Once it s ready for tiling there is no need to tape the joints.
Tiling on heavy gypsum plaster wall.
Holes or cracked plaster requires patching.
If you have a tiling job to do in your bathroom and the walls have been skimmed with plaster you have to follow a few guidelines when installing tile to make sure you do not have a failure resulting in all the tiles coming off the wall.
You should not tile over wallpaper glossy surfaces lead paint or plywood.
Firstly check the condition of the plaster skim it should be fully dried out and a light pink colour.
If you re not sure if you have lead paint test kits are available.
Expected load for tiling onto gypsum board should not exceed 32 kg m2.
It is needed for the adhesive to bond well.
The drying time is also affected by the thickness of the plaster layer.
Tiling over damp plaster causes the wall to fail because the plaster won t become strong if it can t dry out.
It is believed that the cement sand mortar dries at a speed of 1 cm in 7 days.
Tiling onto plaster backgrounds plaster is a weak material compared to brick and cement.
However tiling over tile can add quite a bit of thickness so make sure your wall can handle the weight.
Fresh plaster needs up to a month for the material to set in and fasten.
Preparation for tiling onto plasterboard plasterboard should be dry securely fixed and rigid with no protruding fixings with the face to receive decorative finishes exposed.
Make sure that gypsum board plaster board is strong enough to support the load from tiles and adhesive.
You may tile over existing tile painted or unpainted drywall plaster and textured walls.
Don t try to use the tile setting adhesive or drywall joint compound to patch plaster walls.
Laying of tiles on gypsum plaster is carried out in 7 14 days.
The adhesive and tile will block moisture from evaporating.
What this means for your installation is once it has been determined the gypsum board and its supporting structure have been properly designed constructed and installed to support a tile installation consult your setting material manufacturer to determine which of their adhesives or mortars and possibly primers are recommended to bond the tile to the painted gypsum substrate.
Fresh plaster whether applied as a patch or to the entire wall must dry completely before tile is applied.
When applying tile to a plastered surface it is important not to overload the weight of what the plaster will take before failure occurs plaster will support about 20kg m2 or about a 9mm thickness of ceramic tile.
Recommended thickness of the board is at least 12 5 mm.
Tiling onto plasterboard walls.