How to Clean Drywall Dust Out of Air Vents and Returns

That Cleaning Girl · Post-Construction Cleaning

You cleaned every surface, the house looks great, and two days later there is a fine gray film on the counters again. Nine times out of ten, the culprit is the vents. If you have not read it yet, How to Get Rid of Drywall Dust After a Remodel covers the dust on walls, ledges and floors. This one goes after the dust hiding in your air system.

Why vents fill up during construction

Your HVAC system works by pulling air through return vents, running it through a filter and pushing it back out through supply vents. During a remodel or a new build, that air is full of drywall dust, sawdust and fine debris. Some of it gets caught in the filter. A lot of it settles on vent covers, inside the first stretch of ductwork and around the return grille.

On new builds, vents are sometimes left open while drywall is sanded, so dust can get deeper into the system. Once the house is cleaned and the system starts running normally, that dust gets pushed back out into the rooms.

What you can clean yourself

There is a lot a homeowner can do safely without opening up the ductwork:

• Vent covers and grilles, front and back
• The first few inches inside each supply opening
• Return vent grilles and the area right around them
• The air filter itself
• The floor and wall right around each vent

Deeper duct cleaning is a separate job for an HVAC company. It is not something a house cleaner does, and it should not be tried with a household vacuum and a broom handle.

How to clean supply vent covers

Most supply vents in ceilings, walls or floors are held on with a couple of screws or simply sit in place.

1. Turn the system off so you are not blowing dust around while you work.
2. Vacuum the face of the vent with a brush attachment.
3. Remove the cover if it comes off easily and wash it in warm, soapy water.
4. Vacuum the first few inches inside the opening while the cover is off.
5. Dry the cover completely and put it back.

If the covers do not come off easily, a vacuum plus a damp microfiber cloth wrapped around a butter knife works well for wiping between the slats.

How to clean return vents

Return vents are usually larger grilles, often in a hallway or ceiling, and they tend to collect the most dust because they pull air in. Vacuum the face of the grille thoroughly first. If the filter sits behind the grille, open it, remove the filter and vacuum around the frame where dust builds up. Wipe the grille slats with a barely damp cloth, let them dry and close it back up with a fresh filter.

The filter is the most important part

If you only do one thing after a remodel, change the filter. A filter that has been running through construction is often clogged with fine dust, which makes the system work harder and lets more dust slip through.

A good rule of thumb is to replace it right after the dusty work is done, again after the final clean, and once more a few weeks later. Use a filter rated for your system. If someone in the house has allergies, ask your HVAC company whether a finer filter is right for your unit.

Run the fan, then clean again

Here is a trick we use after big jobs. Once the vents are cleaned and the new filter is in, run the HVAC fan for a while to pull loose dust out of the air and into the filter. Then do a light touch-up dusting of the rooms. It sounds backward, but it catches the dust that was going to settle anyway, so your clean holds up longer.

In our hot summers, the AC runs nearly nonstop, so vents that were not cleaned will spread dust quickly. The same goes for those chilly mornings in winter when the heat kicks on for the first time since construction finished.

Signs your vents still need attention

• A gray film returns to surfaces within a day or two
• You see visible dust puffs when the system turns on
• There is a dark ring of dust on the ceiling around a vent
• The air smells dusty or chalky
• The new filter looks gray after only a short time

If these keep happening after vents and filters are clean, it may be time to call an HVAC company about the ducts themselves.

Clean vents, cleaner house

Vent covers, returns and filters are small, but they decide whether your clean lasts a week or a month. Get them done along with everything else, and the dust stops coming back. For a full top-to-bottom job in Red Oak, Waxahachie and the surrounding area, see our post-construction cleaning service.