Grouting ceramic wall tiles
Grouting ceramic wall tiles should be carried out over the whole tiled area only when all the tiles have been fixed and allowed to firm up (at least 24 hours after the last tile was fixed).
Start by making sure that all tile faces and joints are clean - especially that there is no tile adhesive present on the surfaces or edges of the joints.
Make sure that you have the correct type of grout for where you are using it, i.e. waterproof where necessary.
Grout can be purchase either as premixed or as powder for mixing with water.
If necessary, mix the grout powder as per the instructions to a smooth lump free consistency; if the grout is too runny, the grout will run out of the joints, while if it is too stiff, it will be impossible to work the grout into the joints.
Work in areas of about one square metre (or sq yard) at a time, otherwise you may find that the grout becomes unworkable before you finish the filling and sponging. But having said that, keep moving onto new areas on a wall so that the whole wall is completed in one session otherwise visible joints in the grout may appear. If you have to stop grouting part way through, clean the joints back so that there is a definite finish line and taper the grout back so that when the grouting is restarted, the new grouting will go over the taper.
With a squeegee or grout float (a float with a flexible edge) held at about 45 degrees to the tile face, pull the grout across the tiles and into the joints from both directions - as the joints form a grid, it will be necessary to keep turning the squeegee through 90° to fill both the vertical and horizontal joints. Use a finger to fill any joints where you cannot get the squeegee.
When all the joints have been completely filled, hold the squeegee about 90 degrees to the tile face and pull it diagonally across the joints to remove any excess grout - this should keep the grout level with the tile face.
Tiles with a square edge need to have the grout finished flush with the tiled surface whereas tiles with a radius edge should have the grout finished to the bottom of the radius.
After the grout has hardened for about 10 minutes, clean off the surplus grout from the tile surface by lightly wiping a clean, damp sponge across them - keep rinsing the sponge so that it remains clean.
Depending on the required finish:
- For a level joint finish, repeat the sponging after another five minutes to level the joints.
- For a concave joint finish, smooth the joints using a round finishing tool (or the end of a length of wooden doweling), remove the grout material which comes out of the joints.
Repeat the sponging with a almost dry sponge and, if the joints are concave, run the finishing tool over the joints again.
After 24 hours, wash down the tiles once or twice to remove any grout residue from the tile surface. When the tiles have dried, polish them using a soft dry cloth to remove any remaining film of grout on the tile faces.