The three types
| Type | Rate | Stain resistance | Where |
|---|---|---|---|
| Sanded cement grout | ₹18–30 / kg | Poor | Dry floors, wide joints |
| Unsanded cement grout | ₹22–35 / kg | Poor | Narrow joints, wall tile |
| Polymer-modified cement | ₹60–140 / kg | Moderate | General residential, better colour hold |
| Epoxy grout | ₹450–950 / kg | Excellent | Kitchens, bathrooms, balconies |
Joint width is a technical decision
Rectified tiles allow 2 mm; non-rectified need 3 mm to absorb the size variation between pieces. Large format slabs need at least 2 mm regardless — a butt joint has nowhere to accommodate thermal movement and the tiles will lip or chip at the edges. Anyone who offers a “zero joint” floor is either using a rectified tile at 1.5 mm or setting up a failure.
Colour: the decision that changes the room
Grout matched to the tile makes a floor read as one surface; a contrasting grout draws the grid and makes a room look busier and smaller. On a large-format floor, match. On a subway-tile backsplash where the grid is the point, contrast. The practical caution is that mid-grey hides Mumbai dust and cooking film far better than white or charcoal, both of which show everything.
Two application details separate a good grout job from a poor one. The joints must be raked clean of adhesive to at least two-thirds of the tile depth before grouting, and the haze must come off within the window the manufacturer states. Dried haze on a matte tile is close to permanent.
Why cement grout fails
It is porous. Water carries dirt in, soap and oil stain it, and in a shower it grows mould in the joints within a year. It can be sealed at ₹8–15 per sq ft and resealed annually, or replaced with epoxy in wet areas from the start. Re-grouting an existing bathroom — raking out and refilling with epoxy — costs ₹90–180 per sq ft and is one of the highest-value small renovations available. See vitrified tiles and bathroom renovation costs.
Frequently asked questions
How long does grout last?+
Cement grout in a shower begins to discolour within a year and typically needs raking out and replacing at five to eight years. Epoxy grout in the same position lasts the life of the tiling.
Can grout be changed without removing tiles?+
Yes. The old grout is raked out with a grout saw or an oscillating tool and the joints refilled. It is dusty, slow work at ₹90–180 per sq ft, and it makes an old bathroom look new without touching the tiles.
What grout colour should I choose?+
A mid tone close to the tile for large floors, and a deliberate contrast only where the grid is part of the design. Avoid pure white on a floor and charcoal on a kitchen wall — both show their opposite of dirt.
Is grout waterproof?+
Cement grout is not; epoxy grout largely is. Neither is a waterproofing system. The membrane behind and below the tile does that job, and no grout compensates for its absence.