Finishing
Paper vs mesh tape: strength, speed and where each belongs
Mesh is quicker to put on and paper is stronger once it is on. The right answer depends on the joint, and on the compound you bed it in.
Two tapes
Paper tape is a strip of strong paper about 2 in wide with a crease down the middle. It is bedded in a layer of compound, pressed flat with a knife to squeeze out the excess, and covered. The crease lets it fold cleanly into inside corners. Paper does not stretch, so a paper-taped joint resists cracking well.
Fibreglass mesh tape is an open-weave strip with an adhesive back. It sticks to the board before any compound goes on, so a whole room can be taped in minutes, and compound pushes through the weave. Mesh stretches a little under load, which is why a mesh joint finished with ordinary ready-mix can crack along its length.
Compared
| Paper | Mesh | |
|---|---|---|
| Strength across the joint | Higher; does not stretch | Lower; stretches slightly |
| Speed | Bedded in a coat of compound | Sticks on dry; fast |
| Compound | Any; ready-mix or setting | Setting-type compound for the first coat |
| Inside corners | Folds cleanly on its crease | Hard to fold neatly |
| Bubbles | Possible if under-bedded | Rare |
| Roll | 250 or 500 ft | 150 or 300 ft |
| Typical use | Flat joints, butt joints, inside corners | Flat joints with setting compound, repairs, patches |
Mesh needs setting compound for its first coat because setting compound is stronger and does not shrink as it dries, which compensates for the stretch in the mesh. Ready-mix over mesh is the most common cause of hairline cracks along a joint. The mixing ratios are on the setting compound calculator, and the guide to joint compound types explains the two families.
How much tape
Each sheet brings about one long edge and one end of joint, because every joint is shared by two sheets. A 4 × 8 sheet brings about 12 ft, a 4 × 12 about 16 ft. Add the inside corners: every wall-to-wall corner the height of the room, and the full perimeter where the walls meet the ceiling.
40 sheets of 4 × 8 with 160 ft of inside corners
- Flat joints: 40 × 12 = 480 ft
- Tape: (480 + 160) × 1.1 = 704 ft
- In paper: 2 rolls of 500 ft
- Mesh on the flats, paper in the corners: 2 rolls of 300 ft mesh for 528 ft of flats, and 1 roll of 250 ft paper for 176 ft of corners
The drywall tape calculator counts both ways.
Where each belongs
- Inside corners: paper, folded on its crease. Metal-reinforced or plastic corner tape for corners that are out of square or meet at odd angles.
- Flat tapered joints: either. Paper with ready-mix or setting compound, or mesh with setting compound.
- Butt joints: paper is the safer choice, because butt joints move most and show most.
- Patches and repairs: mesh, with setting compound, is quick and strong enough for small areas; the guide to drywall repairs covers it.
- Cement board under tile: alkali-resistant mesh with setting compound or thinset. Ordinary mesh degrades in cement.
- Fire-rated assemblies: what the listing names. Most require the face-layer joints taped and covered; use the tape and compound the listing allows.
Bedding paper tape well
Most paper-tape failures are bubbles and loose edges where the tape was not fully bedded. Put a generous layer of compound along the joint, press the tape in, and wipe down firmly with a 6 in knife from the middle out, leaving a thin film under the tape. Wet the tape first if the compound is stiff. Too little compound under the tape, or compound that skinned over before the tape went on, leaves it loose.
Outside corners take bead, not tape
Outside corners are protected with corner bead: a metal, vinyl or paper-faced angle fixed over the corner and buried in compound. Metal bead is nailed or crimped; vinyl and paper-faced bead are set in compound or sprayed with adhesive. Paper-faced bead resists cracking best; vinyl and paper-faced suit damp rooms, where metal can rust.
A room with four 8 ft outside corners and two returned 3 × 5 ft windows
- Corners: 4 pieces of 8 ft bead, one per corner
- Window returns: 2 × 13 ft = 26 ft, 4 more pieces with waste
- 8 pieces of 8 ft bead, about 155 nails or a crimper
The corner bead calculator counts bead by corner and by run. Buy bead long enough to cover each corner in one piece; a splice is where corners crack.
Compound for the joints
The tape sets the joints; the compound finishes them. A Level 4 finish takes about 9.4 gallons of ready-mix per 1,000 sq ft of board, tape coat included, which the joint compound calculator turns into pails. How many coats go over the tape depends on the finish level, explained in the guide to levels of drywall finish.
Common mistakes
- Mesh with ready-mix. Cracks along the joint.
- Dry paper bedded in stiff mud. Bubbles; wet the tape or thin the compound.
- Mesh in inside corners. It will not fold; use paper.
- Splicing corner bead on a 9 ft corner. Buy 10 ft pieces.
- Taping over gaps wider than 1/4 in. Fill them with setting compound first.