Tape Inside Drywall Corners
Category: Drywall ·
Difficulty: Intermediate ·
Time: 1.4h ·
Estimated cost: $19
Tools needed
- 6" taping knife
- 12" taping knife
- Inside-corner tool (optional)
- Mud pan
- Utility knife
- Sanding sponge (220 grit)
Materials needed
- Paper joint tape (250 ft) (1 roll)
- All-purpose joint compound (box/bucket) (1 box)
- Drywall primer/PVA (quart) (1 qt)
Execution steps
Pre-crease the tape
Paper tape has a center crease — fold it along the crease so it sits crisply into the 90°. Creased paper tape gives the sharpest beginner result.
Duration: 5 min
Lay the bed coat
Run a bed of mud down BOTH walls of the corner with the 6" knife.
Duration: 15 min
Set the tape
Press the folded tape into the corner, then pull the knife down ONE side per pass so you don't tear or wrinkle it. Squeeze out the excess, leaving mud under the tape.
Duration: 15 min
First finish side
Once dry, coat one side of the corner and feather it out. Doing one side at a time keeps the opposite side clean and crisp.
Duration: 15 min
Second finish side
Coat the other side and feather. A second thin coat per side beats one heavy coat that slumps.
Duration: 15 min
Sand and prime
Lightly sand both flats (not the very corner) with a 220 sponge, then prime before paint.
Duration: 20 min
Safety first
- Wear a dust mask when sanding.
- Use a stable ladder for ceiling corners and keep your hips inside the rails.
When to hire a pro
Long ceiling-to-wall runs or a level-5 finish over a whole room go faster and flatter for a taper — worth a pro for big, highly visible jobs.
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