No, you should not be able to see the drywall tape through your final coat of mud.
You shouldn't see the line of the tape when you are done. Either the tape wasn't embedded well enough into the seam, you are pulling off too much mud, or you are working non-tapered edges (which can also be fixed with more mud). Make sure you can't see the tape line when you are done skimming the wall.
If your drywall tape is showing, it usually means there was not enough joint compound (mud) applied to bury it, or the tape bubbled due to trapped air. To fix it, you need to either smooth out more mud over the seam or remove the failed section and re-tape it.
Avoiding Common Drywall Plastering and Taping Mistakes for a Professional Finish
Drywall tape should never be visible on a finished wall. After proper mudding, sanding, and painting, the seams and corners should be completely flat, seamless, and smooth to the touch.
When drywall tape shows through, it generally means the tape was applied over too little mud, the area was sanded too aggressively, or the joint compound shrank. To fix it, you must apply a wide layer of new joint compound to "feather" and hide the seam, then sand and prime.
For most standard drywall installations, you will need 3 coats of mud over your drywall tape to achieve a smooth, paint-ready surface.
Common Signs of a Bad Drywall Job
Visible seams or joint lines: You shouldn't be able to see where one drywall sheet ends and the next begins. If seams are showing through paint or primer, it likely means the taping and mudding were rushed or done unevenly. Uneven corners: Corners should be crisp and consistent.
Some drywall finishers add a small amount of dish soap (like Dawn) to drywall mud as a workability hack. They do this to act as a surfactant, which reduces the surface tension of the mud.
Two common mistakes made during drywalling are improper joint compound application (such as applying it too thickly or not feathering the edges), and failing to stagger the seams across different studs, which weakens the wall and increases the risk of cracking.
To hide drywall tape lines, you need to "feather" or widen the joint compound over the seams using a series of three progressively wider coats (6-inch, 10-inch, and 12-inch blades). The goal is to build a very wide, shallow taper that makes the joint completely flat and indistinguishable from the rest of the wall.
Humidity or Water Damage: Moisture is a common cause of drywall tape failure. Leaks, high humidity, or flooding can weaken the tape's adhesion and cause it to peel away. Building Settling: As buildings age, natural settling can cause movement in the walls, leading to cracks or separation of the tape.
To fix drywall tape showing through, you need to cut out any loose or bubbled tape using a utility knife, apply a fresh layer of joint compound, and feather out the edges. Sand the area smoothly, prime, and repaint.
Apply a layer of drywall mud to the seam first, then press drywall tape into the wet compound. Use a putty knife to smooth the tape, remove air bubbles and ensure strong adhesion before applying additional coats of mud.
Options And When to Skip Skim Coating
If your painted walls are mostly smooth with only minor flaws, you may not need a full skim coat.
One of the most immediate and obvious consequences of forgoing drywall tape is the appearance of visible seams and cracks. You'll have uneven, unsightly lines running across your wall that will make even the most forgiving paint job look terrible. Drywall is not a fan of moisture.
Dry heat and air flow are the best bet.
An orbital sander is an option for a large drywall project. This tool is lightweight and can perform the task in less time, but as a power tool it must be used carefully to avoid damaging the drywall surface. Use fine grit sandpaper, between 150 and 180 grit, to achieve the desired results.
Apply Second Coat of Mud
Taping and mudding the joints and corners is just one part of knowing how to mud drywall. The next step is to apply a second coat of compound to these same areas. No paper drywall tape is needed for this step. Apply a thin layer of mud with a 10-inch drywall knife.
Over time, breathing the dust from drywall joint compounds may cause persistent throat and airway irritation, coughing, phlegm production, and breathing difficulties similar to asthma.
8 Common Drywall Repair Mistakes and How to Avoid Them
Applying too little mud can result in a weak, fracture-prone joint. Additionally, it could make it challenging to get a smooth finish. Apply enough mud to thoroughly cover the joint to prevent this error. Spread the mud evenly over the joint using a taping knife, ensuring you fill any gaps or holes.
Yes, a fan will help standard drywall mud dry faster by circulating air and speeding up moisture evaporation. However, it is important to understand the type of mud you are using, as fans work best on standard premixed compounds but won't speed up the curing time of chemical-setting compounds.