1. Tiling over a dusty substrate
The adhesive bonds to the dust, and the dust is attached to nothing. Sweep and vacuum before the first bucket. It takes minutes.
2. Guessing the water
4.8 to 5.2 litres per 20 kg bag is a specification, not a suggestion. Eyeballing it from a hose means over-watering, and over-watered adhesive is weak adhesive. Use a marked bucket.
3. Adding water to a stiffening batch
Re-tempering looks like it works — the mortar goes soft again. It has already started to set, and stirring water back in breaks the structure that was forming. Mix smaller batches instead. More on this in how to mix tile adhesive properly.
4. Combing more than you can tile
A bed that has skinned over will not grab. In summer heat the window is far shorter than people expect, so work about a square metre at a time and keep ahead of it.
5. Using the wrong trowel
Too small a notch is the leading cause of hollow tiles. Lift your first tile and look at the back — if you see bare stripes, go up a size. See the trowel size guide.
6. Placing tiles instead of pressing them
Resting a tile on the ridges leaves air channels between them. Press with a slight sliding movement so the ridges collapse sideways and close up.
7. Not back-buttering large tiles
Large format spans more of the substrate's imperfections, and combing alone rarely achieves full coverage. A thin skim on the back of the tile as well as the bed is the reliable fix.
8. Tiling tight with no movement joints
Every tiled surface expands and contracts, and outdoors it does so daily. With nowhere to move it relieves itself along a line you did not choose. Leave perimeter joints, and bay joints in larger areas.
9. Treating water resistance as waterproofing
A water-resistant adhesive is not a tanking membrane. In wet rooms and showers the membrane does the waterproofing and the tiles go over it — see tiling bathrooms and wet areas.
10. Grey adhesive under white grout
Squeeze-out you cannot fully clean out will discolour a light joint permanently. Match the adhesive colour to the grout and tile. Tile Bond 3100 comes in three:
Which to pick is covered in white or grey tile adhesive.
The pattern behind all ten
Every one of these saves a few minutes or a few rupees on the day and costs a return visit later. Substrate preparation, an accurate mix and full bed contact are where the job is actually won — the rest is tidying up.
Note: the figures here are typical values for Maira Tile Bond 3100 and are given as guidance. Real results vary with substrate, tile format, trowel size, temperature and site conditions. Confirm quantities and working times with Ali Traders before you order or start work.