry inside of my dresser drawers in my bedroom. After 4 days, I can easily write my name in the dust in both the living room and the bedroom. I can write my name in the other rooms’ dust after 8 days EXCEPT for the “guest house”, which shares a wall with the main house but has its own HVAC system. It does not get dusty for weeks and weeks even though I open and close the door on a regular basis. I had an Energy Audit by a company that does not sell or install HVAC equipment. They did not have solutions, although I was not convinced of their educational background. (I am a Mechanical Engineer…but have not practiced for a while). One last thing. In the summer, there is a cool space in the living room that I cannot pinpoint. Same in winter…a warm space. So…I’m pretty sure that faulty ductwork is the issue. Where do I go for help since my first Contractor was unable to find a solution? I live in the metro Phoenix, AZ area.

    • I’m pretty sure you nailed it. Since the area on a different HVAC system isn’t dusty, there’s a really good chance that you’ve got duct leakage that’s sucking in and blowing dirt all over your home. It’s shame the energy auditor you had in couldn’t determine the source/location of the leak.
      You’ve also noted the room that gets hot/cold. With a thermal camera, it would be really easy to see the source of that issue. It might be related to the dust problem or it could be just another section of duct that’s not sealed well.
      Are your ducts accessible? Do any run under the house or through other areas which could be dirty/dusty?
      When you change your filter every month, is it really dirty? Are you using higher MERV pleated air filters? I like using those with a MERV from 9-12. I get mine from Nordicpure – good quality at a much lower price than the big-box stores.

      Many home testing companies have a device called a “duct blaster” which is used to test for air leaks. I used to do diagnose this type of problem using a duct blaster and a theatrical smoke machine. You blow the smoke into the fan that supplies air to the duct blaster. Then, wherever there are duct leaks, you can see the smoke come out. This is great for ducts that you can see, like in basements and attics. But if the problems are hidden somewhere inside the house, it probably won’t help.
      Hope this helps you track down the problem. These can be really frustrating!

  23. I live in a double wide home I have dogs that are regularly bathed I have DIRT in my home. I have it on my dishes in cabinets its everywhere I can not keep it cleaned HELP

    • Sounds bad! Have someone check your ducts. They’re probably sucking in lots of dust and dirt from under the house.
      Temporarily, you can put filters over the vents where the air comes out for the AC / heater. You don’t want dense filters as that will impede airflow too much, but you can use the mesh filter that can be cut to size. This will also confirm that the dirt is coming from the vents because the filters will get dirty.

  24. I live in a house built in the mid 60’s in Georgia. My heat sources are two 33 BTU Propane, vent free fireplaces, one upstairs, one downstairs. My A/C’s are window units, one 11,000 BTU for the Master Bedroom and Bathroom and two 6000 BTU units in 2 Bedrooms. I don’t have window screens in place so my windows are never open. Despite all of these things, this is the dustiest house that we have ever lived in. We have hardwood floors throughout the upstairs and I cannot keep them clean and dust free. The downstairs is fully tiled but we have a terrible problem with spider and dust-webs. I can sweep and mop and one week later, the dust and webs are back. I have 4 small dogs, all who are non shedding and hypoallergenic, so I am at a loss for what makes my floors, walls and ceilings so dusty all of the time.

    • Often dustiness can be caused by a “leaky” house. Do you feel drafts?
      The spider webs are a sure sign of drafts. Spiders like to build their nests where there is air flowing past because that’s where insects come from. So I would star looking at the windows and doors near where the webs are and work on sealing them up.

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