Wet Sanding Drywall: Pros and Cons Explained

Wet Sanding Drywall: Pros and Cons Explained

Adding a bedroom, creating a beautiful gallery of your art collection, hanging that huge TV — all these things are difficult if not impossible without walls, and in most cases, that means drywall. While this material is inexpensive and ubiquitous, it’s not without its drawbacks. Among the biggest is that finishing drywall involves sanding joint compound, or drywall mud, which is a decidedly messy endeavor.

If only there were an alternative to the dust-creating process of sanding drywall. Enter wet sanding drywall. With this technique, it’s possible to complete small or medium drywall projects with as little dust as possible. Learn more about wet sanding drywall and when to turn to this mess-free option.

Wet Sanding Drywall: It’s Not an Oxymoron

Drywall has long been the standard method of creating interior walls and ceilings in North America. That’s because the rigid sheets of drywall, when properly installed and sealed, create a strong, smooth wall surface that’s ready for paint — or whatever else you have in mind.

While the material itself is easy to work with, getting to a finished product is time-consuming and messy, as creating a finished wall requires affixing drywall sheets to wall studs, and then applying special tape and adhesive to create a continuous surface.

A crucial step in taping and mudding drywall is the sanding process, which must be done in at least three sessions to ensure the wall (or ceiling) is finished. This involves sanding down excess areas of drywall mud or joint compound, then applying a new layer, and then sanding again, and so on.

The key to a seamless drywall finish is in the details, especially the sanding process, which is so messy that professional drywall sanders have a special page on the CDC’s website detailing the hazards they experience. While there are options for dry sanding that can reduce exposure to dust, for many people interest in creating a low-dust experience when sanding drywall, wet sanding is the best option.

Wet sanding has applications far beyond drywall, and one of the most popular uses for wet sanding is in automotive repair. Many of those who work in repairing and restoring paint on vehicles routinely use wet sanding to remove tiny particles on the surface of a vehicle to prepare it for a new paint job. The final product is, ideally, a smooth, shiny surface that looks like it just rolled off the factory floor.

Wet sanding drywall is done in a similar method to traditional dry sanding, though it will take longer, which is one of the disadvantages we’ll talk about later. Here’s a quick tutorial of the steps involved in wet sanding drywall, and you can learn more in this video.

  1. Make sure you have a good drywall sponge. The goal is not to aggressively obliterate the high spots of the drywall mud but rather to gently smooth them out, so wet sanding needs to be done with a sponge rather than a sanding block. Depending on your preferences, you may prefer a softer sponge like this one, or one that has a more abrasive side, like this one.
  2. Prepare a bucket of warm water. Submerge your sponge and then ring it out to remove excess moisture. The goal is a damp but not dripping sponge, wet enough that it can loosen the now-hardened joint compound that’s been applied to the drywall.
  3. If your sponge has an abrasive side, first use that side to shrink and smooth out obvious areas where joint compound is elevated off the surface of the wall. These should be clear immediately, but you can rub your hand along the wall if needed to identify them.
  4. Using a wide, circular motion, pass the sponge along any obvious high areas of joint compound, pressing just hard enough to slightly smooth the surface. If you press too hard, you could dislodge the joint compound, which would then have to be redone.
  5. The sponge will begin to become caked with drywall mud and you’ll notice you get less resistance, which lessens the effectiveness of your sanding. As this happens, rinse and wring the sponge using the bucket.
  6. Once you feel satisfied that large areas of high spots in the mud have been knocked down, with the smoother side of your sponge, repeat the process of smoothing out the mud along the edges of where it’s been applied.
  7. After your second pass, if imperfections still exist along the joints, you’ll need to turn to dry sanding as too much water will damage the drywall itself.

Pros of Wet Sanding Drywall

What are the biggest benefits of wet sanding drywall vs. traditional dry-sanding methods?

  • It’s a cleaner method, as it essentially eliminates the dust that’s common with drywall sanding. With dry sanding, it’s usually necessary to tape off the room that’s being sanded because drywall dust can travel to other spaces if it’s not contained. (Power drywall sanders with extraction tools can help with this, but they can be pricey.)
  • Wet sanding requires fewer tools — just a bucket, sponge, and some water. While dry-sanding tools (at least the non-powered varieties) aren’t necessarily pricey, it’s hard to beat using materials you may already have on-hand.
  • Because it’s done up close, it may be easier to create a specific finish in the drywall, as you have more tactile control over the fine details. This will depend quite a bit on the state of the drywall mud and how much sanding you need to do.

Cons of Wet Sanding Drywall

If wet sanding drywall were a perfect option, nobody would ever use alternatives. But there are some major drawbacks. Here’s a look at the biggest:

  • It’s time-consuming. Particularly if it’s being used for a large area, the process is long and labor-intensive, much more than dry sanding. While the steps are simple, the process must be repeated again and again for each new section of joints or mudded areas, and the sponge must be wrung out regularly to ensure effectiveness. While dry sanding also must be done multiple times, the process is quicker, and tools like pole sanders make it easy to sand large areas quickly. For this reason, it’s not ideal for entire rooms or other large areas.
  • The process is also much more physical than dry sanding. This is because you’re using your arms to make the big, sweeping motions, and there aren’t really any good ways to shortcut this process. Wet sanding will tax your muscles far more than dry sanding.
  • Wet sanding may delay your timetable. If you’re eager to begin priming and painting your newly drywalled surface, wet sanding is perhaps not the right solution. While you’re not meant to use a great amount of water in this process, the drywall mud does still grow damp, and you must wait for it to dry completely before you begin painting.
  • Because you’re using a bit of water and a sponge, the finish will probably not be perfectly smooth, and you’re likely to see small waves in the surface once you’re done — if you look very closely. For walls that need an extra-smooth finish, wet sanding isn’t a great option.

Tips for the Best Finish

For those interested in tackling wet sanding in their next drywall project, here are a few tips and tricks to get the most out of this method:

  • Move slowly. It’s tempting once you get the hang of the process to wipe the mud rapidly (after all, we just warned you that this is a time-consuming process). But one of the big benefits of wet sanding is that by using a small amount of moisture and gentle friction, you’ll soften the edges of the mud and smooth it out. Going quickly creates more friction than you want.
  • The purpose of using a sponge for wet sanding drywall is that the light friction will gently knock down and smooth out the surface, so in addition to working slowly, remember not to apply pressure. Let the sponge and water do the work, not your arm.
  • Consider using wet sanding after you’ve done one or two passes with dry sanding. That way, you get the best of both worlds and allow the wet sponge to feather out the edges of the mud.
  • As mentioned, it’s likely the finish won’t be perfectly smooth, but that makes wet sanding ideal for walls that have a little bit of variation already, such as a textured wall that’s being patched.
  • Change your water as needed. If the water you’re using starts to look milky or is impossible to see through, dump it out and refill the bucket.

The Bottom Line

Even in an open-concept world, we still need walls, and creating a solid finished wall takes time and energy. But using techniques like wet sanding for your drywall projects can be the key to a beautiful result and an easier cleanup.