How to Tape Drywall Joints


Complete your drywall installation by taping the joints together

How to Tape Drywall Joints

After putting up drywall, you must connect all the pieces into one solid wall before priming and painting. This guide will walk you step-by-step through that process.

Safety: Wear appropriate respiratory protection when sanding drywall, and apply plastic or canvas drop cloths to prevent the sanding dust from damaging nearby furniture or spreading beyond your immediate work area.


Fill the troughs along the sheet edges
Fill troughs along sheet edges - Tape Drywall Joints

• The long edge of each drywall sheet is beveled, purposely made thinner than the rest of the sheet. This creates a trough when the edges are put together. Seams of butt joints with beveled edges get a strip of paper reinforcing tape and three coats of joint compound. Each coat is slightly wider than the previous coat, and the final coat is 24 inches wide.
• Build up about an inch of joint compound on a 6-inch knife, and fill the trough with compound.

Apply tape
Apply tape - How Tape Drywall Joints

Put paper drywall tape in the compound in the trough, pushing it in every foot or so to hold it in place.

Smooth the tape
Smooth tape - How Tape Drywall Joints

• Pull the putty knife along the tape, embedding it in the mud.
• If you start in the corner and work toward the middle of the room, the tape will pull loose. Start in the middle and work towards the corners, at least until you have the ends embedded in the compound.

Apply a second coat
Apply second coat - How Tape Drywall Joints

• Let the compound dry overnight and apply a second coat of compound with a 10-inch knife.
• Let the second layer dry overnight.

Apply a third coat
Apply third coat - How Tape Drywall Joints

• Thin the joint compound with water to the consistency of mayonnaise before you apply the third coat.
• The thinner compound goes on more easily, fills irregularities and is less likely to leave small pinholes as you spread it.
• Apply the compound with a 12-inch knife and let dry overnight.

Sand everything
Sand everything - How Tape Drywall Joints

• Once completely dry, sand the surface smooth using a pole sander and 120-grit paper.
• Start by folding the paper around the ends of the pads and tightening the wing nuts on the back to clamp it in place. Run the pole over the joints until you get a smooth surface with no steps between the edge of the compound and the drywall and with no ridges or pinholes elsewhere in the compound.