How to Work with Fiberglass Tape

Fiberglass tape is ideal for patching holes in drywall or as a paper tape substitute. Follow these steps for the best results.

covering tape with thinset

Fiberglass mesh tape is easier to use than paper tape. Paper tape needs to be pressed into a layer of compound and the excess compound removed. The trick is that you must remove surplus compound without wrinkling the tape or removing so much that the tape buckles because you've created dry spots. Faced with all of those paper tape challenges, you'll probably agree that fiberglass tape is worth its extra cost.

When you buy fiberglass tape, ensure that the package indicates it's self-adhesive. While the nonadhesive version is scarce, getting a roll could be an unpleasant surprise.

Be sure you keep a sharp utility knife blade available to cut fiberglass tape. A dull blade will merely skip over the fabric or snag the threads. If you're tackling a big project, consider getting a tape dispenser. It's a speedy helper for both flat seams and inside corners. Below, we show you how to effectively use fiberglass tape.

What You'll Need

Equipment / Tools

  • Mud pan
  • Drywall knife
  • Utility knife

Materials

  • Drywall compound
  • Fiberglass mesh tape

Instructions

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    Fill Gaps

    If you have gaps of ¼-inch or wider, you'll need to fill them before applying tape. Although you could utilize all-purpose ready-mixed compound for this step, the thick application can take a long time to dry, delaying your project. For that reason, a setting-type compound with a short set time is your best choice.

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    Repair Walls

    Repairing blowouts, miscuts, and other damage is the next step. In this case, careless handling during installation resulted in torn paper that reveals the gypsum core. Cover the damaged area with strips of fiberglass tape applied edge to edge. Cover the tape with a thin layer of compound. Again, a setting-type compound is a good choice for this step, though you can also choose other types of drywall finishes.

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    Apply Tape

    Applying fiberglass tape is extremely easy. Center its width over the drywall seam, and press down firmly. Wearing a glove on your press-down hand protects your fingertips from abrasion. Cut the tape with a sharp utility knife. Apply the tape into tapered seams first, ending each wall with a cut at inside or outside corners.

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    Seal Edges

    Use a 6-inch taping knife to shove fiberglass tape into inside corners, then press down both sides firmly. For maximum joint strength, keep the mesh centered in the corner. Run this layer of tape over the pieces that you applied to the tapered seams.

  5. Mud Over Tape Immediately

    Fiberglass tape doesn't have an aggressive adhesive, so it's not wise to trust it any longer than necessary, especially on ceilings. As soon as you finish taping a room, proceed immediately to the first coat of compound to embed the tape.

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Tip: Fast-Draw Taping

For big jobs, consider a tape gun specifically made for applying fiberglass drywall tape. A built-in cutter neatly snips the tape so you don't have to carry a utility knife. The tool firmly presses the tape into place for additional holding strength.

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How to Store Fiberglass Tape

Extend the life of fiberglass drywall tape by storing it in a plastic bag. Airtight storage helps keeps the adhesive fresh and shields the tape from drywall dust, another culprit that reduces tackiness.

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