Not every drywall repair requires new sheetrock installation. In a lot of cases, a simple coat of drywall mud can hide gouges and unfinished areas. This article shows you how to make simple mud patch repairs to your walls. And carry out the whole process in one hour or less!
A 13″ MUD PAN is perfect for mixing and containing small batches!
Likewise, a 12” TAPING KNIFE gives great, broad smoothing ability.
A HEAT GUN is the secret to FAST mud patches! WAGNER makes a great one:
Step 1: Choose Your Joint Compound
Are you ready to tackle drywall repairs? Many homeowners buy 5 gallon buckets of joint compound. Admittedly, these bucket portions can be helpful for mudding an entire room. However, they are overkill for patching small areas.
Introducing Hot Mud
A far more effective solution is using 20-minute joint compound. This fast-setting powder is perfect for carrying out numerous small projects over time. (It can be found at Lowes or Home Depot.)
Typically, you just need a few cups for a small repair. Then, store the rest of the compound in a heavy garbage bag. Tie off at the top to prevent the powder from taking on moisture.
I realize you may be intimidated by the idea of mixing your own drywall mud. But, once you see how easy it is in the steps ahead, you might change your mind.
Step 2: Prep The Area
To begin your repair, lightly sand the area where you’ll apply your mud patch. (Here, a wall-mount sink was removed..)
When you sand the wall, you provide the area with more “tooth”. In other words, you roughen the existing texture. That makes the new mud grip the surface better.
Use your drywall sander paddle to pass a low-grit mesh pad over the area in sall circular sweeps. Be sure to scour a space several inches larger than the repair site itself. This helps when you “feather” the drywall mud outwards.
Step 3: Mix Your Joint Compound
Pour just a little bit of water into your mud pan. About a ¼” depth is good to start with. Now, use a cup to begin shaking the dry joint compound into the water in the pan.
Cover the water with joint compound (the powder will mostly float on the surface). Then, use your margin trowel to mix the components.
Drag the trowel edgewise through the center of the pan slowly. Sudden motions at this point will just cause a powder explosion! Very carefully swirl the two parts together until the water begins to soak the powder. When this happens, you have a lumpy paste in the pan.
Now, work the trowel through he mix more vigorously. Periodically scrape the walls of the pan. This pulls the paste towards the center, where it can be mixed effectively. It also keeps your pan clean.
What Result Am I Looking For?
Ultimately, the goal is to achieve a consistency similar to peanut butter. The mud should hold the shape of a groove when you drag your finger through it. Very importantly, eliminate any chunks or bubbles in the mixture. That keeps pockets of air or dry powder from showing up on the wall later.
If your mixture seems too soupy, add a little more compound. If it seems too doughy, splash in a little more water. A little experimentation will help you get the right combination.
Here’s a good video for mixing small batches:
Step 4: Let The Fresh Drywall Mud “Set Up”
When your drywall mud is the right consistency, set it aside for a full minute. A chemical reaction is taking place in the pan. The mud is achieving something known as a “false set.”
I have no idea why this occurs, but every good plasterer knows about it. The compound thickens somewhat at this point. But don’t worry. It’s just a natural part of the chemical process.
When a minute is up, mix the mud again. This quickly softens the mud in the pan. Work it right back into a smooth consistency. Now, you’re ready to apply!
Step 5: Trowel The Mud Onto The Wall
We’re not covering tape joints in this project. Therefore, there’s really no point to use anything but a 12” drywall knife. The wider blade will really help “fan out” the material. (If your patch area is really small, use a smaller knife, 4″ or 6″).
Press the blade of the knife into the compound and drag some to the side of the pan. Now, press firmly. Scrape the blade up the wall in a smooth draw. This pulls the mud on the edge of the knife from the mud in the pan. As well as you can, minimize ridges.
Keep It Clean!
If you have some compound on the back of the knife, scrape it off on the top edge of the pan. Also, make sure there aren’t any globs hanging off the sides of the knife. You want a clean “line” of mud sitting on the edge of the blade.
Spread the mud onto your repair area. Leave the thickest amount in the center of the repair area. Work your way outward to the edges.
Don’t worry about ridges in the patch at this point. You just want to get the whole area covered. Make a soft, low mound of mud, thin to non-existent at the edges; deepest in the middle. (By deep, I mean no more than 1/8” or so.)
Keep a bucket half-full of water nearby for cleaning off your tools. Scrape any excess mud into a trash bag, then clean out your mud pan thoroughly in the bucket. Let your pan and drywall knives dry to prevent rusting.
Your first coat is done! You’re ready for the interesting part…
Step 6: “Reactivate” And Scrape The Drywall Compound
I learned this trick from a master plasterer. It’s a bit difficult to get the hang of. But when you do, you speed up any plaster repair ten-fold!
Wait until the drywall mud becomes a bit stiff on the wall. It’s hard to say for sure when this will happen. Factors in your house like air temperature and moisture content cause the mud to dry faster or slower.
For twenty-minute joint compound, though, it’ll generally occur after about 15 minutes. The compound begins to take on a dull, greenish color. The mud no longer moves when poked or scraped.
When this happens, use a spray bottle to squirt a fine mist of clean water onto the mud. Be sure to soak all the mud. (You may want to tape a piece of plastic to the wall below—water dribbling down will get on your base trim otherwise.)
When you wet the mud at this stage, you briefly “reactivate” it. This makes it workable for a few more minutes.
With the area thoroughly wetted, pull your 12” knife over the area. Do this from the outer edges toward the center.
When you do this properly, the mud begins to smooth out. A slurry of mud paste builds up on the edge of your blade. Keep it there! It will fill in divots and pocks as the blade travels over the surface.
Don’t go overboard here. You just want to flatten out the highs and fill in the lows on the wall. It drastically cuts down on the need to sand later. It will also set you up for the next smooth coat!
Step 7: Dry The New Drywall Mud With A Heat Gun
(WARNING: This next step speeds things up tremendously if you want to try it. BUT BE CAREFUL! A heat gun produces an incredible amount of heat. If you misuse it, you can even cause a fire.)
Painters and drywallers speed up the set time of their hot mud by using heat guns. This quickly dries wet paint and mud. I utterly rely on heat guns for small repairs like this.
Plug the gun in, switch it on, and position it a few inches away from your wall patch. Move the gun around in a pattern. Pass it back and forth repeatedly over the entire area.
The heat from the gun causes the patch to “parch,” or go through the drying process very quickly. You’ll see this happen as the compound goes from a smooth, dullish gray to a bone-white color.
Don’t let the gun point at any one area for too long! Move it around until the whole area is relatively dry.
Set the gun aside when the patch is fairly dry. BUT BE EXTREMELY CAREFUL! The nozzle is hot enough to burn anything it touches. Ff possible, hang the gun up by the little hook provided, or set it on a stone or concrete surface.
Step 8: Repeat The Process
At this point, begin the entire process again. Lightly sand the wall patch with a medium-grit mesh, just enough to give it a little more tooth. Then, mix up another batch of joint compound and trowel it over the first patch.
Pull this layer out just a little wider than the first. Remember to pull the mud from the perimeter towards the center. Focus on getting a smooth finish this time around. Work with smaller amounts of mud on your knife.
When the second coat begins to set up, repeat the spraying process. Then trowel mud towards the center of the patch once more, smoothing the mud.
Ideally, all traces of the old damage should be gone now. Your patch surface should look fairly smooth. Dry it with your heat gun. But clean your tools first!
Notice that dark spots emerge through newly dried areas after a few moments. This is moisture escaping from deeper regions of the patch. Pass the heat gun over these areas until no new dark spots emerge.
Step 9: Sand the Drywall Patch
Walk away for a little while at this point, if you want. In a warm, dry house, the 20-minute mud will finish drying pretty quickly.
Check that the whole patch is bone-white and extremely hard. If so, use a fine-grit mesh on your sanding paddle to sand the entire area. Feather the perimeter carefully! Don’t scar the old paint and drywall around your patch by being too aggressive.
If everything goes according to plan, you have a well-blended patch. Finally you’re ready for primer and paint!
Obviously, there are skills that need to be practiced in order to make this process routine. But, drywall mud is really pretty forgiving.
Remember, you can do as many coats as you like. Just use smaller amounts of mud for each subsequent coat. And ALWAYS be careful with the heat gun.
With twenty-minute mud and a few drywall tools, you can to patch superficial drywall damage in record time!
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