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Paper vs. Mesh Tape: Why Your Inside Corners Are Cracking

Mesh tape is self-sticking and easier to embed in flat joints, but it has no strength across the joint. When the building settles or the framing moves even a little, mesh tape cracks right down the middle of the joint. Paper tape, especially pre-creased paper tape for inside corners, has tensile strength that bridges the joint and holds it together through minor movement.

The rule is simple: paper tape for inside corners, mesh for flat joints if you prefer it. Many pros use paper tape for everything because it is stronger and cheaper. If your inside corners are cracking, switch to paper tape and use a corner trowel to embed it properly. The corner trowel holds the crease in the right place while you embed the tape in the mud.

The “Flashing” Nightmare: Why You Must Prime Before Painting

Flashing is when the joints show through the paint as shiny or dull spots under certain lighting. It happens because the joint compound and the paper face of the drywall absorb paint at different rates. If you paint directly over unprimed drywall, the joints absorb more paint and look different from the rest of the wall.

The fix is a coat of PVA drywall primer before the topcoat. PVA primer seals the drywall and the joints so they absorb paint at the same rate. If you are using flat or eggshell paint, you might get away without primer, but if you are using satin, semi-gloss, or gloss paint, the flashing will show. Always prime. It is cheap insurance against a repaint job.

Why You Should Always Hang Ceilings Before Walls

The ceiling sheets need to rest on something solid. If you hang the walls first, the ceiling sheets rest on the wall edges, which creates a weak joint that can crack when the building settles. If you hang the ceilings first, the wall sheets push up tight against the ceiling sheets, creating a tight, supported joint that holds together.

The trick is to use a drywall lift for the ceilings if you are working alone. A drywall lift holds the sheet up while you screw it in, so you do not have to hold it up with one hand and screw with the other. If you do not have a lift, rent one for the day. It saves your back and makes the ceiling job go much faster.

How to Avoid “Popping” Screws Months After the Job is Done

Screw pops happen when the screw head breaks through the paper face of the drywall after the job is done. It happens because the screw was not driven deep enough, or the framing moved and pulled the screw out. The fix is to drive the screw so the head is just below the surface of the paper, creating a small dimple but not breaking the paper.

If a screw pops after the job is done, drive another screw an inch or two away from the popped screw, then mud over both screw heads. Do not try to push the popped screw back in; it will just pop again. The new screw holds the drywall tight to the framing, and the mud hides both screw heads.

All-Purpose vs. Topping Compound: When to Use Which

All-purpose compound is the workhorse: it sticks well, sands well, and works for all three coats if you are doing a Level 4 finish. Topping compound is lighter and sands easier, but it does not stick as well as all-purpose. Many pros use all-purpose for the taping coat and topping for the fill and top coats.

If you are doing a Level 5 finish with a skim coat, use topping compound or a lightweight all-purpose for the skim coat because it sands easier. All-purpose is harder to sand smooth, and a skim coat needs to be feathered out to nothing. For a Level 4 finish, all-purpose for all three coats is fine and cheaper.