Bathtub and shower tile and grout can get notoriously dirty. Dirty isn't even the right word since mere dirt is preferable to the slimy, moldy debris that accumulates on bath tile if it goes too long before being cleaned.
If you have ever power washed your driveway or walkway, you may have looked over at the house and wondered whether you can transfer operations indoors to the bathroom. Is it possible to use the same massive waterpower that you use to blast away moss, dirt, and oil from the driveway on indoor bathroom wall tile?
In a sense, this is possible. You can harness your pressure washer's intense water jet and apply it to indoor tile. It can clean better than steam cleaning. It might inflict less damage on your tile than you expect, perhaps leaving the tile totally unscathed. With this project, this is the gamble you take.
While this method is fairly effective, if you are envisioning a total replacement for traditional hand scrubbing, one that you can do on a weekly basis, your fantasies will fall short of reality. Power washing your indoor wall tile should be an infrequent activity. Depending on the health of your tile grout, the grout may suffer or not. Setting up and taking down cleaning operations can be burdensome.
In the end, you may want to consider experimenting with this relatively simple and low-labor project that takes far less time to clean an entire shower or tub than with manual scrubbing.
How to Use Your Power Washer Indoors to Clean Tile
Power washing your indoor tile is heavy on set-up and tear-down procedures. Overspray is an inevitable byproduct of power washing your tile, but you can take precautions against this. Plastic sheeting on the floor and ceiling can help keep the space more dry, but it will never remain completely dry. In this regard, it helps to have bathroom flooring that holds up well against moisture: ceramic or porcelain tile, natural stone, vinyl plank, or vinyl sheeting.
If you have moisture-intolerant flooring such as engineered wood, solid hardwood, or laminate, you may not want to do this project. This is a project only for indoor wall (vertical) tile, not floor tile. Finally, you will want to be cautious with refinished, or reglazed, tile and tubs, as the finish paint may chip away.
Locate the Pressure Washer Outdoors
Do not run gas-powered washers indoors, ever. Carbon monoxide poisoning will occur whenever you run gas-powered machines in enclosed spaces. Due to water leakage in the connections, you'll even want to keep the electric power washer outdoors.
Open a Window and Run the Hose
Ideally, this is a warm-weather event because you'll want to keep the bathroom window open for a few hours to promote drying-out.
Place the power washer close to the bathroom window. Plug it into the nearest GFCI outlet. Run the hose and sprayer through the bathroom window.
Widen the Spray, Lower the Pressure
The biggest danger of this project is that you may chip away tile grout. Pressure washers are strong enough that this can easily happen. Keep the spray in a medium-wide position. Pinpoint spraying will almost guarantee that you lose grout. Widening the spray reduces pressure, but it also helps to have an inexpensive electric pressure washer that maxes out at around 1,400 psi or a more expensive model with adjustable psi settings.
Guard Against Overspray
You want as much water as possible to drain back into the tub and down the drain. However, it is inevitable that you will have overspray, and some of it will end up on your bathroom floor. Limit overspray by never pointing the gun perpendicular to the tile. Instead, keep it at a 45-degree angle and always point down or sideways. Have plenty of large beach or bath towels nearby to mop up water.
One way to limit overspray is to run a wall of plastic sheeting in front of the tub or shower, holding it to the ceiling with Zipwall poles or taping it to the ceiling. Tuck the bottom of the plastic into the tub, so that water will drain back into the tub.
When you lay plastic sheeting on the floor, extend the sheeting 12 inches up the wall to protect the lower section of the walls and prevent water from spreading under the baseboards.
Be Cautious of Caulking
Next to the grout, caulking is another element that may be stripped away by the power washer. You have a few options with this. If the caulking is bad to begin with, you may choose to spray with abandon, knowing that you are going to re-caulk the tub or shower after you finish the project. Another option is to widen the spray even more when you approach the caulking and run the spray across the caulking. The final option is to keep the spray moderately wide, but entirely steer clear of caulking.
Start at Top, Work Downward
Begin by spraying at the top of the tile, working in horizontal runs. After you finish a complete run, move down about 6 inches and do another run. By starting at top, you ensure that debris keeps moving downward, away from cleaned areas.
Mop Up Residue
Considerable debris and residue will collect on the tub deck, soap dishes, and other horizontal surfaces. Rather than shooting these areas with the power washer in an attempt to remove the residue, use sponges or clean rags to wipe it away. Whatever you do, never leave this residue behind as it will harden again.