It's always best to do the job of patching drywall, or damaged plaster before installing your new kitchen or bathroom wall tile, Even if you don't need to remove an old wall covering.
It will make your wall tile installation not only look more professional but also more durable, and last much longer.
While preparing for your wall tile installation check to make sure your walls are straight, flat and plumb.
You should remove all wallpaper or any other wall covering you may have on your walls. Once removed, check for any structural or surface defects, such as loose drywall or damaged plaster.
It's fine to install a new wall tile installation over a painted wall, as long as the paints in good condition and not dirty, oily or glossy.
In some cases, You could simply install your bathroom or kitchen wall tiles right over the old tiles, but it's always best to remove the old wall tile installation before installing the new one.
You'll want to check the old substrate underneath and make sure there's no damage. Especially when installing a new wall installation to wet locations, such as a shower or tub surround.
Better to remove the old bathroom wall tile and the tile underlayment in these areas and replace it with a new Smooth, durable, watertight tile underlayment.
And Before installing bathroom wall tile to the dry areas of the bathroom check the condition of the wall structure. You can do this by pushing it in between the studs. And if you find any weak areas, drive drywall screws into the studs where drywall or plaster have come loose.
Also look for bows in the wall and crumbling damaged plaster, then fill in the depressions, remove loose materials and repair the holes.
*Fiberglass tape is made of fiberglass mesh to strengthen the joints between drywall sheets. But it's also excellent for repairing small holes.
*Vinyl Spackling compound comes pre-mixed making for an easy application. It dries fast and holds securely to the hole it's patching and it durable enough to withstand sanding and painting. It cleans up easily, and its specialty is in patching holes and covering nail or screw heads quickly and easily.
*Joint compound is also known as drywall compound or Mastic. It comes premixed and is commonly used with paper or fiber joint tape to seal the joints between drywall sheets to create a seamless base for interior walls.
*If your home was built after the 1950's, you're probably not familiar with walls made up of plaster or lath. You probably can relate more with sheetrock.
Before sheetrock came into existence in the 1950’s, interior walls and ceilings were made up of thin strips of wood, called lath. These wood strips were nailed horizontally across the vertical studs of the wall to form a foundation for supporting the plaster. Then several coats of plaster were layered on top of the lath and studs to create a solid wall.
*If you will be tiling over freshly installed sheet-rock that's been taped but not painted, or over repairs made with joint compound or spackling compound, you'll need to apply a coat of latex primer over the surface of only the joint compound or spackling compound.
This will prevent moisture in your tile mastic or thinset tile adhesives from dissolving the water soluble compound used on the sheet-rock. It also ensures proper adhesion.
Your first step in preparing for your new wall tile installation is to give your walls a little TLC. You will need a vinyl spackling compound, fiberglass mesh tape, and joint compound, to get the job done for repairing damaged plaster.
Simply fill any holes with vinyl spackling compound, Then cover the cracks with fiberglass mesh tape and cover with joint compound. It can be as simple as taping a joint between sheets of drywall.
If your plaster is severely pitted and crumbling, or severely cracked, you can remove it by beating against it with a hammer, to free it from the wood lath underneath. Then pry the lath off the studs with a crowbar.
But this method is a backbreaking job that requires wearing a respirator to protect your lungs, hanging plastic over the doors, so the thick clouds of dust don't fly all over the house, and you'll also be shoveling out hundreds of pounds of debris,
Thank goodness there's an easier way! You can simply install 1/4 inch sheet of sheetrock, right over the top of the old plaster.
Make sure you use sheet-rock screws that are long enough to go through the drywall, the damaged plaster, and the lath. The screws should also sink about 1 1/4 inches into the wall studs.
In the case, of patching drywall dings and dents, simply use a vinyl spackling compound. If you have holes in your drywall around the size of a quarter, apply a small strip of fiberglass mesh tape and joint compound. If you have bigger holes than this, follow the steps below.
Use a pencil and a framing square to draw a rectangle around the damaged area. Use a drywall saw, and cut along three sides. Score the face of the fourth side with a sharp utility knife. Snap the drywall, and cut the drywall paper on the back side.
Insert a scrap piece of wood into the hole, and make sure it stretches across two sides of the rectangle. Use drywall screws and a cordless drill, with a Phillips bit. To Fasten the piece of wood to the existing drywall, on each side. Be sure to countersink the screws.
Cut a replacement piece of new drywall, to fit your rectangle, reducing each dimension by 1/8 inch, to ensure that it will fit. Test your fit, and shave your edges if necessary, with a drywall rasp.
Once your fit is right, Use drywall screws to fasten your new rectangular sheet-rock, to the wood inside the hole. Don't use joint compound, as the tile adhesive you'll be using will dissolve the joint compound, and cause bonding problems.
If the sheetrock joints are tight, there's no need to fill them. If you do have gaps, it's better to use fiberglass mesh tape, and then apply one thin coat of the tile adhesive you will be using for installing your bathroom or kitchen wall tiles.
There are cases where patching drywall or damaged plaster may not be enough. Your walls may be too damaged to simply patch up the problem. If this is the case, you'll need to Install new drywall sheets
Once your done patching drywall and damaged plaster, you may want to take a peek at the different wall tile patterns you can use for laying your bathroom or kitchen wall tiles.