A bathroom that survives a Bangalore monsoon

A bathroom that fails does not fail in the bathroom. It fails as a stain on the bedroom wall behind it, and by then the fix involves breaking tiles. Almost all of it is decided before the first tile goes on.

Waterproofing is the whole job

Get the membrane right and the rest is decoration. The rules are unglamorous:

• Take the waterproofing up the wall, not just across the floor — at least a foot everywhere, and full height in the shower.
• Treat the junctions: floor to wall, around the drain, around every pipe penetration. That is where water gets through, not through the middle of a slab.
• Insist on a flood test before tiling. Plug the drain, fill the floor, leave it a day, check the ceiling below. One day now against a fortnight of demolition later.

Slope and drainage

Water has to leave faster than it arrives. A gentle, consistent fall to the drain — and the drain positioned where the water actually goes, which is usually not the geometric centre of the room. Standing water is what turns grout black.

If you can pour a mug of water on the floor and it sits there, the bathroom is already failing. It just hasn't told you yet.

Ventilation is not optional here

In a Bengaluru monsoon the air is already saturated; a bathroom with no extract fan simply stays wet. An exhaust vented outside — not into the false ceiling — run on the same switch as the light, with a timer if you can. Mould needs damp and stillness. Take away the stillness.

Choices that age well

1. Larger tiles, fewer joints. Grout is the weak point; less of it is less to maintain. Epoxy grout in the shower is worth the extra.
2. Matte or textured floor tiles. Polished stone plus wet feet is how people fall.
3. Stainless or brass fittings, not plated zinc. Plating blisters in humidity and cannot be repaired.
4. Wall-hung vanity. The floor dries, and you can clean under it.
5. Marine-ply or WPC vanity carcass. Regular MDF swells at the base, quietly, until the door stops closing.

None of this is visible in a photograph of a finished bathroom. All of it is the difference between one that looks the same in five years and one that doesn't.