I have plaster walls in my house and they have cracks. I have tried to fix the cracks with paper tape and nylon wall tape, but the cracks keep coming through the mudding. How can I fix them permanently?
Cracks in plaster walls are pretty typical. When plaster's first installed, it's troweled through wood sticks called plaster lath. It spreads behind the lath, and that's how it sticks to the wall.
If it cracks - and it often does, as the structure settles - you can do a few things to fix the plaster. Plaster washers are one solution. A plaster washer looks like a fender washer with holes in it. Put a couple of them on both sides of the crack. The plaster washer will support the loose plaster wall and hold it up. From there, apply nylon tape and replaster. This addresses both the structural and cosmetic issues. Nonetheless, there's a good chance cracks will keep appearing It's just how things go as your house continues to move and settle.