How To Clean Drywall After Sanding

The drywall is installed, seams taped and joint compound applied, everything feathered and sanded smooth, but before you get to painting, how do you best clean your drywall after sanding?

The key to a flawless paint job is good preparation. Installing drywall is already a grueling task, so it’s important all that hard work not go to waste with a hasty cleanup and botched coat of paint.

Here are the steps you need to take to make clean up as easy as possible and ensure your walls are picture-perfect after sanding your drywall. 

how to clean drywall after sanding

Cleaning Drywall After Sanding

Sanding and scraping drywall leaves a lot of dust that will botch your paint job if it’s not properly cleaned. You will need to wipe down your walls with a microfiber cloth or sponge. Leftover dust forms a thin film that can cause the paint to flake off the walls.

Depending on how much dust is lingering in the air, you might have to go over your walls several times.

Cloths and sponges should never be wet – lightly damp is fine, but the joint compound is very lightweight, and if you’ve taken the time to feather and smooth it to perfection, adding water could completely undo all the hard work.

Overly-wetting drywall is also a no-no, drywall will absorb a lot of water which can lead to splitting and cracking.

However, there are some tips and tricks that will make the time-consuming job of cleaning and prepping your walls a little easier.

The best way to make cleaning your drywall easy is to prepare ahead of hanging and sanding. There’s nothing more frustrating than wiping and mopping up drywall dust for hours, only to have all the airborne dust settle back onto your clean walls.

Before you even begin the installation, cover the floors and any furniture still in the room, taping down the edges. When you’re done, you can simply roll up the dust and dispose of it. 

Clean as you go. No, it’s not a waste of time to get rid of piles of dust as they collect. The less you have to sweep, the less will get into the air, and the quicker you can get to painting. 

When you’re ready to begin the big clean up before painting, you will need to sweep first. Gently collect the drywall dust into piles in the middle of the room- overly zealous strokes will fling more drywall dust into the air.

Wait an hour or so after your first sweep to let some of the dust settle. You can vacuum up small amounts of dust that have collected in corners with a wet/dry vacuum, but never use a regular vacuum – the fine dust will likely overload your vacuum motor.

Use a wet/dry vac aka ShopVac, preferably with a heavy-duty HEPA filter to keep particles from flying out of the exhaust.

Related: Best shop vacs for drywall dust.

Drywall dust isn’t toxic but sanded joint compound may contain silica, a much more harmful substance. 

Wipe down your walls and ceiling.

Starting from the top, take a microfiber cloth or lightly damp cloth, or a nearly dry sponge and sweep towards the bottom. Dust will pile up – simply use your ShopVac or collect it with a rag and dispose of it in the trash. You may have to go over your walls and ceilings a few times.

To check the cleanliness of your walls, take a very dark or solid black colored t-shirt or cloth and blot it against the walls. You should be able to see how much dust is still clinging to the drywall.


Use a Sanding Attachment 

drywall sanding attachment simply attaches to a standard shop vacuum and cuts down on dust while you work.

Attachments start around 20 bucks but professional-grade sanding poles with vacuum attachments get well over $100. If you’re doing just one room, it’s probably not worth the investment, but if you have a large area to sand, you can always rent.

You will still have to clean up drywall dust that escapes the vacuum attachment. 

Use a Swiffer

This is a relatively cheap investment that will really pay off, and if you’ve already got one, you should use it.

Swiffers are a super-easy way to hit your ceiling and clean high up on walls.

You can buy the swifter cloths, or just use your own lightly damp cloths to save a few bucks.

Just stroke downwards with your swifter, and change the dirty cloth/Swiffer pads as needed. 

Use a Mop

A sponge mop (not a string mop- these are too wet) will also work for cleaning ceilings and high wall spaces but is more time consuming than the Swiffer.

You have to ring out your mop really well so it doesn’t wet down the drywall or joint compound, and continuously clean the mop head as it collects dust.

It’s still a good way to get hard-to-reach places without resorting to climbing up and moving a ladder constantly.  

Use a Sweeping Compound

Sweeping compounds are an oil-based or water-soluble tacky powder that you shake over floors to help weigh down fine dust particles. Bags of sweeping compound start at about twenty dollars a bag.

Some joint compounds contain silica, which is a dangerous particle to inhale, so if you’re particularly worried about sweeping particles into the air, a sweeping compound might be for you.

Be aware, some require you to leave it for 24 hours before sweeping up. 

Congratulations on all your hard work. If you’ve done a great job installing, or you’re just cleaning up after a remodel, the hard part is over.

With some good planning and a little elbow grease, you’ll be ready for painting in no time. Take your time to make sure your drywall is good and clean before you start painting.

Remember, you may have to repeat some of these steps more than once, but just be patient. When your black cloth or t-shirt comes away clean, you’re ready to go.

Don’t forget to mask up, and happy painting.