How to Mud and Tape
Doing drywall work may seem daunting if you’re just starting out but it is absolutely within the ability of most home DIYers as long as you’re willing to have a little patience. While that’s true in general, nowhere is it more true than in the mudding and taping (or “finishing”) stages. Hanging rock requires more strength but finishing is all about precision, patience, and a light touch. But what do you really need to know to finish your own drywall? Whether you’ve already started a project and need to know how to mud and tape drywall from start to finish or you’re just curious whether you want to try your hand at a patch job before calling in a professional, here’s what you need to know to get great results.
It All Starts with a Good Hang Job
There’s a stereotype in the drywall trade that finishing takes more skill than hanging and while that may or may not be true – we won’t weigh in on it here! – what’s certain is that the better the hang job, the easier it will be to mud and tape. As a result, take care to hang your sheetrock precisely, avoiding big gaps, rough spots, broken paper backing, and similar errors to ensure a smooth process finishing.
It Takes Time
You should expect to spend at least three days on finishing, almost no matter small the job is, because most finishing takes three coats of mud, and each coat needs to dry overnight before moving on to the next, so budget your time accordingly. You can’t rush the drying process and it’s crucial for good results. Similarly, pay attention and do a careful job when applying the mud, because this will save you a lot of time and mess down the road when it comes time to sand things smooth.
Step by step
With those tips in mind, it’s time to look at the step-by-step process to complete your finishing work.
- Gather your tools. You’ll need a pan or hawk to hold your compound while you work, a variety of drywall knives (a good starting set would consist of 6”, 8”, and 10” knives and perhaps a 12” knife as well), or trowel, an all-purpose joint compound, and drywall tape (either paper or mesh).
- Start by topping any holes or dimples. Before you actually start working on joints, check that there is nothing jutting out of your surface (like screws or nails). If there is, tighten screws or tap nails in until the head of the nail or screw is slightly below the surface of the sheetrock. Next, put some joint compound on your hawk or pan and use the 6” knife with a small amount of joint compound to fill in dimples and divots where the fasteners have sunk below the sheetrock surface. This will give you a perfectly smooth wall with no visible holes or bumps.
- Proceed with horizontal seams. If you’re using paper tape, get a 6” knife and begin applying joint compound over the horizontal seams between your drywall boards (this is called the “bedding coat”). Start by swiping some mud vertically over the seam, then lightly dragging the knife horizontally along the seam to spread the mud into a thin, consistent layer that gradually “feathers” out into the drywall surface. If you’re using fiberglass mesh tape, you can skip this step.
- Tape and mud over the horizontal seams. Apply your tape along the horizontal seams. If you’re using paper tape, make sure to do this step while the mud from step 3 is still wet. In either case, smooth the tape every 12”or so to make sure that it lies smooth against the wall and doesn’t have any air bubbles. Once the seams are taped, use the 8” knife to apply more mud over the tape, using a slight pressure and angle to ensure that the mud goes on smoothly over the tape and that the tape embeds into the mud. The 8” knife should feather the compound farther out onto the board (compared to the mud you put down in step 3). This is not only normal, but desirable: each step will use a progressively wider knife to taper the mud gradually into the wall, creating a smooth surface. If done correctly, by the end of the process, the transition will be invisible to the eye.
- Inside corners. Apply mud to each side of the corner with a 6” knife (for paper tape) then apply tape to the corner. When you apply the tape, fold it along the lengthwise seam before you apply it, not while you apply it. Next, mud over the tape as you did in step 4 with the horizontal seams. Start at the ceiling and smooth down towards the floor. Use a corner knife if you have one, as this tool will make it much easier to get an even spread on both sides of the corner as well as cutting the work time in half (since you do both sides of the corner at once). When you near the floor (within a foot or so), finish the corner by spreading compound up from the ground to meet the compound you’ve spread down. This ensures full coverage from floor to ceiling.
- Vertical seams. Do the vertical seams just like you did the horizontal seams and make sure not to overlap the vertical tape onto the horizontal tape, as this can build up unsightly bumps where the two pieces of tape meet.
- Outside corners. Use a corner bead to finish the outside corners. Start by applying a spray adhesive to the bead and stick it on to the corner. Next, use plenty of mud and a light pressure to get mud into the holes of the bead and helping it to adhere. Be sure to carefully feather the mud here to avoid a visible seam at the edge of the bead.
- Let it dry. Seriously, let the compound dry thoroughly (ideally 12 hours but at least overnight) before starting your second coat.
- Repeat the process with a bigger knife. Use an 8” knife for the second and put more joint compound over each of the seams and corners where you mudded the tape in yesterday. Be sure to feather the edges of the second coat so that it spreads a couple of inches past the first coat. Remember that your goal is to make the transition as gradual as possible so that it becomes invisible.
- Let it dry. Just like on the first day, it’s crucial to let your fresh coat of mud dry completely before starting any work. Let it dry overnight before coming back to work on it.
- Smooth any rough spots before you apply the finish coat. Run your drywall knife very gently over the surface of the mud you’ve applied. You’re not trying to apply any pressure, just identify any small bumps or imperfections in the (hopefully) smooth mud you’ve applied the last two days. Use a sander to treat any rough spots you find until everything is smooth.
- Final coat. For your finishing coat, dilute your joint compound with a very small amount of water (not more than one pint of water per 5-gallon bucket) to thin it out a bit. This will help it dry faster and allow the final coat to be thinner, lighter, and smoother. Apply your final coat with the 10” or 12” knife, feathering the edges out a couple of inches past the edges of the second coat.
- Finishing touches. Once the final coat is mostly dry, consider wiping it down with a damp sponge to smooth out any minor imperfections in the finish coat and to clean any dust left over from sanding. If there are rough spots that don’t come away with the sponge, use sandpaper (and a very light touch!) to remove them. We suggest using sponge back sandpaper. Be very careful here, as sanding too much will create uneven spots and can even expose the tape you spent so much time and effort to mud in.
That’s it – all you need to get started finishing drywall on your own. It may seem like a lot, but don’t get overwhelmed. It’s basically the same few steps done over and over with progressively larger knives to create a smooth transition. Just take your time and go carefully, and you’ll have a professional-looking result with a DIY price tag!