What Causes Fine White Dust in a House?

Do you find yourself constantly cleaning the house from fine white dust? Once you eliminate the root cause of the problem, you’ll finally be able to spend your precious time on something more exciting.

The most common source of white dust is ultrasonic humidifiers filled with tap water that has high mineral content. However, such things as cheap HVAC filters, dust mites, leaky ducts, and drywall dust can also contribute to the accumulation of white powder in your house.

Why Is My House So Dusty All of a Sudden?

The layer of dust that settles around the surfaces of your house can be a combination of many little things:

  • Cheap and dirty HVAC filters
  • Dust mites hiding in the carpet
  • Open doors and windows
  • Excess dust build-up on furniture and curtains
  • Leaky ducts
  • A poor dusting technique
  • Pets

Read: Why Does Air Purifier Have White Dust?

Why Is My New Build House So Dusty?

The chances are high that the dust that you’re dealing with in a new house is the construction dust and fine sanding particles

To get rid of it, you would have to wipe down every surface in the house. Use a damp microfiber cloth to clean even the inside of the cabinets and the rooms that were closed.

What Causes Fine White Dust in a House?

White dust is usually caused by minerals present in water that you use to fill the tank in your humidifier.

Dust from the carpet and the dust coming in through open doors and windows can sometimes appear white. Paper products and your heating and cooling system can also be a source of white powder. 

Read: Why Is My Humidifier Leaving White Dust?

Do Humidifiers Create White Dust?

Ultrasonic humidifiers are devices that can start to produce white dust if you fill them up with hard water.

Other types of humidifiers, like steam vaporizers and evaporative cool moisture humidifiers, are not capable of creating white dust as all the impurities that the water might contain get ‘trapped’ in the device.

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White Dust Falling from Ceiling

This dust falling from your ceiling might be drywall dust or small particles of paint coming off.

Try wiping the ceiling with a clean cloth and warm water, if the cloth becomes white, then it looks like the paint is to blame.

Thoroughly cleaning the ceiling, priming it, and then applying a fresh layer of paint should fix the issue (you’ll either get rid of the source of the problem, or you’ll ‘lock’ all the dust in).

White Dust from Heating System

Your HVAC system can certainly be the source of white dust and there are quite a few things that can cause it:

  • The dust is the remnants of film or oil in your new HVAC system
  • The high salt content in the air might be to blame if you live close to the coast
  • If you have a humidifier installed in the system and you live in an area with hard water, then it’s because of the minerals in the water
  • A fine chalky powder can also be a result of a carbon monoxide leak

Read: Can You Use Tap Water In The Humidifier?

What Is the White Powder Coming from My Furnace?

If the amount of white powder coming from your new heating system started to decrease over time, then lubricants used during the manufacturing process were the source of the dust. The lubricant film can create white flakes that, later on, will find their way into your house, but don’t worry – the powder is non-toxic.

Soot accumulations on the furnace or a white chalky powder can be indicators of a carbon monoxide leak. This might happen if you have a faulty burner or the heat exchanger had cracked.

This is an extremely dangerous situation. If you have noticed white flakes coming from the furnace and the unit is not operating properly, then turn the system off and call a professional. 

What Is the White Residue in a Gas Furnace?

If your combustion exhaust venting is not adequate, then the gases will have a chance to cool down before they reach the outdoors. The combustion gases can end up reacting with the galvanized steel on the inside of the vent.

As a result, zinc hydroxide is created. This substance then ‘slides’ down onto the furnace where the rest of the remaining moisture evaporates, and the product turns into zinc oxide (a white, powdery residue).

In older gas furnaces that have vents made out of ungalvanized steel, the residue will be not white, but brown (as the end product is iron oxide).

Read: How To Prevent Mold In A Humidifier?

What Is White Dust?

When referring to ‘white dust’ people usually mean the powder that comes out of a humidifier. In such a case, this white dust is the byproduct of the minerals that are present in water.

You will most likely experience such a problem, if you have an ultrasonic humidifier and if you tend to use tap water to refill the device. In plenty of areas, tap water can be hard which means that it has high mineral content.

During the humidification process, not only the actual water but also these minerals get released into the air. The latter end up setting on your furniture and other surfaces.

What Does White Dust Look Like?

If you have an issue with white dust, then you are going to notice white specs on the furniture and other objects around the humidifier.

What Is the White Powder Coming Out of Vents?

The white dust coming out of your vents can be a result of the corrosion of galvanized steel

If there is something wrong with the combustion exhaust venting, then the gases might react with the galvanized steel – the white dust is the byproduct of this interaction.

What Is the White Dust in My Bathroom?

  • Your towel will shed lint every time you use it
  • The extractor fan might be drawing in plenty of dust from the surrounding rooms
  • Make sure that it’s not mold powder as sometimes it can be white
  • Even the little fibers from the toilet paper can contribute to the amount of white dust in the bedroom
  • It might also be sheetrock deteriorating

Read: Why Is House Thermostat Reading The Wrong Temperature?

Is White Dust Harmful?

There are no studies that have proven that white dust from humidifiers is harmful. But you might want to switch to distilled water or a steam vaporizer, just in case.

Inhaling mineral dust doesn’t sound like a healthy thing to do. Moreover, there have been cases, when children developed chronic lung disease because of this white powder.

How Do You Get Rid of White Dust?

To get rid of white dust for good, you would have to tackle its source:

  • Use only distilled water to fill the humidifier’s tank
  • Get a demineralization cartridge
  • Or purchase a humidifier that can’t produce white dust

To clean the white dust stains from the actual humidifier, you would have to soak the parts of the device in a decalcifier, white vinegar, or bleach.

How Do You Get White Powder Out of Carpet?

You might notice white powder on your carpet, if you have been using a certain carpet cleaner or carpet glue or if you like to clean the rug with baking soda. By the way, old carpets can start to deteriorate, at one point, and the process might result in white dust.

In a lot of cases, the only thing that you can do is thoroughly vacuum the carpet a few times.

Can Air Humidifier Reduce Dust?

Air humidifiers are not the kind of devices that can help with dust. They simply add moisture to the air.

Bear in mind that high humidity can actually create the perfect environment for dust mites.

Does Opening Windows Reduce Dust?

Opening the windows and doors can actually increase the amount of dust in your house. By doing that, you are letting pollen, dirt, sand, spores, and even tiny parts of insects in.

Is It Normal to See Dust Particles in the Air?

If you notice a few dust particles floating in the air on a sunny day, there is nothing to worry about. But if there is a lot of dust, then the air circulation in your house is not effective and the indoor air quality might not be great.